12 Commits

Author SHA1 Message Date
Ryan Hamamura
2f6c5916ce docs: rewrite README with correct import paths and current feature set 2026-02-06 12:56:31 -10:00
Ryan Hamamura
0762ddbbc2 feat: add token-bucket rate limiting for action endpoints
Add per-context and per-action rate limiting using golang.org/x/time/rate.
Configure globally via Options.ActionRateLimit or per-action with
WithRateLimit(). Defaults to 10 req/s with burst of 20.
2026-02-06 11:52:07 -10:00
Ryan Hamamura
b7acfa6302 feat: add automatic CSRF protection for action calls
Generate a per-context CSRF token (128-bit, crypto/rand) and inject it
as a Datastar signal (via-csrf) alongside via-ctx. Validate with
constant-time comparison on /_action/{id} before executing, returning
403 on mismatch. Transparent to users since Datastar sends all signals
automatically.

Closes #9
2026-02-06 11:17:41 -10:00
Ryan Hamamura
8aa91c577c feat: add event types OnSubmit, OnInput, OnFocus, OnBlur, OnMouseEnter, OnMouseLeave, OnScroll, OnDblClick 2026-02-06 10:54:27 -10:00
Ryan Hamamura
6dcd54c88b fix: clean up leaked contexts on SSE disconnect and add orphan reaper
When clients disconnect without beforeunload firing (network drops,
mobile kills, crashes), contexts leaked in the registry permanently.

- Extract cleanupCtx helper for dispose/unregister sequence
- Call cleanupCtx on SSE disconnect (sse.Context().Done())
- Add background reaper for contexts where SSE never connected
- Add ContextTTL config option (default 30s, negative disables)
- Fix inverted condition in devModeRemovePersisted
2026-02-06 10:34:28 -10:00
Ryan Hamamura
2c44671d0e feat: add generic pub/sub helpers and pubsub-crud example
Add typed Publish[T] and Subscribe[T] generic helpers that handle
JSON marshaling, along with vianats.EnsureStream and ReplayHistory
helpers. Refactor nats-chatroom to use the new APIs.

Add pubsub-crud example demonstrating CRUD operations with DaisyUI
toast notifications broadcast to all connected clients via NATS.
2026-02-06 09:47:39 -10:00
Ryan Hamamura
53e5733100 feat: add keyboard grid example
8x8 grid game demonstrating OnKeyDownMap with WASD and arrow key
bindings. Arrow keys use WithPreventDefault to avoid page scrolling.
2026-02-02 08:58:03 -10:00
Ryan Hamamura
11543947bd feat: add OnKeyDownMap and WithWindow for combined key bindings
Add window-scoped keydown dispatching with per-key signal and
preventDefault options. Use comma operator instead of semicolons
in generated ternary expressions to produce valid JavaScript.
2026-02-02 08:57:59 -10:00
Ryan Hamamura
e79bb0e1b0 Revert "feat: add OnKeyDownMap and WithWindow for combined key bindings"
This reverts commit d1e8e3a2ed.
2026-02-02 08:27:07 -10:00
Ryan Hamamura
d1e8e3a2ed feat: add OnKeyDownMap and WithWindow for combined key bindings
OnKeyDownMap merges multiple key bindings into a single
data-on:keydown__window attribute via a JS ternary chain,
avoiding HTML attribute deduplication. WithWindow scopes
any keydown listener to the window object.
2026-02-02 08:23:06 -10:00
Ryan Hamamura
4a7acbb630 feat: add graceful shutdown with OS signal handling
Handle SIGINT/SIGTERM in Start() to cleanly drain all contexts,
stop goroutines, close SSE connections, and tear down PubSub.

Fix stopAllRoutines() to close() the channel instead of sending a
single value, so all listening goroutines are notified.
2026-01-31 09:22:43 -10:00
Ryan Hamamura
a7ace9099f feat: replace log with rs/zerolog for structured logging
Switch from the standard library log package to rs/zerolog with
ConsoleWriter for colorful terminal output in dev mode and JSON
output in production. Users can now provide their own logger via
Options.Logger or set the level via Options.LogLevel.
2026-01-31 08:18:24 -10:00
20 changed files with 1385 additions and 161 deletions

View File

@@ -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 doesnt 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.

View File

@@ -18,9 +18,11 @@ type ActionTriggerOption interface {
}
type triggerOpts struct {
hasSignal bool
signalID string
value string
hasSignal bool
signalID string
value string
window bool
preventDefault bool
}
type withSignalOpt struct {
@@ -34,6 +36,28 @@ func (o withSignalOpt) apply(opts *triggerOpts) {
opts.value = o.value
}
type withWindowOpt struct{}
func (o withWindowOpt) apply(opts *triggerOpts) {
opts.window = true
}
// WithWindow makes the event listener attach to the window instead of the element.
func WithWindow() ActionTriggerOption {
return withWindowOpt{}
}
type withPreventDefaultOpt struct{}
func (o withPreventDefaultOpt) apply(opts *triggerOpts) {
opts.preventDefault = true
}
// WithPreventDefault calls evt.preventDefault() for matched keys.
func WithPreventDefault() ActionTriggerOption {
return withPreventDefaultOpt{}
}
// WithSignal sets a signal value before triggering the action.
func WithSignal(sig *signal, value string) ActionTriggerOption {
return withSignalOpt{
@@ -54,7 +78,7 @@ func buildOnExpr(base string, opts *triggerOpts) string {
if !opts.hasSignal {
return base
}
return fmt.Sprintf("$%s=%s;%s", opts.signalID, opts.value, base)
return fmt.Sprintf("$%s=%s,%s", opts.signalID, opts.value, base)
}
func applyOptions(options ...ActionTriggerOption) triggerOpts {
@@ -83,6 +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")
@@ -92,5 +164,49 @@ func (a *actionTrigger) OnKeyDown(key string, options ...ActionTriggerOption) h.
if key != "" {
condition = fmt.Sprintf("evt.key==='%s' &&", key)
}
return h.Data("on:keydown", fmt.Sprintf("%s%s", condition, buildOnExpr(actionURL(a.id), &opts)))
attrName := "on:keydown"
if opts.window {
attrName = "on:keydown__window"
}
return h.Data(attrName, fmt.Sprintf("%s%s", condition, buildOnExpr(actionURL(a.id), &opts)))
}
// KeyBinding pairs a key with an action and per-binding options.
type KeyBinding struct {
Key string
Action *actionTrigger
Options []ActionTriggerOption
}
// KeyBind creates a KeyBinding for use with OnKeyDownMap.
func KeyBind(key string, action *actionTrigger, options ...ActionTriggerOption) KeyBinding {
return KeyBinding{Key: key, Action: action, Options: options}
}
// OnKeyDownMap produces a single window-scoped keydown attribute that dispatches
// to different actions based on the pressed key. Each binding can reference a
// different action and carry its own signal/preventDefault options.
func OnKeyDownMap(bindings ...KeyBinding) h.H {
if len(bindings) == 0 {
return nil
}
expr := ""
for i, b := range bindings {
opts := applyOptions(b.Options...)
branch := ""
if opts.preventDefault {
branch = "evt.preventDefault(),"
}
branch += buildOnExpr(actionURL(b.Action.id), &opts)
if i > 0 {
expr += " : "
}
expr += fmt.Sprintf("evt.key==='%s' ? (%s)", b.Key, branch)
}
expr += " : void 0"
return h.Data("on:keydown__window", expr)
}

View File

@@ -1,15 +1,19 @@
package via
import "github.com/alexedwards/scs/v2"
import (
"time"
type LogLevel int
"github.com/alexedwards/scs/v2"
"github.com/rs/zerolog"
)
const (
undefined LogLevel = iota
LogLevelError
LogLevelWarn
LogLevelInfo
LogLevelDebug
func ptr(l zerolog.Level) *zerolog.Level { return &l }
var (
LogLevelDebug = ptr(zerolog.DebugLevel)
LogLevelInfo = ptr(zerolog.InfoLevel)
LogLevelWarn = ptr(zerolog.WarnLevel)
LogLevelError = ptr(zerolog.ErrorLevel)
)
// Plugin is a func that can mutate the given *via.V app runtime. It is useful to integrate popular JS/CSS UI libraries or tools.
@@ -23,9 +27,12 @@ type Options struct {
// The http server address. e.g. ':3000'
ServerAddress string
// Level of the logs to write to stdout.
// Options: Error, Warn, Info, Debug.
LogLvl LogLevel
// LogLevel sets the minimum log level. nil keeps the default (Info).
LogLevel *zerolog.Level
// Logger overrides the default logger entirely. When set, LogLevel and
// DevMode have no effect on logging.
Logger *zerolog.Logger
// The title of the HTML document.
DocumentTitle string
@@ -49,4 +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
}

View File

@@ -5,13 +5,14 @@ import (
"context"
"encoding/json"
"fmt"
"log"
"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.
@@ -20,19 +21,24 @@ 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
subscriptions []Subscription
subsMu sync.Mutex
disposeOnce sync.Once
createdAt time.Time
sseConnected atomic.Bool
}
// View defines the UI rendered by this context.
@@ -100,26 +106,31 @@ 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
@@ -351,11 +362,23 @@ func (c *Context) ReplaceURLf(format string, a ...any) {
c.ReplaceURL(fmt.Sprintf(format, a...))
}
// stopAllRoutines stops all go routines tied to this Context preventing goroutine leaks.
// dispose idempotently tears down this context: unsubscribes all pubsub
// subscriptions and closes ctxDisposedChan to stop routines and exit the SSE loop.
func (c *Context) dispose() {
c.disposeOnce.Do(func() {
c.unsubscribeAll()
c.stopAllRoutines()
})
}
// stopAllRoutines closes ctxDisposedChan, broadcasting to all listening
// goroutines (OnIntervalRoutine, SSE loop) that this context is done.
func (c *Context) stopAllRoutines() {
select {
case c.ctxDisposedChan <- struct{}{}:
case <-c.ctxDisposedChan:
// already closed
default:
close(c.ctxDisposedChan)
}
}
@@ -456,18 +479,21 @@ func (c *Context) unsubscribeAll() {
func newContext(id string, route string, v *V) *Context {
if v == nil {
log.Fatal("create context failed: app pointer is nil")
panic("create context failed: app pointer is nil")
}
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(),
}
}

6
go.mod
View File

@@ -11,8 +11,10 @@ require (
github.com/delaneyj/toolbelt v0.9.1
github.com/mattn/go-sqlite3 v1.14.32
github.com/nats-io/nats.go v1.48.0
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 (
@@ -24,6 +26,8 @@ require (
github.com/google/go-tpm v0.9.7 // indirect
github.com/klauspost/compress v1.18.2 // indirect
github.com/kr/text v0.2.0 // indirect
github.com/mattn/go-colorable v0.1.13 // indirect
github.com/mattn/go-isatty v0.0.20 // indirect
github.com/minio/highwayhash v1.0.4-0.20251030100505-070ab1a87a76 // indirect
github.com/nats-io/jwt/v2 v2.8.0 // indirect
github.com/nats-io/nats-server/v2 v2.12.2 // indirect
@@ -34,6 +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
)

15
go.sum
View File

@@ -13,6 +13,7 @@ github.com/antithesishq/antithesis-sdk-go v0.5.0 h1:cudCFF83pDDANcXFzkQPUHHedfnn
github.com/antithesishq/antithesis-sdk-go v0.5.0/go.mod h1:IUpT2DPAKh6i/YhSbt6Gl3v2yvUZjmKncl7U91fup7E=
github.com/cenkalti/backoff v2.2.1+incompatible h1:tNowT99t7UNflLxfYYSlKYsBpXdEet03Pg2g16Swow4=
github.com/cenkalti/backoff v2.2.1+incompatible/go.mod h1:90ReRw6GdpyfrHakVjL/QHaoyV4aDUVVkXQJJJ3NXXM=
github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -20,6 +21,7 @@ github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1
github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/delaneyj/toolbelt v0.9.1 h1:QJComn2qoaQ4azl5uRkGpdHSO9e+JtoxDTXCiQHvH8o=
github.com/delaneyj/toolbelt v0.9.1/go.mod h1:eNXpPuThjTD4tpRNCBl4JEz9jdg9LpyzNuyG+stnIbs=
github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
github.com/google/brotli/go/cbrotli v0.0.0-20230829110029-ed738e842d2f h1:jopqB+UTSdJGEJT8tEqYyE29zN91fi2827oLET8tl7k=
github.com/google/brotli/go/cbrotli v0.0.0-20230829110029-ed738e842d2f/go.mod h1:nOPhAkwVliJdNTkj3gXpljmWhjc4wCaVqbMJcPKWP4s=
github.com/google/go-tpm v0.9.7 h1:u89J4tUUeDTlH8xxC3CTW7OHZjbjKoHdQ9W7gCUhtxA=
@@ -33,6 +35,12 @@ github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
github.com/mattn/go-sqlite3 v1.14.6/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
github.com/mattn/go-sqlite3 v1.14.32 h1:JD12Ag3oLy1zQA+BNn74xRgaBbdhbNIDYvQUEuuErjs=
github.com/mattn/go-sqlite3 v1.14.32/go.mod h1:Uh1q+B4BYcTPb+yiD3kU8Ct7aC0hY9fxUwlHK0RXw+Y=
@@ -50,11 +58,15 @@ github.com/nats-io/nuid v1.0.1 h1:5iA8DT8V7q8WK2EScv2padNa/rTESc1KdnPw4TC2paw=
github.com/nats-io/nuid v1.0.1/go.mod h1:19wcPz3Ph3q0Jbyiqsd0kePYG7A95tJPxeL+1OSON2c=
github.com/pierrec/lz4/v4 v4.1.18 h1:xaKrnTkyoqfh1YItXl56+6KJNVYWlEEPuAQW9xsplYQ=
github.com/pierrec/lz4/v4 v4.1.18/go.mod h1:gZWDp/Ze/IJXGXf23ltt2EXimqmTUXEy0GFuRQyBid4=
github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/rogpeppe/go-internal v1.14.1 h1:UQB4HGPB6osV0SQTLymcB4TgvyWu6ZyliaW0tI/otEQ=
github.com/rogpeppe/go-internal v1.14.1/go.mod h1:MaRKkUm5W0goXpeCfT7UZI6fk/L7L7so1lCWt35ZSgc=
github.com/rs/xid v1.6.0/go.mod h1:7XoLgs4eV+QndskICGsho+ADou8ySMSjJKDIan90Nz0=
github.com/rs/zerolog v1.34.0 h1:k43nTLIwcTVQAncfCw4KZ2VY6ukYoZaBPNOE8txlOeY=
github.com/rs/zerolog v1.34.0/go.mod h1:bJsvje4Z08ROH4Nhs5iH600c3IkWhwp44iRc54W6wYQ=
github.com/starfederation/datastar-go v1.0.3 h1:DnzgsJ6tDHDM6y5Nxsk0AGW/m8SyKch2vQg3P1xGTcU=
github.com/starfederation/datastar-go v1.0.3/go.mod h1:stm83LQkhZkwa5GzzdPEN6dLuu8FVwxIv0w1DYkbD3w=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -74,6 +86,9 @@ github.com/xyproto/randomstring v1.0.5 h1:YtlWPoRdgMu3NZtP45drfy1GKoojuR7hmRcnhZ
github.com/xyproto/randomstring v1.0.5/go.mod h1:rgmS5DeNXLivK7YprL0pY+lTuhNQW3iGxZ18UQApw/E=
golang.org/x/crypto v0.45.0 h1:jMBrvKuj23MTlT0bQEOBcAE0mjg8mK9RXFhRH6nyF3Q=
golang.org/x/crypto v0.45.0/go.mod h1:XTGrrkGJve7CYK7J8PEww4aY7gM3qMCElcJQ8n8JdX4=
golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
golang.org/x/sys v0.21.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
golang.org/x/sys v0.38.0 h1:3yZWxaJjBmCWXqhN1qh02AkOnCQ1poK6oF+a7xWL6Gc=
golang.org/x/sys v0.38.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=

View File

@@ -22,7 +22,7 @@ func main() {
v.Config(via.Options{
DevMode: true,
DocumentTitle: "ViaChat",
LogLvl: via.LogLevelInfo,
LogLevel: via.LogLevelInfo,
})
v.AppendToHead(

View File

@@ -0,0 +1,74 @@
package main
import (
"fmt"
"github.com/ryanhamamura/via"
"github.com/ryanhamamura/via/h"
)
const gridSize = 8
func main() {
v := via.New()
v.Config(via.Options{DocumentTitle: "Keyboard", ServerAddress: ":7331"})
v.Page("/", func(c *via.Context) {
x, y := 0, 0
dir := c.Signal("")
move := c.Action(func() {
switch dir.String() {
case "up":
y = max(0, y-1)
case "down":
y = min(gridSize-1, y+1)
case "left":
x = max(0, x-1)
case "right":
x = min(gridSize-1, x+1)
}
c.Sync()
})
c.View(func() h.H {
var rows []h.H
for row := range gridSize {
var cells []h.H
for col := range gridSize {
bg := "#e0e0e0"
if col == x && row == y {
bg = "#4a90d9"
}
cells = append(cells, h.Div(
h.Attr("style", fmt.Sprintf(
"width:48px;height:48px;background:%s;border:1px solid #ccc;",
bg,
)),
))
}
rows = append(rows, h.Div(
append([]h.H{h.Attr("style", "display:flex;")}, cells...)...,
))
}
return h.Div(
h.H1(h.Text("Keyboard Grid")),
h.P(h.Text("Move with WASD or arrow keys")),
h.Div(rows...),
via.OnKeyDownMap(
via.KeyBind("w", move, via.WithSignal(dir, "up")),
via.KeyBind("a", move, via.WithSignal(dir, "left")),
via.KeyBind("s", move, via.WithSignal(dir, "down")),
via.KeyBind("d", move, via.WithSignal(dir, "right")),
via.KeyBind("ArrowUp", move, via.WithSignal(dir, "up"), via.WithPreventDefault()),
via.KeyBind("ArrowLeft", move, via.WithSignal(dir, "left"), via.WithPreventDefault()),
via.KeyBind("ArrowDown", move, via.WithSignal(dir, "down"), via.WithPreventDefault()),
via.KeyBind("ArrowRight", move, via.WithSignal(dir, "right"), via.WithPreventDefault()),
),
)
})
})
v.Start()
}

View File

@@ -14,7 +14,7 @@ func main() {
v.Config(via.Options{
DocumentTitle: "Live Reload Demo",
DevMode: true,
LogLvl: via.LogLevelDebug,
LogLevel: via.LogLevelDebug,
Plugins: []via.Plugin{
// picocss.Default
},

View File

@@ -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"
@@ -46,21 +44,21 @@ func main() {
}
defer ps.Close()
// Create JetStream stream for message durability
js := ps.JetStream()
js.AddStream(&nats.StreamConfig{
Name: "CHAT",
Subjects: []string{"chat.>"},
Retention: nats.LimitsPolicy,
MaxMsgs: 1000,
MaxAge: 24 * time.Hour,
err = vianats.EnsureStream(ps, vianats.StreamConfig{
Name: "CHAT",
Subjects: []string{"chat.>"},
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: "NATS Chat",
LogLvl: via.LogLevelInfo,
LogLevel: via.LogLevelInfo,
ServerAddress: ":7331",
PubSub: ps,
})
@@ -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 {

View File

@@ -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()
}

View File

@@ -14,7 +14,7 @@ func main() {
v := via.New()
v.Config(via.Options{
LogLvl: via.LogLevelDebug,
LogLevel: via.LogLevelDebug,
DevMode: true,
Plugins: []via.Plugin{
// picocss.Default,

View File

@@ -54,7 +54,7 @@ func main() {
v.Config(via.Options{
DevMode: true,
DocumentTitle: "Search",
LogLvl: via.LogLevelWarn,
LogLevel: via.LogLevelWarn,
})
v.AppendToHead(

23
pubsub_helpers.go Normal file
View File

@@ -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)
})
}

66
pubsub_helpers_test.go Normal file
View File

@@ -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)
}

48
ratelimit.go Normal file
View File

@@ -0,0 +1,48 @@
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
}
// 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)
}

101
ratelimit_test.go Normal file
View File

@@ -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())
}

288
via.go
View File

@@ -7,21 +7,26 @@
package via
import (
"context"
"crypto/rand"
_ "embed"
"crypto/subtle"
"encoding/hex"
"encoding/json"
"fmt"
"io"
"log"
"net/http"
"net/url"
"os"
ossignal "os/signal"
"path/filepath"
"strings"
"sync"
"syscall"
"time"
"github.com/alexedwards/scs/v2"
"github.com/rs/zerolog"
"github.com/ryanhamamura/via/h"
"github.com/starfederation/datastar-go/datastar"
)
@@ -32,66 +37,70 @@ var datastarJS []byte
// V is the root application.
// It manages page routing, user sessions, and SSE connections for live updates.
type V struct {
cfg Options
mux *http.ServeMux
contextRegistry map[string]*Context
contextRegistryMutex sync.RWMutex
documentHeadIncludes []h.H
documentFootIncludes []h.H
devModePageInitFnMap map[string]func(*Context)
sessionManager *scs.SessionManager
pubsub PubSub
datastarPath string
datastarContent []byte
datastarOnce sync.Once
cfg Options
mux *http.ServeMux
server *http.Server
logger zerolog.Logger
contextRegistry map[string]*Context
contextRegistryMutex sync.RWMutex
documentHeadIncludes []h.H
documentFootIncludes []h.H
devModePageInitFnMap map[string]func(*Context)
sessionManager *scs.SessionManager
pubsub PubSub
actionRateLimit RateLimitConfig
datastarPath string
datastarContent []byte
datastarOnce sync.Once
reaperStop chan struct{}
}
func (v *V) logEvent(evt *zerolog.Event, c *Context) *zerolog.Event {
if c != nil && c.id != "" {
evt = evt.Str("via-ctx", c.id)
}
return evt
}
func (v *V) logFatal(format string, a ...any) {
log.Printf("[fatal] msg=%q", fmt.Sprintf(format, a...))
v.logEvent(v.logger.WithLevel(zerolog.FatalLevel), nil).Msgf(format, a...)
}
func (v *V) logErr(c *Context, format string, a ...any) {
cRef := ""
if c != nil && c.id != "" {
cRef = fmt.Sprintf("via-ctx=%q ", c.id)
}
log.Printf("[error] %smsg=%q", cRef, fmt.Sprintf(format, a...))
v.logEvent(v.logger.Error(), c).Msgf(format, a...)
}
func (v *V) logWarn(c *Context, format string, a ...any) {
cRef := ""
if c != nil && c.id != "" {
cRef = fmt.Sprintf("via-ctx=%q ", c.id)
}
if v.cfg.LogLvl >= LogLevelWarn {
log.Printf("[warn] %smsg=%q", cRef, fmt.Sprintf(format, a...))
}
v.logEvent(v.logger.Warn(), c).Msgf(format, a...)
}
func (v *V) logInfo(c *Context, format string, a ...any) {
cRef := ""
if c != nil && c.id != "" {
cRef = fmt.Sprintf("via-ctx=%q ", c.id)
}
if v.cfg.LogLvl >= LogLevelInfo {
log.Printf("[info] %smsg=%q", cRef, fmt.Sprintf(format, a...))
}
v.logEvent(v.logger.Info(), c).Msgf(format, a...)
}
func (v *V) logDebug(c *Context, format string, a ...any) {
cRef := ""
if c != nil && c.id != "" {
cRef = fmt.Sprintf("via-ctx=%q ", c.id)
}
if v.cfg.LogLvl == LogLevelDebug {
log.Printf("[debug] %smsg=%q", cRef, fmt.Sprintf(format, a...))
}
v.logEvent(v.logger.Debug(), c).Msgf(format, a...)
}
func newConsoleLogger(level zerolog.Level) zerolog.Logger {
return zerolog.New(zerolog.ConsoleWriter{Out: os.Stderr, TimeFormat: "15:04:05"}).
With().Timestamp().Logger().Level(level)
}
// Config overrides the default configuration with the given options.
func (v *V) Config(cfg Options) {
if cfg.LogLvl != undefined {
v.cfg.LogLvl = cfg.LogLvl
if cfg.Logger != nil {
v.logger = *cfg.Logger
} else if cfg.LogLevel != nil || cfg.DevMode != v.cfg.DevMode {
level := zerolog.InfoLevel
if cfg.LogLevel != nil {
level = *cfg.LogLevel
}
if cfg.DevMode {
v.logger = newConsoleLogger(level)
} else {
v.logger = zerolog.New(os.Stderr).With().Timestamp().Logger().Level(level)
}
}
if cfg.DocumentTitle != "" {
v.cfg.DocumentTitle = cfg.DocumentTitle
@@ -121,6 +130,12 @@ 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.
@@ -193,7 +208,7 @@ 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))),
@@ -232,6 +247,14 @@ 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) {
if c.id == "" {
v.logErr(c, "unregister ctx failed: ctx contains empty id")
@@ -253,14 +276,131 @@ func (v *V) getCtx(id string) (*Context, error) {
return nil, fmt.Errorf("ctx '%s' not found", id)
}
// Start starts the Via HTTP server on the given address.
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() {
v.logInfo(nil, "via started at [%s]", v.cfg.ServerAddress)
handler := http.Handler(v.mux)
if v.sessionManager != nil {
handler = v.sessionManager.LoadAndSave(v.mux)
}
log.Fatalf("[fatal] %v", http.ListenAndServe(v.cfg.ServerAddress, handler))
v.server = &http.Server{
Addr: v.cfg.ServerAddress,
Handler: handler,
}
v.startReaper()
errCh := make(chan error, 1)
go func() {
errCh <- v.server.ListenAndServe()
}()
v.logInfo(nil, "via started at [%s]", v.cfg.ServerAddress)
sigCh := make(chan os.Signal, 1)
ossignal.Notify(sigCh, syscall.SIGINT, syscall.SIGTERM)
select {
case sig := <-sigCh:
v.logInfo(nil, "received signal %v, shutting down", sig)
case err := <-errCh:
if err != nil && err != http.ErrServerClosed {
v.logger.Fatal().Err(err).Msg("http server failed")
}
return
}
v.shutdown()
}
// Shutdown gracefully shuts down the server and all contexts.
// Safe for programmatic or test use.
func (v *V) Shutdown() {
v.shutdown()
}
func (v *V) shutdown() {
if v.reaperStop != nil {
close(v.reaperStop)
}
v.logInfo(nil, "draining all contexts")
v.drainAllContexts()
if v.server != nil {
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
if err := v.server.Shutdown(ctx); err != nil {
v.logErr(nil, "http server shutdown error: %v", err)
}
}
if v.pubsub != nil {
if err := v.pubsub.Close(); err != nil {
v.logErr(nil, "pubsub close error: %v", err)
}
}
v.logInfo(nil, "shutdown complete")
}
func (v *V) drainAllContexts() {
v.contextRegistryMutex.Lock()
contexts := make([]*Context, 0, len(v.contextRegistry))
for _, c := range v.contextRegistry {
contexts = append(contexts, c)
}
v.contextRegistry = make(map[string]*Context)
v.contextRegistryMutex.Unlock()
for _, c := range contexts {
v.logDebug(c, "disposing context")
c.dispose()
}
v.logInfo(nil, "drained %d context(s)", len(contexts))
}
// HTTPServeMux returns the underlying HTTP request multiplexer to enable user extentions, middleware and
@@ -284,7 +424,7 @@ func (v *V) ensureDatastarHandler() {
func (v *V) devModePersist(c *Context) {
p := filepath.Join(".via", "devmode", "ctx.json")
if err := os.MkdirAll(filepath.Dir(p), 0755); err != nil {
log.Fatalf("failed to create directory for devmode files: %v", err)
v.logFatal("failed to create directory for devmode files: %v", err)
}
// load persisted list from file, or empty list if file not found
@@ -326,10 +466,7 @@ func (v *V) devModeRemovePersisted(c *Context) {
}
file.Close()
// remove ctx to persisted list
if _, ok := ctxRegMap[c.id]; !ok {
delete(ctxRegMap, c.id)
}
delete(ctxRegMap, c.id)
// write persisted list to file
file, err = os.Create(p)
@@ -398,6 +535,7 @@ func New() *V {
v := &V{
mux: mux,
logger: newConsoleLogger(zerolog.InfoLevel),
contextRegistry: make(map[string]*Context),
devModePageInitFnMap: make(map[string]func(*Context)),
sessionManager: scs.New(),
@@ -406,7 +544,6 @@ func New() *V {
cfg: Options{
DevMode: false,
ServerAddress: ":3000",
LogLvl: LogLevelInfo,
DocumentTitle: "⚡ Via",
},
}
@@ -433,6 +570,7 @@ 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() {
@@ -443,11 +581,12 @@ func New() *V {
select {
case <-sse.Context().Done():
v.logDebug(c, "SSE connection ended")
v.cleanupCtx(c)
return
case patch, ok := <-c.patchChan:
if !ok {
continue
}
case <-c.ctxDisposedChan:
v.logDebug(c, "context disposed, closing SSE")
return
case patch := <-c.patchChan:
switch patch.typ {
case patchTypeElements:
if err := sse.PatchElements(patch.content); err != nil {
@@ -498,13 +637,29 @@ 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)
@@ -512,13 +667,13 @@ func New() *V {
}()
c.injectSignals(sigs)
actionFn()
entry.fn()
})
v.mux.HandleFunc("POST /_session/close", func(w http.ResponseWriter, r *http.Request) {
body, err := io.ReadAll(r.Body)
if err != nil {
log.Printf("Error reading body: %v", err)
v.logErr(nil, "error reading body: %v", err)
w.WriteHeader(http.StatusBadRequest)
return
}
@@ -529,13 +684,8 @@ func New() *V {
v.logErr(c, "failed to handle session close: %v", err)
return
}
c.unsubscribeAll()
c.stopAllRoutines()
v.logDebug(c, "session close event triggered")
if v.cfg.DevMode {
v.devModeRemovePersisted(c)
}
v.unregisterCtx(c)
v.cleanupCtx(c)
})
return v
}
@@ -546,6 +696,12 @@ func genRandID() string {
return hex.EncodeToString(b)[:8]
}
func genCSRFToken() string {
b := make([]byte, 16)
rand.Read(b)
return hex.EncodeToString(b)
}
func extractParams(pattern, path string) map[string]string {
p := strings.Split(strings.Trim(pattern, "/"), "/")
u := strings.Split(strings.Trim(path, "/"), "/")

View File

@@ -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 +132,155 @@ 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()+"=&#39;x&#39;")
})
}
func TestOnKeyDownWithWindow(t *testing.T) {
var trigger *actionTrigger
v := New()
v.Page("/", func(c *Context) {
trigger = c.Action(func() {})
c.View(func() h.H {
return h.Div(trigger.OnKeyDown("Enter", WithWindow()))
})
})
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
v.mux.ServeHTTP(w, req)
body := w.Body.String()
assert.Contains(t, body, "data-on:keydown__window")
assert.Contains(t, body, "evt.key===&#39;Enter&#39;")
}
func TestOnKeyDownMap(t *testing.T) {
t.Run("multiple bindings with different actions", func(t *testing.T) {
var move, shoot *actionTrigger
var dir *signal
v := New()
v.Page("/", func(c *Context) {
dir = c.Signal("none")
move = c.Action(func() {})
shoot = c.Action(func() {})
c.View(func() h.H {
return h.Div(
OnKeyDownMap(
KeyBind("w", move, WithSignal(dir, "up")),
KeyBind("ArrowUp", move, WithSignal(dir, "up"), WithPreventDefault()),
KeyBind(" ", shoot, WithPreventDefault()),
),
)
})
})
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
v.mux.ServeHTTP(w, req)
body := w.Body.String()
// Single attribute, window-scoped
assert.Contains(t, body, "data-on:keydown__window")
// Key dispatching
assert.Contains(t, body, "evt.key===&#39;w&#39;")
assert.Contains(t, body, "evt.key===&#39;ArrowUp&#39;")
assert.Contains(t, body, "evt.key===&#39; &#39;")
// Different actions referenced
assert.Contains(t, body, "/_action/"+move.id)
assert.Contains(t, body, "/_action/"+shoot.id)
// preventDefault only on ArrowUp and space branches
assert.Contains(t, body, "evt.key===&#39;ArrowUp&#39; ? (evt.preventDefault()")
assert.Contains(t, body, "evt.key===&#39; &#39; ? (evt.preventDefault()")
// 'w' branch should NOT have preventDefault
assert.NotContains(t, body, "evt.key===&#39;w&#39; ? (evt.preventDefault()")
})
t.Run("WithSignal per binding", func(t *testing.T) {
var move *actionTrigger
var dir *signal
v := New()
v.Page("/", func(c *Context) {
dir = c.Signal("none")
move = c.Action(func() {})
c.View(func() h.H {
return h.Div(
OnKeyDownMap(
KeyBind("w", move, WithSignal(dir, "up")),
KeyBind("s", move, WithSignal(dir, "down")),
),
)
})
})
req := httptest.NewRequest("GET", "/", nil)
w := httptest.NewRecorder()
v.mux.ServeHTTP(w, req)
body := w.Body.String()
assert.Contains(t, body, "$"+dir.ID()+"=&#39;up&#39;")
assert.Contains(t, body, "$"+dir.ID()+"=&#39;down&#39;")
})
t.Run("empty bindings returns nil", func(t *testing.T) {
result := OnKeyDownMap()
assert.Nil(t, result)
})
}
func TestConfig(t *testing.T) {
v := New()
v.Config(Options{DocumentTitle: "Test"})
@@ -140,3 +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")
}

View File

@@ -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
}