feat: support on-event command for watch changes

README.md

@@ -159,6 +159,7 @@ You can pass the following options via CLI arguments. You can also use `--config
 | Set the inspector host to listen on (default: loopback address or `0.0.0.0` inside Docker)                                              |               | `--debug-host`     | `FASTIFY_DEBUG_HOST`     |
 | Prints pretty logs                                                                                                                      | `-P`          | `--pretty-logs`    | `FASTIFY_PRETTY_LOGS`    |
 | Watch process.cwd() directory for changes, recursively; when that happens, the process will auto reload                                 | `-w`          | `--watch`          | `FASTIFY_WATCH`          |
+| When watch triggers a restart, run a command.                                                                                           | `-e`          | `--on-watch-event`       | `FASTIFY_ON_WATCH_EVENT ` |
 | Ignore changes to the specified files or directories when watch is enabled. (e.g. `--ignore-watch='node_modules .git logs/error.log'` ) |               | `--ignore-watch`   | `FASTIFY_IGNORE_WATCH`   |
 | Prints events triggered by watch listener (useful to debug unexpected reload when using `--watch` )                                     |     `-V`          | `--verbose-watch`  | `FASTIFY_VERBOSE_WATCH`   |
 | Use custom options                                                                                                                      | `-o`          | `--options`        | `FASTIFY_OPTIONS`        |

args.js

@@ -11,6 +11,7 @@ const DEFAULT_ARGUMENTS = {
   prettyLogs: false,
   watch: false,
   verboseWatch: false,
+  onWatchEvent: '',
   debug: false,
   debugPort: 9320,
   options: false,
@@ -27,7 +28,7 @@ module.exports = function parseArgs (args) {
       'populate--': true
     },
     number: ['port', 'inspect-port', 'body-limit', 'plugin-timeout', 'close-grace-delay'],
-    string: ['log-level', 'address', 'socket', 'prefix', 'ignore-watch', 'logging-module', 'debug-host', 'lang', 'require', 'config'],
+    string: ['log-level', 'address', 'socket', 'prefix', 'ignore-watch', 'on-watch-event', 'logging-module', 'debug-host', 'lang', 'require', 'config'],
     boolean: ['pretty-logs', 'options', 'watch', 'verbose-watch', 'debug', 'standardlint'],
     envPrefix: 'FASTIFY_',
     alias: {
@@ -41,6 +42,7 @@ module.exports = function parseArgs (args) {
       prefix: ['x'],
       require: ['r'],
       debug: ['d'],
+      'on-watch-event': ['e'],
       'debug-port': ['I'],
       'log-level': ['l'],
       'pretty-logs': ['P'],
@@ -81,6 +83,7 @@ module.exports = function parseArgs (args) {
     debugHost: parsedArgs.debugHost,
     ignoreWatch,
     verboseWatch: parsedArgs.verboseWatch,
+    onWatchEvent: parsedArgs.onWatchEvent,
     logLevel: parsedArgs.logLevel,
     address: parsedArgs.address,
     socket: parsedArgs.socket,

help/start.txt

@@ -38,6 +38,10 @@ OPTS
   [env: FASTIFY_WATCH]
       Watch process.cwd() directory for changes, recursively; when that happens, the process will auto reload.
 
+  -e, --on-watch-event
+  [env: FASTIFY_ON_WATCH_EVENT]
+      When watch triggers a restart, run a command.
+
   -x, --prefix
   [env: FASTIFY_PREFIX]
       Set the prefix

lib/watch/fork.js

@@ -1,5 +1,6 @@
 'use strict'
 
+const { execSync } = require('child_process')
 const chalk = require('chalk')
 const { stop, runFastify } = require('../../start')
 
@@ -37,6 +38,12 @@ process.on('uncaughtException', (err) => {
 })
 
 const main = async () => {
+
+  if (process.env.onWatchEvent) {
+    const output = execSync(process.env.onWatchEvent).toString()
+    process.send(output)
+  }
+
   fastify = await runFastify(process.argv.splice(2))
   const type = process.env.childEvent
 

lib/watch/index.js

@@ -10,7 +10,7 @@ const EventEmitter = require('events')
 const chokidar = require('chokidar')
 const forkPath = path.join(__dirname, './fork.js')
 
-const watch = function (args, ignoreWatch, verboseWatch) {
+const watch = function (args, ignoreWatch, verboseWatch, onWatchEvent) {
   const emitter = new EventEmitter()
   let allStop = false
   let childs = []
@@ -38,12 +38,13 @@ const watch = function (args, ignoreWatch, verboseWatch) {
   let readyEmitted = false
 
   const run = (event) => {
-    const childEvent = { childEvent: event }
+    const childEvent = { childEvent: event, onWatchEvent }
     const env = Object.assign({}, require('dotenv').config().parsed, process.env, childEvent)
     const _child = cp.fork(forkPath, args, {
       env,
       cwd: process.cwd(),
-      encoding: 'utf8'
+      encoding: 'utf8',
+      stdio: 'inherit'
     })
 
     _child.on('exit', function (code, signal) {
@@ -106,6 +107,7 @@ const watch = function (args, ignoreWatch, verboseWatch) {
   })
 
   emitter.stop = stop.bind(null, watcher)
+  emitter.childs = childs
 
   return emitter
 }

start.js

@@ -49,7 +49,7 @@ async function start (args) {
   loadModules(opts)
 
   if (opts.watch) {
-    return watch(args, opts.ignoreWatch, opts.verboseWatch)
+    return watch(args, opts.ignoreWatch, opts.verboseWatch, opts.onWatchEvent)
   }
 
   return runFastify(args)

test/args.test.js

@@ -13,6 +13,7 @@ test('should parse args correctly', t => {
     '--log-level', 'info',
     '--pretty-logs', 'true',
     '--watch', 'true',
+    '--on-watch-event', 'echo changed',
     '--ignore-watch', 'ignoreme.js',
     '--verbose-watch', 'true',
     '--options', 'true',
@@ -34,6 +35,7 @@ test('should parse args correctly', t => {
     prettyLogs: true,
     options: true,
     watch: true,
+    onWatchEvent: 'echo changed',
     ignoreWatch: 'node_modules build dist .git bower_components logs .swp .nyc_output ignoreme.js',
     verboseWatch: true,
     port: 7777,
@@ -65,6 +67,7 @@ test('should parse args with = assignment correctly', t => {
     '--log-level=info',
     '--pretty-logs=true',
     '--watch=true',
+    '--on-watch-event="echo changed"',
     '--ignore-watch=ignoreme.js',
     '--verbose-watch=true',
     '--options=true',
@@ -86,6 +89,7 @@ test('should parse args with = assignment correctly', t => {
     prettyLogs: true,
     options: true,
     watch: true,
+    onWatchEvent: 'echo changed',
     ignoreWatch: 'node_modules build dist .git bower_components logs .swp .nyc_output ignoreme.js',
     verboseWatch: true,
     port: 7777,
@@ -116,6 +120,7 @@ test('should parse env vars correctly', t => {
   process.env.FASTIFY_LOG_LEVEL = 'info'
   process.env.FASTIFY_PRETTY_LOGS = 'true'
   process.env.FASTIFY_WATCH = 'true'
+  process.env.FASTIFY_ON_WATCH_EVENT = 'echo changed'
   process.env.FASTIFY_IGNORE_WATCH = 'ignoreme.js'
   process.env.FASTIFY_VERBOSE_WATCH = 'true'
   process.env.FASTIFY_OPTIONS = 'true'
@@ -136,6 +141,7 @@ test('should parse env vars correctly', t => {
     delete process.env.FASTIFY_LOG_LEVEL
     delete process.env.FASTIFY_PRETTY_LOGS
     delete process.env.FASTIFY_WATCH
+    delete process.env.FASTIFY_ON_WATCH_EVENT
     delete process.env.FASTIFY_IGNORE_WATCH
     delete process.env.FASTIFY_VERBOSE_WATCH
     delete process.env.FASTIFY_OPTIONS
@@ -156,6 +162,7 @@ test('should parse env vars correctly', t => {
     prettyLogs: true,
     options: true,
     watch: true,
+    onWatchEvent: 'echo changed',
     ignoreWatch: 'node_modules build dist .git bower_components logs .swp .nyc_output ignoreme.js',
     verboseWatch: true,
     address: 'fastify.io:9999',
@@ -177,7 +184,7 @@ test('should parse env vars correctly', t => {
 })
 
 test('should respect default values', t => {
-  t.plan(13)
+  t.plan(14)
 
   const argv = [
     'app.js'
@@ -189,6 +196,7 @@ test('should respect default values', t => {
   t.equal(parsedArgs.options, false)
   t.equal(parsedArgs.prettyLogs, false)
   t.equal(parsedArgs.watch, false)
+  t.equal(parsedArgs.onWatchEvent, '')
   t.equal(parsedArgs.ignoreWatch, 'node_modules build dist .git bower_components logs .swp .nyc_output')
   t.equal(parsedArgs.verboseWatch, false)
   t.equal(parsedArgs.logLevel, 'fatal')
@@ -211,6 +219,7 @@ test('should parse custom plugin options', t => {
     '--log-level', 'info',
     '--pretty-logs', 'true',
     '--watch', 'true',
+    '--on-watch-event', 'echo changed',
     '--ignore-watch', 'ignoreme.js',
     '--verbose-watch', 'true',
     '--options', 'true',
@@ -239,6 +248,7 @@ test('should parse custom plugin options', t => {
     prettyLogs: true,
     options: true,
     watch: true,
+    onWatchEvent: 'echo changed',
     ignoreWatch: 'node_modules build dist .git bower_components logs .swp .nyc_output ignoreme.js',
     verboseWatch: true,
     port: 7777,
@@ -284,6 +294,7 @@ test('should parse config file correctly and prefer config values over default o
     prettyLogs: true,
     options: false,
     watch: true,
+    onWatchEvent: '',
     debug: false,
     debugPort: 4000,
     debugHost: '1.1.1.1',
@@ -323,6 +334,7 @@ test('should prefer command line args over config file options', t => {
     prettyLogs: true,
     options: false,
     watch: true,
+    onWatchEvent: '',
     debug: false,
     debugPort: 9320,
     debugHost: '1.1.1.1',

test/start.test.js

@@ -564,7 +564,7 @@ test('should start the server with watch options that the child process restart
 })
 
 test('should start the server with watch and verbose-watch options that the child process restart when directory changed with console message about changes ', { skip: process.platform === 'win32' }, async (t) => {
-  t.plan(4)
+  t.plan(5)
 
   const spy = sinon.spy()
   const watch = proxyquire('../lib/watch', {
@@ -582,7 +582,7 @@ test('should start the server with watch and verbose-watch options that the chil
   const port = getPort()
 
   await writeFile(tmpjs, 'hello world')
-  const argv = ['-p', port, '-w', '--verbose-watch', './examples/plugin.js']
+  const argv = ['-p', port, '-w', '--verbose-watch', '--on-watch-event="echo changed"', './examples/plugin.js']
   const fastifyEmitter = await start.start(argv)
 
   t.teardown(async () => {
@@ -592,12 +592,23 @@ test('should start the server with watch and verbose-watch options that the chil
     await fastifyEmitter.stop()
   })
 
+  // listen for any of the forked processes messages
+  const onChanges = new Promise((resolve, reject) => {
+    for (const child of fastifyEmitter.childs) {
+      child.on('message', resolve)
+      setTimeout(reject, 300)
+    }
+  })
+
   await once(fastifyEmitter, 'ready')
   t.pass('should receive ready event')
 
   await writeFile(tmpjs, 'hello fastify', { flag: 'a+' }) // chokidar watch can't catch change event in CI, but local test is all ok. you can remove annotation in local environment.
   t.pass('change tmpjs')
 
+  const message = await onChanges
+  t.ok(message.includes('changed'), 'forked process sends "changed" message')
+
   // this might happen more than once but does not matter in this context
   await once(fastifyEmitter, 'restart')
   t.pass('should receive restart event')