Files
archived-frankenphp/options.go
Kévin Dunglas 225ca409d3 feat: hot reload (#2031)
This patch brings hot reloading capabilities to PHP apps: in
development, the browser will automatically refresh the page when any
source file changes!
It's similar to HMR in JavaScript.

It is built on top of [the watcher
mechanism](https://frankenphp.dev/docs/config/#watching-for-file-changes)
and of the [Mercure](https://frankenphp.dev/docs/mercure/) integration.

Each time a watched file is modified, a Mercure update is sent, giving
the ability to the client to reload the page, or part of the page
(assets, images...).

Here is an example implementation:

```caddyfile
root ./public


mercure {
      subscriber_jwt {env.MERCURE_SUBSCRIBER_JWT_KEY}
      anonymous
}

php_server {
      hot_reload
}
```

```php
<?php
header('Content-Type: text/html');
?>
<!DOCTYPE html>
<html lang="en">
<head>
<title>Test</title>
<script>
    const es = new EventSource('<?=$_SERVER['FRANKENPHP_HOT_RELOAD']?>');
    es.onmessage = () => location.reload();
</script>
</head>
<body>
Hello
```

I plan to create a helper JS library to handle more advanced cases
(reloading CSS, JS, etc), similar to [HotWire
Spark](https://github.com/hotwired/spark). Be sure to attend my
SymfonyCon to learn more!

There is still room for improvement:

- Provide an option to only trigger the update without reloading the
worker for some files (ex, images, JS, CSS...)
- Support classic mode (currently, only the worker mode is supported)
- Don't reload all workers when only the files used by one change

However, this PR is working as-is and can be merged as a first step.

This patch heavily refactors the watcher module. Maybe it will be
possible to extract it as a standalone library at some point (would be
useful to add a similar feature but not tight to PHP as a Caddy module).

---------

Signed-off-by: Kévin Dunglas <kevin@dunglas.fr>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
2025-12-12 14:29:18 +01:00

248 lines
5.9 KiB
Go

package frankenphp
import (
"context"
"fmt"
"log/slog"
"time"
)
// defaultMaxConsecutiveFailures is the default maximum number of consecutive failures before panicking
const defaultMaxConsecutiveFailures = 6
// Option instances allow to configure FrankenPHP.
type Option func(h *opt) error
// WorkerOption instances allow configuring FrankenPHP worker.
type WorkerOption func(*workerOpt) error
// opt contains the available options.
//
// If you change this, also update the Caddy module and the documentation.
type opt struct {
hotReloadOpt
ctx context.Context
numThreads int
maxThreads int
workers []workerOpt
logger *slog.Logger
metrics Metrics
phpIni map[string]string
maxWaitTime time.Duration
}
type workerOpt struct {
mercureContext
name string
fileName string
num int
maxThreads int
env PreparedEnv
requestOptions []RequestOption
watch []string
maxConsecutiveFailures int
extensionWorkers *extensionWorkers
onThreadReady func(int)
onThreadShutdown func(int)
onServerStartup func()
onServerShutdown func()
}
// WithContext sets the main context to use.
func WithContext(ctx context.Context) Option {
return func(h *opt) error {
h.ctx = ctx
return nil
}
}
// WithNumThreads configures the number of PHP threads to start.
func WithNumThreads(numThreads int) Option {
return func(o *opt) error {
o.numThreads = numThreads
return nil
}
}
func WithMaxThreads(maxThreads int) Option {
return func(o *opt) error {
o.maxThreads = maxThreads
return nil
}
}
func WithMetrics(m Metrics) Option {
return func(o *opt) error {
o.metrics = m
return nil
}
}
// WithWorkers configures the PHP workers to start
func WithWorkers(name, fileName string, num int, options ...WorkerOption) Option {
return func(o *opt) error {
worker := workerOpt{
name: name,
fileName: fileName,
num: num,
env: PrepareEnv(nil),
watch: []string{},
maxConsecutiveFailures: defaultMaxConsecutiveFailures,
}
for _, option := range options {
if err := option(&worker); err != nil {
return err
}
}
o.workers = append(o.workers, worker)
return nil
}
}
// EXPERIMENTAL: WithExtensionWorkers allow extensions to create workers.
//
// A worker script with the provided name, fileName and thread count will be registered, along with additional
// configuration through WorkerOptions.
//
// Workers are designed to run indefinitely and will be gracefully shut down when FrankenPHP shuts down.
//
// Extension workers receive the lowest priority when determining thread allocations. If the requested number of threads
// cannot be allocated, then FrankenPHP will panic and provide this information to the user (who will need to allocate
// more total threads). Don't be greedy.
func WithExtensionWorkers(name, fileName string, numThreads int, options ...WorkerOption) (Workers, Option) {
w := &extensionWorkers{
name: name,
fileName: fileName,
num: numThreads,
}
w.options = append(options, withExtensionWorkers(w))
return w, WithWorkers(w.name, w.fileName, w.num, w.options...)
}
// WithLogger configures the global logger to use.
func WithLogger(l *slog.Logger) Option {
return func(o *opt) error {
o.logger = l
return nil
}
}
// WithPhpIni configures user defined PHP ini settings.
func WithPhpIni(overrides map[string]string) Option {
return func(o *opt) error {
o.phpIni = overrides
return nil
}
}
// WithMaxWaitTime configures the max time a request may be stalled waiting for a thread.
func WithMaxWaitTime(maxWaitTime time.Duration) Option {
return func(o *opt) error {
o.maxWaitTime = maxWaitTime
return nil
}
}
// WithWorkerEnv sets environment variables for the worker
func WithWorkerEnv(env map[string]string) WorkerOption {
return func(w *workerOpt) error {
w.env = PrepareEnv(env)
return nil
}
}
// WithWorkerRequestOptions sets options for the main dummy request created for the worker
func WithWorkerRequestOptions(options ...RequestOption) WorkerOption {
return func(w *workerOpt) error {
w.requestOptions = append(w.requestOptions, options...)
return nil
}
}
// WithWorkerMaxThreads sets the max number of threads for this specific worker
func WithWorkerMaxThreads(num int) WorkerOption {
return func(w *workerOpt) error {
w.maxThreads = num
return nil
}
}
// WithWorkerWatchMode sets directories to watch for file changes
func WithWorkerWatchMode(watch []string) WorkerOption {
return func(w *workerOpt) error {
w.watch = watch
return nil
}
}
// WithWorkerMaxFailures sets the maximum number of consecutive failures before panicking
func WithWorkerMaxFailures(maxFailures int) WorkerOption {
return func(w *workerOpt) error {
if maxFailures < -1 {
return fmt.Errorf("max consecutive failures must be >= -1, got %d", maxFailures)
}
w.maxConsecutiveFailures = maxFailures
return nil
}
}
func WithWorkerOnReady(f func(int)) WorkerOption {
return func(w *workerOpt) error {
w.onThreadReady = f
return nil
}
}
func WithWorkerOnShutdown(f func(int)) WorkerOption {
return func(w *workerOpt) error {
w.onThreadShutdown = f
return nil
}
}
// WithWorkerOnServerStartup adds a function to be called right after server startup. Useful for extensions.
func WithWorkerOnServerStartup(f func()) WorkerOption {
return func(w *workerOpt) error {
w.onServerStartup = f
return nil
}
}
// WithWorkerOnServerShutdown adds a function to be called right before server shutdown. Useful for extensions.
func WithWorkerOnServerShutdown(f func()) WorkerOption {
return func(w *workerOpt) error {
w.onServerShutdown = f
return nil
}
}
func withExtensionWorkers(w *extensionWorkers) WorkerOption {
return func(wo *workerOpt) error {
wo.extensionWorkers = w
return nil
}
}