feat: auto-track fields on context for zero-arg ValidateAll/ResetFields

Fields created via Context.Field are now tracked on the page context,
so ValidateAll() and ResetFields() with no arguments operate on all
fields by default. Explicit field args still work for selective use.

Also switches MinLen/MaxLen to utf8.RuneCountInString for correct
unicode handling and replaces fmt.Errorf with errors.New where
format strings are unnecessary.

README.md

@@ -1,30 +1,33 @@
-# ⚡Via
+# Via
+
 Real-time engine for building reactive web applications in pure Go.
 
-
 ## Why Via?
-Somewhere along the way, the web became tangled in layers of JavaScript, build chains, and frameworks stacked on frameworks.
 
-Via takes a radical stance:
+The web became tangled in layers of JavaScript, build chains, and frameworks stacked on frameworks. Via takes a different path.
 
-- No templates.
-- No JavaScript.
-- No transpilation.
-- No hydration.
-- No front-end fatigue.
-- Single SSE stream.
-- Full reactivity.
-- Built-in Brotli compression.
-- Pure Go.
+**Philosophy**
+- No templates. No JavaScript. No transpilation. No hydration.
+- Views are pure Go functions. HTML is composed with a type-safe DSL.
+- A single SSE stream carries all reactivity — no WebSocket juggling, no polling.
 
+**Batteries included**
+- Automatic CSRF protection on every action call
+- Token-bucket rate limiting (global defaults + per-action overrides)
+- Cookie-based sessions backed by SQLite
+- Pub/sub messaging with an embedded NATS backend
+- Structured logging via zerolog
+- Graceful shutdown with context draining
+- Brotli compression out of the box
 
 ## Example
+
 ```go
 package main
 
 import (
-	"github.com/go-via/via"
-	"github.com/go-via/via/h"
+	"github.com/ryanhamamura/via"
+	"github.com/ryanhamamura/via/h"
 )
 
 type Counter struct{ Count int }
@@ -57,25 +60,43 @@ func main() {
 }
 ```
 
+## What's built in
 
-## 🚧 Experimental
-<s>Via is still a newborn.</s> Via is taking its first steps!
-- Version `0.1.0` released.
-- Expect a little less chaos.
+- **Reactive views + signals** — bind state to the DOM; changes push over SSE automatically
+- **Components** — self-contained subcontexts with their own data, actions, and signals
+- **Sessions** — cookie-based, backed by SQLite via `scs`
+- **Pub/sub** — embedded NATS server with JetStream; generic `Publish[T]` / `Subscribe[T]` helpers
+- **CSRF protection** — automatic token generation and validation on every action
+- **Rate limiting** — token-bucket algorithm, configurable globally and per-action
+- **Event handling** — `OnClick`, `OnChange`, `OnSubmit`, `OnInput`, `OnFocus`, `OnBlur`, `OnMouseEnter`, `OnMouseLeave`, `OnScroll`, `OnDblClick`, `OnKeyDown`, and `OnKeyDownMap` for multi-key bindings
+- **Timed routines** — `OnInterval` with start/stop/update controls, tied to context lifecycle
+- **Redirects** — `Redirect`, `ReplaceURL`, and format-string variants
+- **Plugin system** — `func(v *V)` hooks for integrating CSS/JS libraries
+- **Structured logging** — zerolog with configurable levels; console output in dev, JSON in production
+- **Graceful shutdown** — listens for SIGINT/SIGTERM, drains contexts, closes pub/sub
+- **Context lifecycle** — background reaper cleans up disconnected contexts; configurable TTL
+- **HTML DSL** — the `h` package provides type-safe Go-native HTML composition
+
+## Examples
+
+The `internal/examples/` directory contains 14 runnable examples:
+
+`chatroom` · `counter` · `countercomp` · `greeter` · `keyboard` · `livereload` · `nats-chatroom` · `pathparams` · `picocss` · `plugins` · `pubsub-crud` · `realtimechart` · `session` · `shakespeare`
+
+## Experimental
+
+Via is maturing — sessions, CSRF, rate limiting, pub/sub, and graceful shutdown are in place — but the API is still evolving. Expect breaking changes before `v1`.
 
 ## Contributing
+
 - Via is intentionally minimal and opinionated — and so is contributing.
-- If you love Go, simplicity, and meaningful abstractions — Come along for the ride!
-- Fork, branch, build, tinker with things, submit a pull request.
+- Fork, branch, build, tinker, submit a pull request.
 - Keep every line purposeful.
 - Share feedback: open an issue or start a discussion.
 
-
 ## Credits
 
-Via builds upon the work of these amazing projects:
+Via builds upon the work of these projects:
 
-- 🚀 [Datastar](https://data-star.dev) - The hypermedia powerhouse at the core of Via. It powers browser reactivity through Signals and enables real-time HTML/Signal patches over an always-on SSE event stream.
-- 🧩 [Gomponents](https://maragu.dev/gomponents) - The awesome project that gifts Via with Go-native HTML composition superpowers through the `via/h` package.
-
-> Thank you for building something that doesn’t just function — it inspires. 🫶
+- [Datastar](https://data-star.dev) — the hypermedia framework powering browser reactivity through signals and real-time HTML patches over SSE.
+- [Gomponents](https://maragu.dev/gomponents) — Go-native HTML composition that powers the `via/h` package.

actiontrigger.go

@@ -107,6 +107,54 @@ func (a *actionTrigger) OnChange(options ...ActionTriggerOption) h.H {
 	return h.Data("on:change__debounce.200ms", buildOnExpr(actionURL(a.id), &opts))
 }
 
+// OnSubmit returns a via.h DOM attribute that triggers on form submit.
+func (a *actionTrigger) OnSubmit(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:submit", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnInput returns a via.h DOM attribute that triggers on input (without debounce).
+func (a *actionTrigger) OnInput(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:input", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnFocus returns a via.h DOM attribute that triggers when the element gains focus.
+func (a *actionTrigger) OnFocus(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:focus", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnBlur returns a via.h DOM attribute that triggers when the element loses focus.
+func (a *actionTrigger) OnBlur(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:blur", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnMouseEnter returns a via.h DOM attribute that triggers when the mouse enters the element.
+func (a *actionTrigger) OnMouseEnter(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:mouseenter", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnMouseLeave returns a via.h DOM attribute that triggers when the mouse leaves the element.
+func (a *actionTrigger) OnMouseLeave(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:mouseleave", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnScroll returns a via.h DOM attribute that triggers on scroll.
+func (a *actionTrigger) OnScroll(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:scroll", buildOnExpr(actionURL(a.id), &opts))
+}
+
+// OnDblClick returns a via.h DOM attribute that triggers on double click.
+func (a *actionTrigger) OnDblClick(options ...ActionTriggerOption) h.H {
+	opts := applyOptions(options...)
+	return h.Data("on:dblclick", buildOnExpr(actionURL(a.id), &opts))
+}
+
 // OnKeyDown returns a via.h DOM attribute that triggers when a key is pressed.
 // key: optional, see https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key
 // Example: OnKeyDown("Enter")

configuration.go

@@ -1,6 +1,8 @@
 package via
 
 import (
+	"time"
+
 	"github.com/alexedwards/scs/v2"
 	"github.com/rs/zerolog"
 )
@@ -54,4 +56,14 @@ type Options struct {
 	// PubSub enables publish/subscribe messaging. Use vianats.New() for an
 	// embedded NATS backend, or supply any PubSub implementation.
 	PubSub PubSub
+
+	// ContextTTL is the maximum time a context may exist without an SSE
+	// connection before the background reaper disposes it.
+	// Default: 30s. Negative value disables the reaper.
+	ContextTTL time.Duration
+
+	// ActionRateLimit configures the default token-bucket rate limiter for
+	// action endpoints. Zero values use built-in defaults (10 req/s, burst 20).
+	// Set Rate to -1 to disable rate limiting entirely.
+	ActionRateLimit RateLimitConfig
 }

context.go

@@ -5,12 +5,13 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"maps"
 	"reflect"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/ryanhamamura/via/h"
+	"golang.org/x/time/rate"
 )
 
 // Context is the living bridge between Go and the browser.
@@ -19,20 +20,24 @@ import (
 type Context struct {
 	id                string
 	route             string
+	csrfToken         string
 	app               *V
 	view              func() h.H
 	routeParams       map[string]string
-	componentRegistry map[string]*Context
 	parentPageCtx *Context
 	patchChan         chan patch
-	actionRegistry    map[string]func()
+	actionLimiter     *rate.Limiter
+	actionRegistry    map[string]actionEntry
 	signals           *sync.Map
 	mu                sync.RWMutex
 	ctxDisposedChan   chan struct{}
 	reqCtx            context.Context
+	fields            []*Field
 	subscriptions     []Subscription
 	subsMu            sync.Mutex
 	disposeOnce       sync.Once
+	createdAt         time.Time
+	sseConnected      atomic.Bool
 }
 
 // View defines the UI rendered by this context.
@@ -75,7 +80,6 @@ func (c *Context) Component(initCtx func(c *Context)) func() h.H {
 		compCtx.parentPageCtx = c
 	}
 	initCtx(compCtx)
-	c.componentRegistry[id] = compCtx
 	return compCtx.view
 }
 
@@ -100,26 +104,31 @@ func (c *Context) isComponent() bool {
 //		 	 	h.Button(h.Text("Increment n"), increment.OnClick()),
 //		 )
 //	})
-func (c *Context) Action(f func()) *actionTrigger {
+func (c *Context) Action(f func(), opts ...ActionOption) *actionTrigger {
 	id := genRandID()
 	if f == nil {
 		c.app.logErr(c, "failed to bind action '%s' to context: nil func", id)
 		return nil
 	}
 
+	entry := actionEntry{fn: f}
+	for _, opt := range opts {
+		opt(&entry)
+	}
+
 	if c.isComponent() {
-		c.parentPageCtx.actionRegistry[id] = f
+		c.parentPageCtx.actionRegistry[id] = entry
 	} else {
-		c.actionRegistry[id] = f
+		c.actionRegistry[id] = entry
 	}
 	return &actionTrigger{id}
 }
 
-func (c *Context) getActionFn(id string) (func(), error) {
-	if f, ok := c.actionRegistry[id]; ok {
-		return f, nil
+func (c *Context) getAction(id string) (actionEntry, error) {
+	if e, ok := c.actionRegistry[id]; ok {
+		return e, nil
 	}
-	return nil, fmt.Errorf("action '%s' not found", id)
+	return actionEntry{}, fmt.Errorf("action '%s' not found", id)
 }
 
 // OnInterval starts a go routine that sets a time.Ticker with the given duration and executes
@@ -197,14 +206,14 @@ func (c *Context) injectSignals(sigs map[string]any) {
 	defer c.mu.Unlock()
 
 	for sigID, val := range sigs {
-		if _, ok := c.signals.Load(sigID); !ok {
+		item, ok := c.signals.Load(sigID)
+		if !ok {
 			c.signals.Store(sigID, &signal{
 				id:  sigID,
 				val: val,
 			})
 			continue
 		}
-		item, _ := c.signals.Load(sigID)
 		if sig, ok := item.(*signal); ok {
 			sig.val = val
 			sig.changed = false
@@ -255,7 +264,7 @@ func (c *Context) sendPatch(p patch) {
 // Sync pushes the current view state and signal changes to the browser immediately
 // over the live SSE event stream.
 func (c *Context) Sync() {
-	elemsPatch := bytes.NewBuffer(make([]byte, 0))
+	elemsPatch := new(bytes.Buffer)
 	if err := c.view().Render(elemsPatch); err != nil {
 		c.app.logErr(c, "sync view failed: %v", err)
 		return
@@ -320,6 +329,15 @@ func (c *Context) ExecScript(s string) {
 	c.sendPatch(patch{patchTypeScript, s})
 }
 
+// RedirectView sets a view that redirects the browser to the given URL.
+// Use this in middleware to abort the chain and redirect in one step.
+func (c *Context) RedirectView(url string) {
+	c.View(func() h.H {
+		c.Redirect(url)
+		return h.Div()
+	})
+}
+
 // Redirect navigates the browser to the given URL.
 // This triggers a full page navigation - the current context will be disposed
 // and a new context created at the destination URL.
@@ -375,12 +393,9 @@ func (c *Context) injectRouteParams(params map[string]string) {
 	if params == nil {
 		return
 	}
-	m := make(map[string]string)
 	c.mu.Lock()
 	defer c.mu.Unlock()
-	maps.Copy(m, params)
-	c.routeParams = m
-
+	c.routeParams = params
 }
 
 // GetPathParam retrieves the value from the page request URL for the given parameter name
@@ -466,6 +481,50 @@ func (c *Context) unsubscribeAll() {
 	}
 }
 
+// Field creates a signal with validation rules attached.
+// The initial value seeds both the signal and the reset target.
+// The field is tracked on the context so ValidateAll/ResetFields
+// can operate on all fields by default.
+func (c *Context) Field(initial any, rules ...Rule) *Field {
+	f := &Field{
+		signal:     c.Signal(initial),
+		rules:      rules,
+		initialVal: initial,
+	}
+	target := c
+	if c.isComponent() {
+		target = c.parentPageCtx
+	}
+	target.fields = append(target.fields, f)
+	return f
+}
+
+// ValidateAll runs Validate on each field, returning true only if all pass.
+// With no arguments it validates every field tracked on this context.
+func (c *Context) ValidateAll(fields ...*Field) bool {
+	if len(fields) == 0 {
+		fields = c.fields
+	}
+	ok := true
+	for _, f := range fields {
+		if !f.Validate() {
+			ok = false
+		}
+	}
+	return ok
+}
+
+// ResetFields resets each field to its initial value and clears errors.
+// With no arguments it resets every field tracked on this context.
+func (c *Context) ResetFields(fields ...*Field) {
+	if len(fields) == 0 {
+		fields = c.fields
+	}
+	for _, f := range fields {
+		f.Reset()
+	}
+}
+
 func newContext(id string, route string, v *V) *Context {
 	if v == nil {
 		panic("create context failed: app pointer is nil")
@@ -474,12 +533,14 @@ func newContext(id string, route string, v *V) *Context {
 	return &Context{
 		id:                id,
 		route:             route,
+		csrfToken:         genCSRFToken(),
 		routeParams:       make(map[string]string),
 		app:               v,
-		componentRegistry: make(map[string]*Context),
-		actionRegistry:    make(map[string]func()),
+		actionLimiter: newLimiter(v.actionRateLimit, defaultActionRate, defaultActionBurst),
+		actionRegistry:    make(map[string]actionEntry),
 		signals:           new(sync.Map),
 		patchChan:         make(chan patch, 1),
 		ctxDisposedChan:   make(chan struct{}, 1),
+		createdAt:         time.Now(),
 	}
 }

field.go

@@ -0,0 +1,58 @@
+package via
+
+// Field is a signal with built-in validation rules and error state.
+// It embeds *signal, so all signal methods (Bind, String, Int, Bool, SetValue, Text, ID)
+// work transparently.
+type Field struct {
+	*signal
+	rules      []Rule
+	errors     []string
+	initialVal any
+}
+
+// Validate runs all rules against the current value.
+// Clears previous errors, populates new ones, returns true if all rules pass.
+func (f *Field) Validate() bool {
+	f.errors = nil
+	val := f.String()
+	for _, r := range f.rules {
+		if err := r.validate(val); err != nil {
+			f.errors = append(f.errors, err.Error())
+		}
+	}
+	return len(f.errors) == 0
+}
+
+// HasError returns true if this field has any validation errors.
+func (f *Field) HasError() bool {
+	return len(f.errors) > 0
+}
+
+// FirstError returns the first validation error message, or "" if valid.
+func (f *Field) FirstError() string {
+	if len(f.errors) > 0 {
+		return f.errors[0]
+	}
+	return ""
+}
+
+// Errors returns all current validation error messages.
+func (f *Field) Errors() []string {
+	return f.errors
+}
+
+// AddError manually adds an error message (useful for server-side or cross-field validation).
+func (f *Field) AddError(msg string) {
+	f.errors = append(f.errors, msg)
+}
+
+// ClearErrors removes all validation errors from this field.
+func (f *Field) ClearErrors() {
+	f.errors = nil
+}
+
+// Reset restores the field value to its initial value and clears all errors.
+func (f *Field) Reset() {
+	f.SetValue(f.initialVal)
+	f.errors = nil
+}

field_test.go

@@ -0,0 +1,206 @@
+package via
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/ryanhamamura/via/h"
+	"github.com/stretchr/testify/assert"
+)
+
+func newTestField(initial any, rules ...Rule) *Field {
+	v := New()
+	var f *Field
+	v.Page("/", func(c *Context) {
+		f = c.Field(initial, rules...)
+		c.View(func() h.H { return h.Div() })
+	})
+	return f
+}
+
+func TestFieldCreation(t *testing.T) {
+	f := newTestField("hello", Required())
+	assert.Equal(t, "hello", f.String())
+	assert.NotEmpty(t, f.ID())
+}
+
+func TestFieldSignalDelegation(t *testing.T) {
+	f := newTestField(42)
+	assert.Equal(t, "42", f.String())
+	assert.Equal(t, 42, f.Int())
+
+	f.SetValue("new")
+	assert.Equal(t, "new", f.String())
+
+	// Bind returns an h.H element
+	assert.NotNil(t, f.Bind())
+}
+
+func TestFieldValidateSingleRule(t *testing.T) {
+	f := newTestField("", Required())
+	assert.False(t, f.Validate())
+	assert.True(t, f.HasError())
+	assert.Equal(t, "This field is required", f.FirstError())
+
+	f.SetValue("ok")
+	assert.True(t, f.Validate())
+	assert.False(t, f.HasError())
+	assert.Equal(t, "", f.FirstError())
+}
+
+func TestFieldValidateMultipleRules(t *testing.T) {
+	f := newTestField("ab", Required(), MinLen(3))
+	assert.False(t, f.Validate())
+	errs := f.Errors()
+	assert.Len(t, errs, 1)
+	assert.Equal(t, "Must be at least 3 characters", errs[0])
+
+	f.SetValue("")
+	assert.False(t, f.Validate())
+	errs = f.Errors()
+	assert.Len(t, errs, 2)
+}
+
+func TestFieldErrors(t *testing.T) {
+	f := newTestField("")
+	assert.Nil(t, f.Errors())
+	assert.False(t, f.HasError())
+	assert.Equal(t, "", f.FirstError())
+}
+
+func TestFieldAddError(t *testing.T) {
+	f := newTestField("ok")
+	f.AddError("username taken")
+	assert.True(t, f.HasError())
+	assert.Equal(t, "username taken", f.FirstError())
+	assert.Len(t, f.Errors(), 1)
+}
+
+func TestFieldClearErrors(t *testing.T) {
+	f := newTestField("", Required())
+	f.Validate()
+	assert.True(t, f.HasError())
+	f.ClearErrors()
+	assert.False(t, f.HasError())
+}
+
+func TestFieldReset(t *testing.T) {
+	f := newTestField("initial", Required(), MinLen(3))
+	f.SetValue("changed")
+	f.AddError("some error")
+
+	f.Reset()
+	assert.Equal(t, "initial", f.String())
+	assert.False(t, f.HasError())
+}
+
+func TestValidateAll(t *testing.T) {
+	v := New()
+	v.Page("/", func(c *Context) {
+		c.Field("", Required(), MinLen(3))
+		c.Field("", Required(), Email())
+		c.View(func() h.H { return h.Div() })
+
+		// both empty → both fail
+		assert.False(t, c.ValidateAll())
+	})
+
+	v2 := New()
+	v2.Page("/", func(c *Context) {
+		c.Field("joe", Required(), MinLen(3))
+		c.Field("joe@x.com", Required(), Email())
+		c.View(func() h.H { return h.Div() })
+
+		assert.True(t, c.ValidateAll())
+	})
+}
+
+func TestValidateAllPartialFailure(t *testing.T) {
+	v := New()
+	v.Page("/", func(c *Context) {
+		good := c.Field("valid", Required())
+		bad := c.Field("", Required())
+		c.View(func() h.H { return h.Div() })
+
+		ok := c.ValidateAll()
+		assert.False(t, ok)
+		assert.False(t, good.HasError())
+		assert.True(t, bad.HasError())
+	})
+}
+
+func TestValidateAllSelectiveArgs(t *testing.T) {
+	v := New()
+	v.Page("/", func(c *Context) {
+		a := c.Field("", Required())
+		b := c.Field("ok", Required())
+		cField := c.Field("", Required())
+		c.View(func() h.H { return h.Div() })
+
+		// only validate a and b — cField should be untouched
+		ok := c.ValidateAll(a, b)
+		assert.False(t, ok)
+		assert.True(t, a.HasError())
+		assert.False(t, b.HasError())
+		assert.False(t, cField.HasError(), "unselected field should not be validated")
+	})
+}
+
+func TestResetFields(t *testing.T) {
+	v := New()
+	v.Page("/", func(c *Context) {
+		a := c.Field("a", Required())
+		b := c.Field("b", Required())
+		c.View(func() h.H { return h.Div() })
+
+		a.SetValue("changed-a")
+		b.SetValue("changed-b")
+		a.AddError("err")
+
+		c.ResetFields()
+		assert.Equal(t, "a", a.String())
+		assert.Equal(t, "b", b.String())
+		assert.False(t, a.HasError())
+	})
+}
+
+func TestResetFieldsSelectiveArgs(t *testing.T) {
+	v := New()
+	v.Page("/", func(c *Context) {
+		a := c.Field("a")
+		b := c.Field("b")
+		c.View(func() h.H { return h.Div() })
+
+		a.SetValue("changed-a")
+		b.SetValue("changed-b")
+
+		// only reset a
+		c.ResetFields(a)
+		assert.Equal(t, "a", a.String())
+		assert.Equal(t, "changed-b", b.String(), "unselected field should not be reset")
+	})
+}
+
+func TestFieldValidateClearsPreviousErrors(t *testing.T) {
+	f := newTestField("", Required())
+	f.Validate()
+	assert.True(t, f.HasError())
+
+	f.SetValue("ok")
+	f.Validate()
+	assert.False(t, f.HasError())
+}
+
+func TestFieldCustomValidator(t *testing.T) {
+	f := newTestField("bad", Custom(func(val string) error {
+		if val == "bad" {
+			return fmt.Errorf("no bad words")
+		}
+		return nil
+	}))
+	assert.False(t, f.Validate())
+	assert.Equal(t, "no bad words", f.FirstError())
+
+	f.SetValue("good")
+	assert.True(t, f.Validate())
+}

go.mod

@@ -14,6 +14,7 @@ require (
 	github.com/rs/zerolog v1.34.0
 	github.com/starfederation/datastar-go v1.0.3
 	github.com/stretchr/testify v1.11.1
+	golang.org/x/time v0.14.0
 )
 
 require (
@@ -37,6 +38,6 @@ require (
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	golang.org/x/crypto v0.45.0 // indirect
 	golang.org/x/sys v0.38.0 // indirect
-	golang.org/x/time v0.14.0 // indirect
+	golang.org/x/time v0.14.0
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

internal/examples/middleware/main.go

@@ -0,0 +1,151 @@
+package main
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/ryanhamamura/via"
+	"github.com/ryanhamamura/via/h"
+)
+
+func main() {
+	v := via.New()
+	v.Config(via.Options{
+		ServerAddress: ":8080",
+		DocumentTitle: "Middleware Example",
+	})
+
+	// --- Middleware definitions ---
+
+	// requestLogger logs every page request to stdout.
+	requestLogger := func(c *via.Context, next func()) {
+		fmt.Printf("[%s] request\n", time.Now().Format("15:04:05"))
+		next()
+	}
+
+	// authRequired redirects unauthenticated users to /login.
+	authRequired := func(c *via.Context, next func()) {
+		if c.Session().GetString("role") == "" {
+			c.RedirectView("/login")
+			return
+		}
+		next()
+	}
+
+	// auditLog prints the authenticated username to stdout.
+	auditLog := func(c *via.Context, next func()) {
+		fmt.Printf("[audit] user=%s\n", c.Session().GetString("username"))
+		next()
+	}
+
+	// superAdminOnly rejects non-superadmin users with a forbidden view.
+	superAdminOnly := func(c *via.Context, next func()) {
+		if c.Session().GetString("role") != "superadmin" {
+			c.View(func() h.H {
+				return h.Div(
+					h.H1(h.Text("Forbidden")),
+					h.P(h.Text("Super-admin access required.")),
+					h.A(h.Href("/admin/dashboard"), h.Text("Back to dashboard")),
+				)
+			})
+			return
+		}
+		next()
+	}
+
+	// --- Route registration ---
+
+	v.Use(requestLogger) // global middleware
+
+	admin := v.Group("/admin", authRequired)            // prefixed group
+	admin.Use(auditLog)                                 // Group.Use()
+	superAdmin := admin.Group("/super", superAdminOnly) // nested group
+
+	// Public: redirect root to login
+	v.Page("/", func(c *via.Context) {
+		c.View(func() h.H {
+			c.Redirect("/login")
+			return h.Div()
+		})
+	})
+
+	// Public: login page with role-selection buttons
+	v.Page("/login", func(c *via.Context) {
+		loginAdmin := c.Action(func() {
+			c.Session().Set("role", "admin")
+			c.Session().Set("username", "alice")
+			c.Session().RenewToken()
+			c.Redirect("/admin/dashboard")
+		})
+
+		loginSuper := c.Action(func() {
+			c.Session().Set("role", "superadmin")
+			c.Session().Set("username", "bob")
+			c.Session().RenewToken()
+			c.Redirect("/admin/dashboard")
+		})
+
+		c.View(func() h.H {
+			return h.Div(
+				h.H1(h.Text("Login")),
+				h.P(h.Text("Choose a role:")),
+				h.Button(h.Text("Login as Admin"), loginAdmin.OnClick()),
+				h.Raw(" "),
+				h.Button(h.Text("Login as Super Admin"), loginSuper.OnClick()),
+			)
+		})
+	})
+
+	// Per-action middleware: only superadmins can invoke this action.
+	requireSuperAdmin := func(c *via.Context, next func()) {
+		if c.Session().GetString("role") != "superadmin" {
+			return
+		}
+		next()
+	}
+
+	// Admin: dashboard (requires authRequired + auditLog)
+	admin.Page("/dashboard", func(c *via.Context) {
+		logout := c.Action(func() {
+			c.Session().Delete("role")
+			c.Session().Delete("username")
+			c.Redirect("/login")
+		})
+
+		dangerAction := c.Action(func() {
+			fmt.Printf("[danger] executed by %s\n", c.Session().GetString("username"))
+			c.Sync()
+		}, via.WithMiddleware(requireSuperAdmin))
+
+		c.View(func() h.H {
+			username := c.Session().GetString("username")
+			role := c.Session().GetString("role")
+			return h.Div(
+				h.H1(h.Textf("Dashboard — %s (%s)", username, role)),
+				h.Ul(
+					h.Li(h.A(h.Href("/admin/super/settings"), h.Text("Super Admin Settings"))),
+				),
+				h.H2(h.Text("Danger Zone")),
+				h.P(h.Text("This action is protected by per-action middleware (superadmin only):")),
+				h.Button(h.Text("Delete Everything"), dangerAction.OnClick()),
+				h.Br(),
+				h.Br(),
+				h.Button(h.Text("Logout"), logout.OnClick()),
+			)
+		})
+	})
+
+	// Super-admin: settings (requires authRequired + auditLog + superAdminOnly)
+	superAdmin.Page("/settings", func(c *via.Context) {
+		c.View(func() h.H {
+			username := c.Session().GetString("username")
+			return h.Div(
+				h.H1(h.Textf("Super Admin Settings — %s", username)),
+				h.P(h.Text("Only super-admins can see this page.")),
+				h.A(h.Href("/admin/dashboard"), h.Text("Back to dashboard")),
+			)
+		})
+	})
+
+	v.Start()
+}

internal/examples/nats-chatroom/main.go

@@ -2,13 +2,11 @@ package main
 
 import (
 	"context"
-	"encoding/json"
 	"log"
 	"math/rand"
 	"sync"
 	"time"
 
-	"github.com/nats-io/nats.go"
 	"github.com/ryanhamamura/via"
 	"github.com/ryanhamamura/via/h"
 	"github.com/ryanhamamura/via/vianats"
@@ -46,15 +44,15 @@ func main() {
 	}
 	defer ps.Close()
 
-	// Create JetStream stream for message durability
-	js := ps.JetStream()
-	js.AddStream(&nats.StreamConfig{
+	err = vianats.EnsureStream(ps, vianats.StreamConfig{
 		Name:     "CHAT",
 		Subjects: []string{"chat.>"},
-		Retention: nats.LimitsPolicy,
 		MaxMsgs:  1000,
 		MaxAge:   24 * time.Hour,
 	})
+	if err != nil {
+		log.Fatalf("Failed to ensure stream: %v", err)
+	}
 
 	v := via.New()
 	v.Config(via.Options{
@@ -147,30 +145,14 @@ func main() {
 				currentSub.Unsubscribe()
 			}
 
-			// Replay history from JetStream before subscribing for real-time
 			subject := "chat.room." + room
-			if hist, err := js.SubscribeSync(subject, nats.DeliverAll(), nats.OrderedConsumer()); err == nil {
-				for {
-					msg, err := hist.NextMsg(200 * time.Millisecond)
-					if err != nil {
-						break
-					}
-					var chatMsg ChatMessage
-					if json.Unmarshal(msg.Data, &chatMsg) == nil {
-						messages = append(messages, chatMsg)
-					}
-				}
-				hist.Unsubscribe()
-				if len(messages) > 50 {
-					messages = messages[len(messages)-50:]
-				}
+
+			// Replay history from JetStream
+			if hist, err := vianats.ReplayHistory[ChatMessage](ps, subject, 50); err == nil {
+				messages = hist
 			}
 
-			sub, _ := c.Subscribe(subject, func(data []byte) {
-				var msg ChatMessage
-				if err := json.Unmarshal(data, &msg); err != nil {
-					return
-				}
+			sub, _ := via.Subscribe(c, subject, func(msg ChatMessage) {
 				messagesMu.Lock()
 				messages = append(messages, msg)
 				if len(messages) > 50 {
@@ -203,12 +185,11 @@ func main() {
 			}
 			statement.SetValue("")
 
-			data, _ := json.Marshal(ChatMessage{
+			via.Publish(c, "chat.room."+currentRoom, ChatMessage{
 				User:    currentUser,
 				Message: msg,
 				Time:    time.Now().UnixMilli(),
 			})
-			c.Publish("chat.room."+currentRoom, data)
 		})
 
 		c.View(func() h.H {

internal/examples/pubsub-crud/main.go

@@ -0,0 +1,284 @@
+package main
+
+import (
+	"context"
+	"crypto/rand"
+	"fmt"
+	"html"
+	"log"
+	"sync"
+	"time"
+
+	"github.com/ryanhamamura/via"
+	"github.com/ryanhamamura/via/h"
+	"github.com/ryanhamamura/via/vianats"
+)
+
+var WithSignal = via.WithSignal
+
+type Bookmark struct {
+	ID    string
+	Title string
+	URL   string
+}
+
+type CRUDEvent struct {
+	Action string `json:"action"`
+	Title  string `json:"title"`
+	UserID string `json:"user_id"`
+}
+
+var (
+	bookmarks   []Bookmark
+	bookmarksMu sync.RWMutex
+)
+
+func randomHex(n int) string {
+	b := make([]byte, n)
+	rand.Read(b)
+	return fmt.Sprintf("%x", b)
+}
+
+func findBookmark(id string) (Bookmark, int) {
+	for i, bm := range bookmarks {
+		if bm.ID == id {
+			return bm, i
+		}
+	}
+	return Bookmark{}, -1
+}
+
+func main() {
+	ctx := context.Background()
+
+	ps, err := vianats.New(ctx, "./data/nats")
+	if err != nil {
+		log.Fatalf("Failed to start embedded NATS: %v", err)
+	}
+	defer ps.Close()
+
+	err = vianats.EnsureStream(ps, vianats.StreamConfig{
+		Name:     "BOOKMARKS",
+		Subjects: []string{"bookmarks.>"},
+		MaxMsgs:  1000,
+		MaxAge:   24 * time.Hour,
+	})
+	if err != nil {
+		log.Fatalf("Failed to ensure stream: %v", err)
+	}
+
+	v := via.New()
+	v.Config(via.Options{
+		DevMode:       true,
+		DocumentTitle: "Bookmarks",
+		LogLevel:      via.LogLevelInfo,
+		ServerAddress: ":7331",
+		PubSub:        ps,
+	})
+
+	v.AppendToHead(
+		h.Link(h.Rel("stylesheet"), h.Href("https://cdn.jsdelivr.net/npm/daisyui@4/dist/full.min.css")),
+		h.Script(h.Src("https://cdn.tailwindcss.com")),
+	)
+
+	v.Page("/", func(c *via.Context) {
+		userID := randomHex(8)
+
+		titleSignal := c.Signal("")
+		urlSignal := c.Signal("")
+		targetIDSignal := c.Signal("")
+
+		via.Subscribe(c, "bookmarks.events", func(evt CRUDEvent) {
+			if evt.UserID == userID {
+				return
+			}
+			safeTitle := html.EscapeString(evt.Title)
+			var alertClass string
+			switch evt.Action {
+			case "created":
+				alertClass = "alert-success"
+			case "updated":
+				alertClass = "alert-info"
+			case "deleted":
+				alertClass = "alert-error"
+			}
+			c.ExecScript(fmt.Sprintf(`(function(){
+				var tc = document.getElementById('toast-container');
+				if (!tc) return;
+				var d = document.createElement('div');
+				d.className = 'alert %s';
+				d.innerHTML = '<span>Bookmark "%s" %s</span>';
+				tc.appendChild(d);
+				setTimeout(function(){ d.remove(); }, 3000);
+			})()`, alertClass, safeTitle, evt.Action))
+			c.Sync()
+		})
+
+		save := c.Action(func() {
+			title := titleSignal.String()
+			url := urlSignal.String()
+			if title == "" || url == "" {
+				return
+			}
+
+			targetID := targetIDSignal.String()
+			action := "created"
+
+			bookmarksMu.Lock()
+			if targetID != "" {
+				if _, idx := findBookmark(targetID); idx >= 0 {
+					bookmarks[idx].Title = title
+					bookmarks[idx].URL = url
+					action = "updated"
+				}
+			} else {
+				bookmarks = append(bookmarks, Bookmark{
+					ID:    randomHex(8),
+					Title: title,
+					URL:   url,
+				})
+			}
+			bookmarksMu.Unlock()
+
+			titleSignal.SetValue("")
+			urlSignal.SetValue("")
+			targetIDSignal.SetValue("")
+
+			via.Publish(c, "bookmarks.events", CRUDEvent{
+				Action: action,
+				Title:  title,
+				UserID: userID,
+			})
+			c.Sync()
+		})
+
+		edit := c.Action(func() {
+			id := targetIDSignal.String()
+			bookmarksMu.RLock()
+			bm, idx := findBookmark(id)
+			bookmarksMu.RUnlock()
+			if idx < 0 {
+				return
+			}
+			titleSignal.SetValue(bm.Title)
+			urlSignal.SetValue(bm.URL)
+		})
+
+		del := c.Action(func() {
+			id := targetIDSignal.String()
+			bookmarksMu.Lock()
+			bm, idx := findBookmark(id)
+			if idx >= 0 {
+				bookmarks = append(bookmarks[:idx], bookmarks[idx+1:]...)
+			}
+			bookmarksMu.Unlock()
+			if idx < 0 {
+				return
+			}
+
+			targetIDSignal.SetValue("")
+
+			via.Publish(c, "bookmarks.events", CRUDEvent{
+				Action: "deleted",
+				Title:  bm.Title,
+				UserID: userID,
+			})
+			c.Sync()
+		})
+
+		cancelEdit := c.Action(func() {
+			titleSignal.SetValue("")
+			urlSignal.SetValue("")
+			targetIDSignal.SetValue("")
+		})
+
+		c.View(func() h.H {
+			isEditing := targetIDSignal.String() != ""
+
+			// Build table rows
+			bookmarksMu.RLock()
+			var rows []h.H
+			for _, bm := range bookmarks {
+				rows = append(rows, h.Tr(
+					h.Td(h.Text(bm.Title)),
+					h.Td(h.A(h.Href(bm.URL), h.Attr("target", "_blank"), h.Class("link link-primary"), h.Text(bm.URL))),
+					h.Td(
+						h.Div(h.Class("flex gap-1"),
+							h.Button(h.Class("btn btn-xs btn-ghost"), h.Text("Edit"),
+								edit.OnClick(WithSignal(targetIDSignal, bm.ID)),
+							),
+							h.Button(h.Class("btn btn-xs btn-ghost text-error"), h.Text("Delete"),
+								del.OnClick(WithSignal(targetIDSignal, bm.ID)),
+							),
+						),
+					),
+				))
+			}
+			bookmarksMu.RUnlock()
+
+			saveLabel := "Add Bookmark"
+			if isEditing {
+				saveLabel = "Update Bookmark"
+			}
+
+			return h.Div(h.Class("min-h-screen bg-base-200"),
+				// Navbar
+				h.Div(h.Class("navbar bg-base-100 shadow-sm"),
+					h.Div(h.Class("flex-1"),
+						h.A(h.Class("btn btn-ghost text-xl"), h.Text("Bookmarks")),
+					),
+					h.Div(h.Class("flex-none"),
+						h.Div(h.Class("badge badge-outline"), h.Text(userID[:8])),
+					),
+				),
+
+				h.Div(h.Class("container mx-auto p-4 max-w-3xl flex flex-col gap-4"),
+					// Form card
+					h.Div(h.Class("card bg-base-100 shadow"),
+						h.Div(h.Class("card-body"),
+							h.H2(h.Class("card-title"), h.Text(saveLabel)),
+							h.Div(h.Class("flex flex-col gap-2"),
+								h.Input(h.Class("input input-bordered w-full"), h.Type("text"), h.Placeholder("Title"), titleSignal.Bind()),
+								h.Input(h.Class("input input-bordered w-full"), h.Type("text"), h.Placeholder("https://example.com"), urlSignal.Bind()),
+								h.Div(h.Class("card-actions justify-end"),
+									h.If(isEditing,
+										h.Button(h.Class("btn btn-ghost"), h.Text("Cancel"), cancelEdit.OnClick()),
+									),
+									h.Button(h.Class("btn btn-primary"), h.Text(saveLabel), save.OnClick()),
+								),
+							),
+						),
+					),
+
+					// Table card
+					h.Div(h.Class("card bg-base-100 shadow"),
+						h.Div(h.Class("card-body"),
+							h.H2(h.Class("card-title"), h.Text("All Bookmarks")),
+							h.If(len(rows) == 0,
+								h.P(h.Class("text-base-content/60"), h.Text("No bookmarks yet. Add one above!")),
+							),
+							h.If(len(rows) > 0,
+								h.Div(h.Class("overflow-x-auto"),
+									h.Table(h.Class("table"),
+										h.THead(h.Tr(
+											h.Th(h.Text("Title")),
+											h.Th(h.Text("URL")),
+											h.Th(h.Text("Actions")),
+										)),
+										h.TBody(rows...),
+									),
+								),
+							),
+						),
+					),
+				),
+
+				// Toast container — ignored by morph so Sync() doesn't wipe active toasts
+				h.Div(h.ID("toast-container"), h.Class("toast toast-end toast-top"), h.DataIgnoreMorph()),
+			)
+		})
+	})
+
+	log.Println("Starting pubsub-crud example on :7331")
+	v.Start()
+}

internal/examples/session/main.go

@@ -29,7 +29,17 @@ func main() {
 		SessionManager: sm,
 	})
 
-	// Login page
+	// Auth middleware — redirects unauthenticated users to /login
+	authRequired := func(c *via.Context, next func()) {
+		if c.Session().GetString("username") == "" {
+			c.Session().Set("flash", "Please log in first")
+			c.RedirectView("/login")
+			return
+		}
+		next()
+	}
+
+	// Login page (public)
 	v.Page("/login", func(c *via.Context) {
 		flash := c.Session().PopString("flash")
 		usernameInput := c.Signal("")
@@ -64,8 +74,10 @@ func main() {
 		})
 	})
 
-	// Dashboard page (protected)
-	v.Page("/dashboard", func(c *via.Context) {
+	// Protected pages
+	protected := v.Group("", authRequired)
+
+	protected.Page("/dashboard", func(c *via.Context) {
 		logout := c.Action(func() {
 			c.Session().Set("flash", "Goodbye!")
 			c.Session().Delete("username")
@@ -74,14 +86,6 @@ func main() {
 
 		c.View(func() h.H {
 			username := c.Session().GetString("username")
-
-			// Not logged in? Redirect to login
-			if username == "" {
-				c.Session().Set("flash", "Please log in first")
-				c.Redirect("/login")
-				return h.Div()
-			}
-
 			flash := c.Session().PopString("flash")
 			var flashMsg h.H
 			if flash != "" {

internal/examples/signup/main.go

@@ -0,0 +1,87 @@
+package main
+
+import (
+	"github.com/ryanhamamura/via"
+	"github.com/ryanhamamura/via/h"
+)
+
+func main() {
+	v := via.New()
+	v.Config(via.Options{
+		DocumentTitle: "Signup",
+		ServerAddress: ":8080",
+	})
+
+	v.AppendToHead(h.StyleEl(h.Raw(`
+		body { font-family: system-ui, sans-serif; max-width: 420px; margin: 2rem auto; padding: 0 1rem; }
+		label { display: block; font-weight: 600; margin-top: 1rem; }
+		input { display: block; width: 100%; padding: 0.4rem; margin-top: 0.25rem; box-sizing: border-box; }
+		.error { color: #c00; font-size: 0.85rem; margin-top: 0.2rem; }
+		.success { color: #080; margin-top: 1rem; }
+		.actions { margin-top: 1.5rem; display: flex; gap: 0.5rem; }
+	`)))
+
+	v.Page("/", func(c *via.Context) {
+		username := c.Field("", via.Required(), via.MinLen(3), via.MaxLen(20))
+		email := c.Field("", via.Required(), via.Email())
+		age := c.Field("", via.Required(), via.Min(13), via.Max(120))
+		// Optional field — only validated when non-empty
+		website := c.Field("", via.Pattern(`^$|^https?://\S+$`, "Must be a valid URL"))
+
+		var success string
+
+		signup := c.Action(func() {
+			success = ""
+			if !c.ValidateAll() {
+				c.Sync()
+				return
+			}
+			// Server-side check
+			if username.String() == "admin" {
+				username.AddError("Username is already taken")
+				c.Sync()
+				return
+			}
+			success = "Account created for " + username.String() + "!"
+			c.ResetFields()
+			c.Sync()
+		})
+
+		reset := c.Action(func() {
+			success = ""
+			c.ResetFields()
+			c.Sync()
+		})
+
+		c.View(func() h.H {
+			return h.Div(
+				h.H1(h.Text("Sign Up")),
+
+				h.Label(h.Text("Username")),
+				h.Input(h.Type("text"), h.Placeholder("pick a username"), username.Bind()),
+				h.If(username.HasError(), h.Div(h.Class("error"), h.Text(username.FirstError()))),
+
+				h.Label(h.Text("Email")),
+				h.Input(h.Type("email"), h.Placeholder("you@example.com"), email.Bind()),
+				h.If(email.HasError(), h.Div(h.Class("error"), h.Text(email.FirstError()))),
+
+				h.Label(h.Text("Age")),
+				h.Input(h.Type("number"), h.Placeholder("your age"), age.Bind()),
+				h.If(age.HasError(), h.Div(h.Class("error"), h.Text(age.FirstError()))),
+
+				h.Label(h.Text("Website (optional)")),
+				h.Input(h.Type("url"), h.Placeholder("https://example.com"), website.Bind()),
+				h.If(website.HasError(), h.Div(h.Class("error"), h.Text(website.FirstError()))),
+
+				h.Div(h.Class("actions"),
+					h.Button(h.Text("Sign Up"), signup.OnClick()),
+					h.Button(h.Text("Reset"), reset.OnClick()),
+				),
+
+				h.If(success != "", h.P(h.Class("success"), h.Text(success))),
+			)
+		})
+	})
+
+	v.Start()
+}

middleware.go

@@ -0,0 +1,82 @@
+package via
+
+// Middleware wraps a page init function. Call next to continue the chain;
+// return without calling next to abort (set a view first, e.g. RedirectView).
+type Middleware func(c *Context, next func())
+
+// Group is a route group with a shared prefix and middleware stack.
+type Group struct {
+	v          *V
+	prefix     string
+	middleware []Middleware
+}
+
+// Use appends middleware to the global stack.
+// Global middleware runs before every page handler.
+func (v *V) Use(mw ...Middleware) {
+	v.middleware = append(v.middleware, mw...)
+}
+
+// Group creates a route group with the given path prefix and middleware.
+// Routes registered on the group are prefixed and run the group's middleware
+// after any global middleware.
+func (v *V) Group(prefix string, mw ...Middleware) *Group {
+	return &Group{
+		v:          v,
+		prefix:     prefix,
+		middleware: mw,
+	}
+}
+
+// Page registers a route on this group. The full route is the group prefix
+// concatenated with route.
+func (g *Group) Page(route string, initContextFn func(c *Context)) {
+	fullRoute := g.prefix + route
+	allMw := make([]Middleware, 0, len(g.v.middleware)+len(g.middleware))
+	allMw = append(allMw, g.v.middleware...)
+	allMw = append(allMw, g.middleware...)
+	wrapped := chainMiddleware(allMw, initContextFn)
+	g.v.page(fullRoute, initContextFn, wrapped)
+}
+
+// Group creates a nested sub-group that inherits this group's prefix and
+// middleware, then adds its own.
+func (g *Group) Group(prefix string, mw ...Middleware) *Group {
+	combined := make([]Middleware, len(g.middleware), len(g.middleware)+len(mw))
+	copy(combined, g.middleware)
+	combined = append(combined, mw...)
+	return &Group{
+		v:          g.v,
+		prefix:     g.prefix + prefix,
+		middleware: combined,
+	}
+}
+
+// Use appends middleware to this group's stack.
+func (g *Group) Use(mw ...Middleware) {
+	g.middleware = append(g.middleware, mw...)
+}
+
+// WithMiddleware returns an ActionOption that attaches middleware to an action.
+// Action middleware runs after CSRF/rate-limit checks and signal injection.
+func WithMiddleware(mw ...Middleware) ActionOption {
+	return func(e *actionEntry) {
+		e.middleware = append(e.middleware, mw...)
+	}
+}
+
+// chainMiddleware wraps handler with the given middleware, outer-first.
+func chainMiddleware(mws []Middleware, handler func(*Context)) func(*Context) {
+	if len(mws) == 0 {
+		return handler
+	}
+	chained := handler
+	for i := len(mws) - 1; i >= 0; i-- {
+		mw := mws[i]
+		next := chained
+		chained = func(c *Context) {
+			mw(c, func() { next(c) })
+		}
+	}
+	return chained
+}

middleware_test.go

@@ -0,0 +1,340 @@
+package via
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/ryanhamamura/via/h"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMiddlewareRunsBeforeHandler(t *testing.T) {
+	var order []string
+
+	v := New()
+	v.Use(func(c *Context, next func()) {
+		order = append(order, "mw")
+		next()
+	})
+	v.Page("/", func(c *Context) {
+		order = append(order, "handler")
+		c.View(func() h.H { return h.Div() })
+	})
+
+	// Reset after registration (panic-check runs the raw handler)
+	order = nil
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/", nil))
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, []string{"mw", "handler"}, order)
+}
+
+func TestMiddlewareAbortSkipsHandler(t *testing.T) {
+	handlerCalled := false
+
+	v := New()
+	v.Use(func(c *Context, next func()) {
+		c.RedirectView("/other")
+	})
+	v.Page("/", func(c *Context) {
+		handlerCalled = true
+		c.View(func() h.H { return h.Div() })
+	})
+
+	handlerCalled = false
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/", nil))
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.False(t, handlerCalled)
+}
+
+func TestMiddlewareChainOrder(t *testing.T) {
+	var order []string
+
+	v := New()
+	for _, label := range []string{"A", "B", "C"} {
+		l := label
+		v.Use(func(c *Context, next func()) {
+			order = append(order, l)
+			next()
+		})
+	}
+	v.Page("/", func(c *Context) {
+		order = append(order, "handler")
+		c.View(func() h.H { return h.Div() })
+	})
+
+	order = nil
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/", nil))
+
+	assert.Equal(t, []string{"A", "B", "C", "handler"}, order)
+}
+
+func TestGroupPrefixRouting(t *testing.T) {
+	v := New()
+	g := v.Group("/admin")
+	g.Page("/dashboard", func(c *Context) {
+		c.View(func() h.H { return h.Div(h.Text("admin dashboard")) })
+	})
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/admin/dashboard", nil))
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "admin dashboard")
+}
+
+func TestGroupMiddlewareAppliesToGroupOnly(t *testing.T) {
+	var groupMwCalled bool
+
+	v := New()
+	g := v.Group("/admin", func(c *Context, next func()) {
+		groupMwCalled = true
+		next()
+	})
+	g.Page("/panel", func(c *Context) {
+		c.View(func() h.H { return h.Div(h.Text("panel")) })
+	})
+	v.Page("/public", func(c *Context) {
+		c.View(func() h.H { return h.Div(h.Text("public")) })
+	})
+
+	// Hit public page — group middleware should NOT run
+	groupMwCalled = false
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/public", nil))
+	assert.False(t, groupMwCalled)
+	assert.Contains(t, w.Body.String(), "public")
+
+	// Hit group page — group middleware should run
+	groupMwCalled = false
+	w = httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/admin/panel", nil))
+	assert.True(t, groupMwCalled)
+	assert.Contains(t, w.Body.String(), "panel")
+}
+
+func TestGlobalMiddlewareAppliesToGroupPages(t *testing.T) {
+	var globalCalled bool
+
+	v := New()
+	v.Use(func(c *Context, next func()) {
+		globalCalled = true
+		next()
+	})
+	g := v.Group("/admin")
+	g.Page("/dash", func(c *Context) {
+		c.View(func() h.H { return h.Div(h.Text("dash")) })
+	})
+
+	globalCalled = false
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/admin/dash", nil))
+
+	assert.True(t, globalCalled)
+	assert.Contains(t, w.Body.String(), "dash")
+}
+
+func TestNestedGroupInheritsPrefixAndMiddleware(t *testing.T) {
+	var order []string
+
+	v := New()
+	admin := v.Group("/admin", func(c *Context, next func()) {
+		order = append(order, "admin")
+		next()
+	})
+	superAdmin := admin.Group("/super", func(c *Context, next func()) {
+		order = append(order, "super")
+		next()
+	})
+	superAdmin.Page("/secret", func(c *Context) {
+		order = append(order, "handler")
+		c.View(func() h.H { return h.Div(h.Text("secret")) })
+	})
+
+	order = nil
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/admin/super/secret", nil))
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, []string{"admin", "super", "handler"}, order)
+	assert.Contains(t, w.Body.String(), "secret")
+}
+
+func TestGroupUse(t *testing.T) {
+	var order []string
+
+	v := New()
+	g := v.Group("/api")
+	g.Use(func(c *Context, next func()) {
+		order = append(order, "added-later")
+		next()
+	})
+	g.Page("/items", func(c *Context) {
+		order = append(order, "handler")
+		c.View(func() h.H { return h.Div() })
+	})
+
+	order = nil
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/api/items", nil))
+
+	assert.Equal(t, []string{"added-later", "handler"}, order)
+}
+
+func TestRedirectViewSetsValidView(t *testing.T) {
+	v := New()
+	v.Page("/test", func(c *Context) {
+		c.RedirectView("/somewhere")
+	})
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/test", nil))
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Contains(t, w.Body.String(), "<!doctype html>")
+}
+
+func TestGlobalAndGroupMiddlewareOrder(t *testing.T) {
+	var order []string
+
+	v := New()
+	v.Use(func(c *Context, next func()) {
+		order = append(order, "global")
+		next()
+	})
+	g := v.Group("/g", func(c *Context, next func()) {
+		order = append(order, "group")
+		next()
+	})
+	g.Page("/page", func(c *Context) {
+		order = append(order, "handler")
+		c.View(func() h.H { return h.Div() })
+	})
+
+	order = nil
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/g/page", nil))
+
+	assert.Equal(t, []string{"global", "group", "handler"}, order)
+}
+
+// --- Action middleware tests ---
+
+func TestActionMiddlewareRunsBeforeAction(t *testing.T) {
+	var order []string
+
+	v := New()
+	c := newContext("test", "/", v)
+
+	mw := func(_ *Context, next func()) {
+		order = append(order, "mw")
+		next()
+	}
+
+	trigger := c.Action(func() {
+		order = append(order, "action")
+	}, WithMiddleware(mw))
+
+	entry, err := c.getAction(trigger.id)
+	assert.NoError(t, err)
+
+	chainMiddleware(entry.middleware, func(_ *Context) { entry.fn() })(c)
+
+	assert.Equal(t, []string{"mw", "action"}, order)
+}
+
+func TestActionMiddlewareAbortSkipsAction(t *testing.T) {
+	actionCalled := false
+
+	v := New()
+	c := newContext("test", "/", v)
+
+	mw := func(_ *Context, next func()) {
+		// don't call next — action should not run
+	}
+
+	trigger := c.Action(func() {
+		actionCalled = true
+	}, WithMiddleware(mw))
+
+	entry, err := c.getAction(trigger.id)
+	assert.NoError(t, err)
+
+	chainMiddleware(entry.middleware, func(_ *Context) { entry.fn() })(c)
+
+	assert.False(t, actionCalled)
+}
+
+func TestActionMiddlewareChainOrder(t *testing.T) {
+	var order []string
+
+	v := New()
+	c := newContext("test", "/", v)
+
+	var mws []Middleware
+	for _, label := range []string{"A", "B", "C"} {
+		l := label
+		mws = append(mws, func(_ *Context, next func()) {
+			order = append(order, l)
+			next()
+		})
+	}
+
+	trigger := c.Action(func() {
+		order = append(order, "action")
+	}, WithMiddleware(mws...))
+
+	entry, err := c.getAction(trigger.id)
+	assert.NoError(t, err)
+
+	chainMiddleware(entry.middleware, func(_ *Context) { entry.fn() })(c)
+
+	assert.Equal(t, []string{"A", "B", "C", "action"}, order)
+}
+
+func TestActionMiddlewareCombinedWithRateLimit(t *testing.T) {
+	v := New()
+	c := newContext("test", "/", v)
+
+	mw := func(_ *Context, next func()) { next() }
+
+	trigger := c.Action(func() {}, WithRateLimit(5, 10), WithMiddleware(mw))
+
+	entry, err := c.getAction(trigger.id)
+	assert.NoError(t, err)
+	assert.NotNil(t, entry.limiter)
+	assert.Len(t, entry.middleware, 1)
+}
+
+func TestGroupWithEmptyPrefix(t *testing.T) {
+	var mwCalled bool
+
+	v := New()
+	g := v.Group("", func(c *Context, next func()) {
+		mwCalled = true
+		next()
+	})
+	g.Page("/dashboard", func(c *Context) {
+		c.View(func() h.H { return h.Div(h.Text("dash")) })
+	})
+
+	mwCalled = false
+
+	w := httptest.NewRecorder()
+	v.mux.ServeHTTP(w, httptest.NewRequest("GET", "/dashboard", nil))
+
+	assert.True(t, mwCalled)
+	assert.Contains(t, w.Body.String(), "dash")
+}

pubsub_helpers.go

@@ -0,0 +1,23 @@
+package via
+
+import "encoding/json"
+
+// Publish JSON-marshals msg and publishes to subject.
+func Publish[T any](c *Context, subject string, msg T) error {
+	data, err := json.Marshal(msg)
+	if err != nil {
+		return err
+	}
+	return c.Publish(subject, data)
+}
+
+// Subscribe JSON-unmarshals each message as T and calls handler.
+func Subscribe[T any](c *Context, subject string, handler func(T)) (Subscription, error) {
+	return c.Subscribe(subject, func(data []byte) {
+		var msg T
+		if err := json.Unmarshal(data, &msg); err != nil {
+			return
+		}
+		handler(msg)
+	})
+}

pubsub_helpers_test.go

@@ -0,0 +1,66 @@
+package via
+
+import (
+	"sync"
+	"testing"
+
+	"github.com/ryanhamamura/via/h"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestPublishSubscribe_RoundTrip(t *testing.T) {
+	ps := newMockPubSub()
+	v := New()
+	v.Config(Options{PubSub: ps})
+
+	type event struct {
+		Name  string `json:"name"`
+		Count int    `json:"count"`
+	}
+
+	var got event
+	var wg sync.WaitGroup
+	wg.Add(1)
+
+	c := newContext("typed-ctx", "/", v)
+	c.View(func() h.H { return h.Div() })
+
+	_, err := Subscribe(c, "events", func(e event) {
+		got = e
+		wg.Done()
+	})
+	require.NoError(t, err)
+
+	err = Publish(c, "events", event{Name: "click", Count: 42})
+	require.NoError(t, err)
+
+	wg.Wait()
+	assert.Equal(t, "click", got.Name)
+	assert.Equal(t, 42, got.Count)
+}
+
+func TestSubscribe_SkipsBadJSON(t *testing.T) {
+	ps := newMockPubSub()
+	v := New()
+	v.Config(Options{PubSub: ps})
+
+	type msg struct {
+		Text string `json:"text"`
+	}
+
+	called := false
+	c := newContext("bad-json-ctx", "/", v)
+	c.View(func() h.H { return h.Div() })
+
+	_, err := Subscribe(c, "topic", func(m msg) {
+		called = true
+	})
+	require.NoError(t, err)
+
+	// Publish raw invalid JSON — handler should silently skip
+	err = c.Publish("topic", []byte("not json"))
+	require.NoError(t, err)
+
+	assert.False(t, called)
+}

ratelimit.go

@@ -0,0 +1,49 @@
+package via
+
+import "golang.org/x/time/rate"
+
+const (
+	defaultActionRate  float64 = 10.0
+	defaultActionBurst int     = 20
+)
+
+// RateLimitConfig configures token-bucket rate limiting for actions.
+// Zero values fall back to defaults. Rate of -1 disables limiting entirely.
+type RateLimitConfig struct {
+	Rate  float64
+	Burst int
+}
+
+// ActionOption configures per-action behaviour when passed to Context.Action.
+type ActionOption func(*actionEntry)
+
+type actionEntry struct {
+	fn         func()
+	limiter    *rate.Limiter // nil = use context default
+	middleware []Middleware
+}
+
+// WithRateLimit returns an ActionOption that gives this action its own
+// token-bucket limiter, overriding the context-level default.
+func WithRateLimit(r float64, burst int) ActionOption {
+	return func(e *actionEntry) {
+		e.limiter = newLimiter(RateLimitConfig{Rate: r, Burst: burst}, defaultActionRate, defaultActionBurst)
+	}
+}
+
+// newLimiter creates a *rate.Limiter from cfg, substituting defaults for zero
+// values. A Rate of -1 disables limiting (returns nil).
+func newLimiter(cfg RateLimitConfig, defaultRate float64, defaultBurst int) *rate.Limiter {
+	r := cfg.Rate
+	b := cfg.Burst
+	if r == -1 {
+		return nil
+	}
+	if r == 0 {
+		r = defaultRate
+	}
+	if b == 0 {
+		b = defaultBurst
+	}
+	return rate.NewLimiter(rate.Limit(r), b)
+}

ratelimit_test.go

@@ -0,0 +1,101 @@
+package via
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestNewLimiter_Defaults(t *testing.T) {
+	l := newLimiter(RateLimitConfig{}, defaultActionRate, defaultActionBurst)
+	require.NotNil(t, l)
+	assert.InDelta(t, defaultActionRate, float64(l.Limit()), 0.001)
+	assert.Equal(t, defaultActionBurst, l.Burst())
+}
+
+func TestNewLimiter_CustomValues(t *testing.T) {
+	l := newLimiter(RateLimitConfig{Rate: 5, Burst: 10}, defaultActionRate, defaultActionBurst)
+	require.NotNil(t, l)
+	assert.InDelta(t, 5.0, float64(l.Limit()), 0.001)
+	assert.Equal(t, 10, l.Burst())
+}
+
+func TestNewLimiter_DisabledWithNegativeRate(t *testing.T) {
+	l := newLimiter(RateLimitConfig{Rate: -1}, defaultActionRate, defaultActionBurst)
+	assert.Nil(t, l)
+}
+
+func TestTokenBucket_AllowsBurstThenRejects(t *testing.T) {
+	l := newLimiter(RateLimitConfig{Rate: 1, Burst: 3}, 1, 3)
+	require.NotNil(t, l)
+
+	for i := 0; i < 3; i++ {
+		assert.True(t, l.Allow(), "request %d should be allowed within burst", i)
+	}
+	assert.False(t, l.Allow(), "request beyond burst should be rejected")
+}
+
+func TestWithRateLimit_CreatesLimiter(t *testing.T) {
+	entry := actionEntry{fn: func() {}}
+	opt := WithRateLimit(2, 4)
+	opt(&entry)
+
+	require.NotNil(t, entry.limiter)
+	assert.InDelta(t, 2.0, float64(entry.limiter.Limit()), 0.001)
+	assert.Equal(t, 4, entry.limiter.Burst())
+}
+
+func TestContextAction_WithRateLimit(t *testing.T) {
+	v := New()
+	c := newContext("test-rl", "/", v)
+
+	called := false
+	c.Action(func() { called = true }, WithRateLimit(1, 2))
+
+	// Verify the entry has its own limiter
+	for _, entry := range c.actionRegistry {
+		require.NotNil(t, entry.limiter)
+		assert.InDelta(t, 1.0, float64(entry.limiter.Limit()), 0.001)
+		assert.Equal(t, 2, entry.limiter.Burst())
+	}
+	assert.False(t, called)
+}
+
+func TestContextAction_DefaultNoPerActionLimiter(t *testing.T) {
+	v := New()
+	c := newContext("test-no-rl", "/", v)
+
+	c.Action(func() {})
+
+	for _, entry := range c.actionRegistry {
+		assert.Nil(t, entry.limiter, "entry without WithRateLimit should have nil limiter")
+	}
+}
+
+func TestContextLimiter_DefaultsApplied(t *testing.T) {
+	v := New()
+	c := newContext("test-ctx-limiter", "/", v)
+
+	require.NotNil(t, c.actionLimiter)
+	assert.InDelta(t, defaultActionRate, float64(c.actionLimiter.Limit()), 0.001)
+	assert.Equal(t, defaultActionBurst, c.actionLimiter.Burst())
+}
+
+func TestContextLimiter_DisabledViaConfig(t *testing.T) {
+	v := New()
+	v.actionRateLimit = RateLimitConfig{Rate: -1}
+	c := newContext("test-disabled", "/", v)
+
+	assert.Nil(t, c.actionLimiter)
+}
+
+func TestContextLimiter_CustomConfig(t *testing.T) {
+	v := New()
+	v.Config(Options{ActionRateLimit: RateLimitConfig{Rate: 50, Burst: 100}})
+	c := newContext("test-custom", "/", v)
+
+	require.NotNil(t, c.actionLimiter)
+	assert.InDelta(t, 50.0, float64(c.actionLimiter.Limit()), 0.001)
+	assert.Equal(t, 100, c.actionLimiter.Burst())
+}

rule.go

@@ -0,0 +1,130 @@
+package via
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+// Rule defines a single validation check for a Field.
+type Rule struct {
+	validate func(val string) error
+}
+
+// Required rejects empty or whitespace-only values.
+func Required(msg ...string) Rule {
+	m := "This field is required"
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	return Rule{func(val string) error {
+		if strings.TrimSpace(val) == "" {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+// MinLen rejects values shorter than n characters.
+func MinLen(n int, msg ...string) Rule {
+	m := fmt.Sprintf("Must be at least %d characters", n)
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	return Rule{func(val string) error {
+		if utf8.RuneCountInString(val) < n {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+// MaxLen rejects values longer than n characters.
+func MaxLen(n int, msg ...string) Rule {
+	m := fmt.Sprintf("Must be at most %d characters", n)
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	return Rule{func(val string) error {
+		if utf8.RuneCountInString(val) > n {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+// Min parses the value as an integer and rejects values less than n.
+func Min(n int, msg ...string) Rule {
+	m := fmt.Sprintf("Must be at least %d", n)
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	return Rule{func(val string) error {
+		v, err := strconv.Atoi(val)
+		if err != nil {
+			return errors.New("Must be a valid number")
+		}
+		if v < n {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+// Max parses the value as an integer and rejects values greater than n.
+func Max(n int, msg ...string) Rule {
+	m := fmt.Sprintf("Must be at most %d", n)
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	return Rule{func(val string) error {
+		v, err := strconv.Atoi(val)
+		if err != nil {
+			return errors.New("Must be a valid number")
+		}
+		if v > n {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+// Pattern rejects values that don't match the regular expression re.
+func Pattern(re string, msg ...string) Rule {
+	m := "Invalid format"
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	compiled := regexp.MustCompile(re)
+	return Rule{func(val string) error {
+		if !compiled.MatchString(val) {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+var emailRegexp = regexp.MustCompile(`^[a-zA-Z0-9._%+\-]+@[a-zA-Z0-9.\-]+\.[a-zA-Z]{2,}$`)
+
+// Email rejects values that don't look like an email address.
+func Email(msg ...string) Rule {
+	m := "Invalid email address"
+	if len(msg) > 0 {
+		m = msg[0]
+	}
+	return Rule{func(val string) error {
+		if !emailRegexp.MatchString(val) {
+			return errors.New(m)
+		}
+		return nil
+	}}
+}
+
+// Custom creates a rule from a user-provided validation function.
+// The function should return nil for valid input and an error for invalid input.
+func Custom(fn func(string) error) Rule {
+	return Rule{validate: fn}
+}

rule_test.go

@@ -0,0 +1,116 @@
+package via
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRequired(t *testing.T) {
+	r := Required()
+	assert.NoError(t, r.validate("hello"))
+	assert.Error(t, r.validate(""))
+	assert.Error(t, r.validate("   "))
+}
+
+func TestRequiredCustomMessage(t *testing.T) {
+	r := Required("name needed")
+	err := r.validate("")
+	assert.EqualError(t, err, "name needed")
+}
+
+func TestMinLen(t *testing.T) {
+	r := MinLen(3)
+	assert.NoError(t, r.validate("abc"))
+	assert.NoError(t, r.validate("abcd"))
+	assert.Error(t, r.validate("ab"))
+	assert.Error(t, r.validate(""))
+}
+
+func TestMinLenCustomMessage(t *testing.T) {
+	r := MinLen(5, "too short")
+	err := r.validate("ab")
+	assert.EqualError(t, err, "too short")
+}
+
+func TestMaxLen(t *testing.T) {
+	r := MaxLen(5)
+	assert.NoError(t, r.validate("abc"))
+	assert.NoError(t, r.validate("abcde"))
+	assert.Error(t, r.validate("abcdef"))
+}
+
+func TestMaxLenCustomMessage(t *testing.T) {
+	r := MaxLen(2, "too long")
+	err := r.validate("abc")
+	assert.EqualError(t, err, "too long")
+}
+
+func TestMin(t *testing.T) {
+	r := Min(5)
+	assert.NoError(t, r.validate("5"))
+	assert.NoError(t, r.validate("10"))
+	assert.Error(t, r.validate("4"))
+	assert.Error(t, r.validate("abc"))
+}
+
+func TestMinCustomMessage(t *testing.T) {
+	r := Min(10, "need 10+")
+	err := r.validate("3")
+	assert.EqualError(t, err, "need 10+")
+}
+
+func TestMax(t *testing.T) {
+	r := Max(10)
+	assert.NoError(t, r.validate("10"))
+	assert.NoError(t, r.validate("5"))
+	assert.Error(t, r.validate("11"))
+	assert.Error(t, r.validate("abc"))
+}
+
+func TestMaxCustomMessage(t *testing.T) {
+	r := Max(5, "too big")
+	err := r.validate("6")
+	assert.EqualError(t, err, "too big")
+}
+
+func TestPattern(t *testing.T) {
+	r := Pattern(`^\d{3}$`)
+	assert.NoError(t, r.validate("123"))
+	assert.Error(t, r.validate("12"))
+	assert.Error(t, r.validate("abcd"))
+}
+
+func TestPatternCustomMessage(t *testing.T) {
+	r := Pattern(`^\d+$`, "digits only")
+	err := r.validate("abc")
+	assert.EqualError(t, err, "digits only")
+}
+
+func TestEmail(t *testing.T) {
+	r := Email()
+	assert.NoError(t, r.validate("user@example.com"))
+	assert.NoError(t, r.validate("a.b+c@foo.co"))
+	assert.Error(t, r.validate("notanemail"))
+	assert.Error(t, r.validate("@example.com"))
+	assert.Error(t, r.validate("user@"))
+	assert.Error(t, r.validate(""))
+}
+
+func TestEmailCustomMessage(t *testing.T) {
+	r := Email("bad email")
+	err := r.validate("nope")
+	assert.EqualError(t, err, "bad email")
+}
+
+func TestCustom(t *testing.T) {
+	r := Custom(func(val string) error {
+		if val != "magic" {
+			return fmt.Errorf("must be magic")
+		}
+		return nil
+	})
+	assert.NoError(t, r.validate("magic"))
+	assert.EqualError(t, r.validate("other"), "must be magic")
+}

signal.go

@@ -81,26 +81,3 @@ func (s *signal) Int() int {
 	return 0
 }
 
-// Int64 tries to read the signal value as an int64.
-// Returns the value or 0 on failure.
-func (s *signal) Int64() int64 {
-	if n, err := strconv.ParseInt(s.String(), 10, 64); err == nil {
-		return n
-	}
-	return 0
-}
-
-// Float64 tries to read the signal value as a float64.
-// Returns the value or 0.0 on failure.
-func (s *signal) Float() float64 {
-	if n, err := strconv.ParseFloat(s.String(), 64); err == nil {
-		return n
-	}
-	return 0.0
-}
-
-// Bytes tries to read the signal value as a []byte
-// Returns the value or an empty []byte on failure.
-func (s *signal) Bytes() []byte {
-	return []byte(s.String())
-}

static_test.go

@@ -0,0 +1,143 @@
+package via
+
+import (
+	"io/fs"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"testing"
+	"testing/fstest"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestStatic(t *testing.T) {
+	dir := t.TempDir()
+	os.MkdirAll(filepath.Join(dir, "sub"), 0755)
+	os.WriteFile(filepath.Join(dir, "hello.txt"), []byte("hello world"), 0644)
+	os.WriteFile(filepath.Join(dir, "sub", "nested.txt"), []byte("nested"), 0644)
+
+	v := New()
+	v.Static("/assets/", dir)
+
+	t.Run("serves file", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/assets/hello.txt", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Equal(t, "hello world", w.Body.String())
+	})
+
+	t.Run("serves nested file", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/assets/sub/nested.txt", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Equal(t, "nested", w.Body.String())
+	})
+
+	t.Run("directory listing returns 404", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/assets/", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusNotFound, w.Code)
+	})
+
+	t.Run("subdirectory listing returns 404", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/assets/sub/", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusNotFound, w.Code)
+	})
+
+	t.Run("missing file returns 404", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/assets/nope.txt", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusNotFound, w.Code)
+	})
+}
+
+func TestStaticAutoSlash(t *testing.T) {
+	dir := t.TempDir()
+	os.WriteFile(filepath.Join(dir, "ok.txt"), []byte("ok"), 0644)
+
+	v := New()
+	v.Static("/files", dir) // no trailing slash
+
+	w := httptest.NewRecorder()
+	r := httptest.NewRequest("GET", "/files/ok.txt", nil)
+	v.mux.ServeHTTP(w, r)
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, "ok", w.Body.String())
+}
+
+func TestStaticFS(t *testing.T) {
+	fsys := fstest.MapFS{
+		"style.css":        {Data: []byte("body{}")},
+		"js/app.js":        {Data: []byte("console.log('hi')")},
+	}
+
+	v := New()
+	v.StaticFS("/static/", fsys)
+
+	t.Run("serves file", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/static/style.css", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Equal(t, "body{}", w.Body.String())
+	})
+
+	t.Run("serves nested file", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/static/js/app.js", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Equal(t, "console.log('hi')", w.Body.String())
+	})
+
+	t.Run("directory listing returns 404", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/static/", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusNotFound, w.Code)
+	})
+
+	t.Run("missing file returns 404", func(t *testing.T) {
+		w := httptest.NewRecorder()
+		r := httptest.NewRequest("GET", "/static/nope.css", nil)
+		v.mux.ServeHTTP(w, r)
+
+		assert.Equal(t, http.StatusNotFound, w.Code)
+	})
+}
+
+func TestStaticFSAutoSlash(t *testing.T) {
+	fsys := fstest.MapFS{
+		"ok.txt": {Data: []byte("ok")},
+	}
+
+	v := New()
+	v.StaticFS("/embed", fsys) // no trailing slash
+
+	w := httptest.NewRecorder()
+	r := httptest.NewRequest("GET", "/embed/ok.txt", nil)
+	v.mux.ServeHTTP(w, r)
+
+	assert.Equal(t, http.StatusOK, w.Code)
+	assert.Equal(t, "ok", w.Body.String())
+}
+
+// Verify StaticFS accepts the fs.FS interface (compile-time check).
+var _ fs.FS = fstest.MapFS{}

via.go

@@ -9,11 +9,13 @@ package via
 import (
 	"context"
 	"crypto/rand"
+	"crypto/subtle"
 	_ "embed"
 	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"io"
+	"io/fs"
 	"net/http"
 	"net/url"
 	"os"
@@ -47,9 +49,12 @@ type V struct {
 	devModePageInitFnMap map[string]func(*Context)
 	sessionManager       *scs.SessionManager
 	pubsub               PubSub
+	actionRateLimit      RateLimitConfig
 	datastarPath         string
 	datastarContent      []byte
 	datastarOnce         sync.Once
+	reaperStop           chan struct{}
+	middleware           []Middleware
 }
 
 func (v *V) logEvent(evt *zerolog.Event, c *Context) *zerolog.Event {
@@ -127,6 +132,12 @@ func (v *V) Config(cfg Options) {
 	if cfg.PubSub != nil {
 		v.pubsub = cfg.PubSub
 	}
+	if cfg.ContextTTL != 0 {
+		v.cfg.ContextTTL = cfg.ContextTTL
+	}
+	if cfg.ActionRateLimit.Rate != 0 || cfg.ActionRateLimit.Burst != 0 {
+		v.actionRateLimit = cfg.ActionRateLimit
+	}
 }
 
 // AppendToHead appends the given h.H nodes to the head of the base HTML document.
@@ -160,8 +171,16 @@ func (v *V) AppendToFoot(elements ...h.H) {
 //		})
 //	})
 func (v *V) Page(route string, initContextFn func(c *Context)) {
+	wrapped := chainMiddleware(v.middleware, initContextFn)
+	v.page(route, initContextFn, wrapped)
+}
+
+// page registers a route with separate raw and wrapped init functions.
+// raw is used for the panic-check at registration time; wrapped includes
+// any middleware and is used as the live handler.
+func (v *V) page(route string, raw, wrapped func(*Context)) {
 	v.ensureDatastarHandler()
-	// check for panics
+	// check for panics using the raw handler (no middleware)
 	func() {
 		defer func() {
 			if err := recover(); err != nil {
@@ -170,14 +189,13 @@ func (v *V) Page(route string, initContextFn func(c *Context)) {
 			}
 		}()
 		c := newContext("", "", v)
-		initContextFn(c)
+		raw(c)
 		c.view()
 		c.stopAllRoutines()
 	}()
 
-	// save page init function allows devmode to restore persisted ctx later
 	if v.cfg.DevMode {
-		v.devModePageInitFnMap[route] = initContextFn
+		v.devModePageInitFnMap[route] = wrapped
 	}
 	v.mux.HandleFunc("GET "+route, http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		v.logDebug(nil, "GET %s", r.URL.String())
@@ -191,7 +209,7 @@ func (v *V) Page(route string, initContextFn func(c *Context)) {
 		c.reqCtx = r.Context()
 		routeParams := extractParams(route, r.URL.Path)
 		c.injectRouteParams(routeParams)
-		initContextFn(c)
+		wrapped(c)
 		v.registerCtx(c)
 		if v.cfg.DevMode {
 			v.devModePersist(c)
@@ -199,7 +217,7 @@ func (v *V) Page(route string, initContextFn func(c *Context)) {
 		headElements := []h.H{h.Script(h.Type("module"), h.Src(v.datastarPath))}
 		headElements = append(headElements, v.documentHeadIncludes...)
 		headElements = append(headElements,
-			h.Meta(h.Data("signals", fmt.Sprintf("{'via-ctx':'%s'}", id))),
+			h.Meta(h.Data("signals", fmt.Sprintf("{'via-ctx':'%s','via-csrf':'%s'}", id, c.csrfToken))),
 			h.Meta(h.Data("init", "@get('/_sse')")),
 			h.Meta(h.Data("init", fmt.Sprintf(`window.addEventListener('beforeunload', (evt) => {
 			navigator.sendBeacon('/_session/close', '%s');});`, c.id))),
@@ -216,7 +234,6 @@ func (v *V) Page(route string, initContextFn func(c *Context)) {
 			Title:     v.cfg.DocumentTitle,
 			Head:      headElements,
 			Body:      bodyElements,
-			HTMLAttrs: []h.H{},
 			})
 		_ = view.Render(w)
 	}))
@@ -225,17 +242,17 @@ func (v *V) Page(route string, initContextFn func(c *Context)) {
 func (v *V) registerCtx(c *Context) {
 	v.contextRegistryMutex.Lock()
 	defer v.contextRegistryMutex.Unlock()
-	if c == nil {
-		v.logErr(c, "failed to add nil context to registry")
-		return
-	}
 	v.contextRegistry[c.id] = c
 	v.logDebug(c, "new context added to registry")
-	v.logDebug(nil, "number of sessions in registry: %d", v.currSessionNum())
+	v.logDebug(nil, "number of sessions in registry: %d", len(v.contextRegistry))
 }
 
-func (v *V) currSessionNum() int {
-	return len(v.contextRegistry)
+func (v *V) cleanupCtx(c *Context) {
+	c.dispose()
+	if v.cfg.DevMode {
+		v.devModeRemovePersisted(c)
+	}
+	v.unregisterCtx(c)
 }
 
 func (v *V) unregisterCtx(c *Context) {
@@ -247,7 +264,7 @@ func (v *V) unregisterCtx(c *Context) {
 	defer v.contextRegistryMutex.Unlock()
 	v.logDebug(c, "ctx removed from registry")
 	delete(v.contextRegistry, c.id)
-	v.logDebug(nil, "number of sessions in registry: %d", v.currSessionNum())
+	v.logDebug(nil, "number of sessions in registry: %d", len(v.contextRegistry))
 }
 
 func (v *V) getCtx(id string) (*Context, error) {
@@ -259,6 +276,50 @@ func (v *V) getCtx(id string) (*Context, error) {
 	return nil, fmt.Errorf("ctx '%s' not found", id)
 }
 
+func (v *V) startReaper() {
+	ttl := v.cfg.ContextTTL
+	if ttl < 0 {
+		return
+	}
+	if ttl == 0 {
+		ttl = 30 * time.Second
+	}
+	interval := ttl / 3
+	if interval < 5*time.Second {
+		interval = 5 * time.Second
+	}
+	v.reaperStop = make(chan struct{})
+	go func() {
+		ticker := time.NewTicker(interval)
+		defer ticker.Stop()
+		for {
+			select {
+			case <-v.reaperStop:
+				return
+			case <-ticker.C:
+				v.reapOrphanedContexts(ttl)
+			}
+		}
+	}()
+}
+
+func (v *V) reapOrphanedContexts(ttl time.Duration) {
+	now := time.Now()
+	v.contextRegistryMutex.RLock()
+	var orphans []*Context
+	for _, c := range v.contextRegistry {
+		if !c.sseConnected.Load() && now.Sub(c.createdAt) > ttl {
+			orphans = append(orphans, c)
+		}
+	}
+	v.contextRegistryMutex.RUnlock()
+
+	for _, c := range orphans {
+		v.logInfo(c, "reaping orphaned context (no SSE connection after %s)", ttl)
+		v.cleanupCtx(c)
+	}
+}
+
 // Start starts the Via HTTP server and blocks until a SIGINT or SIGTERM
 // signal is received, then performs a graceful shutdown.
 func (v *V) Start() {
@@ -271,6 +332,8 @@ func (v *V) Start() {
 		Handler: handler,
 	}
 
+	v.startReaper()
+
 	errCh := make(chan error, 1)
 	go func() {
 		errCh <- v.server.ListenAndServe()
@@ -291,16 +354,15 @@ func (v *V) Start() {
 		return
 	}
 
-	v.shutdown()
+	v.Shutdown()
 }
 
 // Shutdown gracefully shuts down the server and all contexts.
 // Safe for programmatic or test use.
 func (v *V) Shutdown() {
-	v.shutdown()
+	if v.reaperStop != nil {
+		close(v.reaperStop)
 	}
-
-func (v *V) shutdown() {
 	v.logInfo(nil, "draining all contexts")
 	v.drainAllContexts()
 
@@ -346,6 +408,46 @@ func (v *V) HTTPServeMux() *http.ServeMux {
 	return v.mux
 }
 
+// Static serves files from a filesystem directory at the given URL prefix.
+//
+// Example:
+//
+//	v.Static("/assets/", "./public")
+func (v *V) Static(urlPrefix, dir string) {
+	if !strings.HasSuffix(urlPrefix, "/") {
+		urlPrefix += "/"
+	}
+	fileServer := http.StripPrefix(urlPrefix, http.FileServer(http.Dir(dir)))
+	v.mux.Handle("GET "+urlPrefix, noDirListing(fileServer))
+}
+
+// StaticFS serves files from an [fs.FS] at the given URL prefix.
+// This is useful with //go:embed filesystems.
+//
+// Example:
+//
+//	//go:embed static
+//	var staticFiles embed.FS
+//	v.StaticFS("/assets/", staticFiles)
+func (v *V) StaticFS(urlPrefix string, fsys fs.FS) {
+	if !strings.HasSuffix(urlPrefix, "/") {
+		urlPrefix += "/"
+	}
+	fileServer := http.StripPrefix(urlPrefix, http.FileServerFS(fsys))
+	v.mux.Handle("GET "+urlPrefix, noDirListing(fileServer))
+}
+
+// noDirListing wraps a file server handler to return 404 for directory requests.
+func noDirListing(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasSuffix(r.URL.Path, "/") {
+			http.NotFound(w, r)
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
 func (v *V) ensureDatastarHandler() {
 	v.datastarOnce.Do(func() {
 		v.mux.HandleFunc("GET "+v.datastarPath, func(w http.ResponseWriter, r *http.Request) {
@@ -400,10 +502,7 @@ func (v *V) devModeRemovePersisted(c *Context) {
 	}
 	file.Close()
 
-	// remove ctx to persisted list
-	if _, ok := ctxRegMap[c.id]; !ok {
 	delete(ctxRegMap, c.id)
-	}
 
 	// write persisted list to file
 	file, err = os.Create(p)
@@ -507,16 +606,16 @@ func New() *V {
 		// use last-event-id to tell if request is a sse reconnect
 		sse.Send(datastar.EventTypePatchElements, []string{}, datastar.WithSSEEventId("via"))
 
+		c.sseConnected.Store(true)
 		v.logDebug(c, "SSE connection established")
 
-		go func() {
-			c.Sync()
-		}()
+		go c.Sync()
 
 		for {
 			select {
 			case <-sse.Context().Done():
 				v.logDebug(c, "SSE connection ended")
+				v.cleanupCtx(c)
 				return
 			case <-c.ctxDisposedChan:
 				v.logDebug(c, "context disposed, closing SSE")
@@ -572,13 +671,29 @@ func New() *V {
 			v.logErr(nil, "action '%s' failed: %v", actionID, err)
 			return
 		}
+		csrfToken, _ := sigs["via-csrf"].(string)
+		if subtle.ConstantTimeCompare([]byte(csrfToken), []byte(c.csrfToken)) != 1 {
+			v.logWarn(c, "action '%s' rejected: invalid CSRF token", actionID)
+			http.Error(w, "invalid CSRF token", http.StatusForbidden)
+			return
+		}
+		if c.actionLimiter != nil && !c.actionLimiter.Allow() {
+			v.logWarn(c, "action '%s' rate limited", actionID)
+			http.Error(w, "rate limited", http.StatusTooManyRequests)
+			return
+		}
 		c.reqCtx = r.Context()
-		actionFn, err := c.getActionFn(actionID)
+		entry, err := c.getAction(actionID)
 		if err != nil {
 			v.logDebug(c, "action '%s' failed: %v", actionID, err)
 			return
 		}
-		// log err if actionFn panics
+		if entry.limiter != nil && !entry.limiter.Allow() {
+			v.logWarn(c, "action '%s' rate limited (per-action)", actionID)
+			http.Error(w, "rate limited", http.StatusTooManyRequests)
+			return
+		}
+		// log err if action panics
 		defer func() {
 			if r := recover(); r != nil {
 				v.logErr(c, "action '%s' failed: %v", actionID, r)
@@ -586,7 +701,11 @@ func New() *V {
 		}()
 
 		c.injectSignals(sigs)
-		actionFn()
+		if len(entry.middleware) > 0 {
+			chainMiddleware(entry.middleware, func(_ *Context) { entry.fn() })(c)
+		} else {
+			entry.fn()
+		}
 	})
 
 	v.mux.HandleFunc("POST /_session/close", func(w http.ResponseWriter, r *http.Request) {
@@ -603,20 +722,22 @@ func New() *V {
 			v.logErr(c, "failed to handle session close: %v", err)
 			return
 		}
-		c.dispose()
 		v.logDebug(c, "session close event triggered")
-		if v.cfg.DevMode {
-			v.devModeRemovePersisted(c)
-		}
-		v.unregisterCtx(c)
+		v.cleanupCtx(c)
 	})
 	return v
 }
 
 func genRandID() string {
+	b := make([]byte, 4)
+	rand.Read(b)
+	return hex.EncodeToString(b)
+}
+
+func genCSRFToken() string {
 	b := make([]byte, 16)
 	rand.Read(b)
-	return hex.EncodeToString(b)[:8]
+	return hex.EncodeToString(b)
 }
 
 func extractParams(pattern, path string) map[string]string {
@@ -631,7 +752,7 @@ func extractParams(pattern, path string) map[string]string {
 			key := p[i][1 : len(p[i])-1] // remove {}
 			params[key] = u[i]
 		} else if p[i] != u[i] {
-			continue
+			return nil
 		}
 	}
 	return params

via_test.go

@@ -1,9 +1,13 @@
 package via
 
 import (
+	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"os"
+	"path/filepath"
 	"testing"
+	"time"
 
 	"github.com/ryanhamamura/via/h"
 	"github.com/stretchr/testify/assert"
@@ -128,6 +132,60 @@ func TestAction(t *testing.T) {
 	assert.Contains(t, body, "/_action/")
 }
 
+func TestEventTypes(t *testing.T) {
+	tests := []struct {
+		name     string
+		attr     string
+		buildEl  func(trigger *actionTrigger) h.H
+	}{
+		{"OnSubmit", "data-on:submit", func(tr *actionTrigger) h.H { return h.Form(tr.OnSubmit()) }},
+		{"OnInput", "data-on:input", func(tr *actionTrigger) h.H { return h.Input(tr.OnInput()) }},
+		{"OnFocus", "data-on:focus", func(tr *actionTrigger) h.H { return h.Input(tr.OnFocus()) }},
+		{"OnBlur", "data-on:blur", func(tr *actionTrigger) h.H { return h.Input(tr.OnBlur()) }},
+		{"OnMouseEnter", "data-on:mouseenter", func(tr *actionTrigger) h.H { return h.Div(tr.OnMouseEnter()) }},
+		{"OnMouseLeave", "data-on:mouseleave", func(tr *actionTrigger) h.H { return h.Div(tr.OnMouseLeave()) }},
+		{"OnScroll", "data-on:scroll", func(tr *actionTrigger) h.H { return h.Div(tr.OnScroll()) }},
+		{"OnDblClick", "data-on:dblclick", func(tr *actionTrigger) h.H { return h.Div(tr.OnDblClick()) }},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var trigger *actionTrigger
+			v := New()
+			v.Page("/", func(c *Context) {
+				trigger = c.Action(func() {})
+				c.View(func() h.H { return tt.buildEl(trigger) })
+			})
+
+			req := httptest.NewRequest("GET", "/", nil)
+			w := httptest.NewRecorder()
+			v.mux.ServeHTTP(w, req)
+			body := w.Body.String()
+			assert.Contains(t, body, tt.attr)
+			assert.Contains(t, body, "/_action/"+trigger.id)
+		})
+	}
+
+	t.Run("WithSignal", func(t *testing.T) {
+		var trigger *actionTrigger
+		var sig *signal
+		v := New()
+		v.Page("/", func(c *Context) {
+			trigger = c.Action(func() {})
+			sig = c.Signal("val")
+			c.View(func() h.H {
+				return h.Div(trigger.OnDblClick(WithSignal(sig, "x")))
+			})
+		})
+
+		req := httptest.NewRequest("GET", "/", nil)
+		w := httptest.NewRecorder()
+		v.mux.ServeHTTP(w, req)
+		body := w.Body.String()
+		assert.Contains(t, body, "data-on:dblclick")
+		assert.Contains(t, body, "$"+sig.ID()+"='x'")
+	})
+}
+
 func TestOnKeyDownWithWindow(t *testing.T) {
 	var trigger *actionTrigger
 	v := New()
@@ -235,3 +293,93 @@ func TestPage_PanicsOnNoView(t *testing.T) {
 		v.Page("/", func(c *Context) {})
 	})
 }
+
+func TestReaperCleansOrphanedContexts(t *testing.T) {
+	v := New()
+	c := newContext("orphan-1", "/", v)
+	c.createdAt = time.Now().Add(-time.Minute) // created 1 min ago
+	v.registerCtx(c)
+
+	_, err := v.getCtx("orphan-1")
+	assert.NoError(t, err)
+
+	v.reapOrphanedContexts(10 * time.Second)
+
+	_, err = v.getCtx("orphan-1")
+	assert.Error(t, err, "orphaned context should have been reaped")
+}
+
+func TestReaperIgnoresConnectedContexts(t *testing.T) {
+	v := New()
+	c := newContext("connected-1", "/", v)
+	c.createdAt = time.Now().Add(-time.Minute)
+	c.sseConnected.Store(true)
+	v.registerCtx(c)
+
+	v.reapOrphanedContexts(10 * time.Second)
+
+	_, err := v.getCtx("connected-1")
+	assert.NoError(t, err, "connected context should survive reaping")
+}
+
+func TestReaperDisabledWithNegativeTTL(t *testing.T) {
+	v := New()
+	v.cfg.ContextTTL = -1
+	v.startReaper()
+	assert.Nil(t, v.reaperStop, "reaper should not start with negative TTL")
+}
+
+func TestCleanupCtxIdempotent(t *testing.T) {
+	v := New()
+	c := newContext("idempotent-1", "/", v)
+	v.registerCtx(c)
+
+	assert.NotPanics(t, func() {
+		v.cleanupCtx(c)
+		v.cleanupCtx(c)
+	})
+
+	_, err := v.getCtx("idempotent-1")
+	assert.Error(t, err, "context should be removed after cleanup")
+}
+
+func TestDevModeRemovePersistedFix(t *testing.T) {
+	v := New()
+	v.cfg.DevMode = true
+
+	dir := filepath.Join(t.TempDir(), ".via", "devmode")
+	p := filepath.Join(dir, "ctx.json")
+	assert.NoError(t, os.MkdirAll(dir, 0755))
+
+	// Write a persisted context
+	ctxRegMap := map[string]string{"test-ctx-1": "/"}
+	f, err := os.Create(p)
+	assert.NoError(t, err)
+	assert.NoError(t, json.NewEncoder(f).Encode(ctxRegMap))
+	f.Close()
+
+	// Patch devModeRemovePersisted to use our temp path by calling it
+	// directly — we need to override the path. Instead, test via the
+	// actual function by temporarily changing the working dir.
+	origDir, _ := os.Getwd()
+	assert.NoError(t, os.Chdir(t.TempDir()))
+	defer os.Chdir(origDir)
+
+	// Re-create the structure in the temp dir
+	assert.NoError(t, os.MkdirAll(filepath.Join(".via", "devmode"), 0755))
+	p2 := filepath.Join(".via", "devmode", "ctx.json")
+	f2, _ := os.Create(p2)
+	json.NewEncoder(f2).Encode(map[string]string{"test-ctx-1": "/"})
+	f2.Close()
+
+	c := newContext("test-ctx-1", "/", v)
+	v.devModeRemovePersisted(c)
+
+	// Read back and verify
+	f3, err := os.Open(p2)
+	assert.NoError(t, err)
+	defer f3.Close()
+	var result map[string]string
+	assert.NoError(t, json.NewDecoder(f3).Decode(&result))
+	assert.Empty(t, result, "persisted context should be removed")
+}

vianats/vianats.go

@@ -4,7 +4,9 @@ package vianats
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
+	"time"
 
 	"github.com/delaneyj/toolbelt/embeddednats"
 	"github.com/nats-io/nats.go"
@@ -76,3 +78,50 @@ func (n *NATS) Conn() *nats.Conn {
 func (n *NATS) JetStream() nats.JetStreamContext {
 	return n.js
 }
+
+// StreamConfig holds the parameters for creating or updating a JetStream stream.
+type StreamConfig struct {
+	Name     string
+	Subjects []string
+	MaxMsgs  int64
+	MaxAge   time.Duration
+}
+
+// EnsureStream creates or updates a JetStream stream matching cfg.
+func EnsureStream(n *NATS, cfg StreamConfig) error {
+	_, err := n.js.AddStream(&nats.StreamConfig{
+		Name:      cfg.Name,
+		Subjects:  cfg.Subjects,
+		Retention: nats.LimitsPolicy,
+		MaxMsgs:   cfg.MaxMsgs,
+		MaxAge:    cfg.MaxAge,
+	})
+	return err
+}
+
+// ReplayHistory fetches the last limit messages from subject,
+// deserializing each as T. Returns an empty slice if nothing is available.
+func ReplayHistory[T any](n *NATS, subject string, limit int) ([]T, error) {
+	sub, err := n.js.SubscribeSync(subject, nats.DeliverAll(), nats.OrderedConsumer())
+	if err != nil {
+		return nil, err
+	}
+	defer sub.Unsubscribe()
+
+	var msgs []T
+	for {
+		raw, err := sub.NextMsg(200 * time.Millisecond)
+		if err != nil {
+			break
+		}
+		var msg T
+		if json.Unmarshal(raw.Data, &msg) == nil {
+			msgs = append(msgs, msg)
+		}
+	}
+
+	if limit > 0 && len(msgs) > limit {
+		msgs = msgs[len(msgs)-limit:]
+	}
+	return msgs, nil
+}