Added an autostart flag to defer loading

README.md

@@ -73,6 +73,7 @@ async function third (instance, opts) {
   * <a href="#use"><code>instance.<b>use()</b></code></a>
   * <a href="#after"><code>instance.<b>after()</b></code></a>
   * <a href="#ready"><code>instance.<b>ready()</b></code></a>
+  * <a href="#start"><code>instance.<b>start()</b></code></a>
   * <a href="#override"><code>instance.<b>override()</b></code></a>
   * <a href="#onClose"><code>instance.<b>onClose()</b></code></a>
   * <a href="#close"><code>instance.<b>close()</b></code></a>
@@ -81,7 +82,7 @@ async function third (instance, opts) {
 -------------------------------------------------------
 <a name="constructor"></a>
 
-### avvio([instance], [started])
+### avvio([instance], [options], [started])
 
 Starts the avvio sequence.
 As the name suggest, `instance` is the object representing your application.
@@ -107,6 +108,9 @@ server.use(function first (s, opts, cb) {
 Options:
 
 * `expose`: a key/value property to change how `use`, `after` and `ready` are exposed.
+* `autostart`: do not start loading plugins automatically, but wait for
+  a call to [`.start()`](#start)  or [`.ready()`](#ready).
+
 
 Events:
 
@@ -261,6 +265,16 @@ app.ready(function (err, context, done) {
 
 Returns the instance on which `ready` is called, to support a chainable API.
 
+If `autostart: false` is passed as an option, calling `.ready()`  will
+also start the boot sequence.
+
+-------------------------------------------------------
+<a name="start"></a>
+
+### app.start()
+
+Start the boot sequence, if it was not started yet.
+
 -------------------------------------------------------
 <a name="express"></a>
 

boot.js

@@ -88,6 +88,10 @@ function Boot (server, opts, done) {
     return instance
   }
 
+  if (opts.autostart !== false) {
+    opts.autostart = true
+  }
+
   server = server || this
 
   this._server = server
@@ -98,6 +102,7 @@ function Boot (server, opts, done) {
     this.once('start', done)
   }
 
+  this.started = false
   this.booted = false
 
   this._readyQ = fastq(this, callWithCbOrNextTick, 1)
@@ -114,34 +119,34 @@ function Boot (server, opts, done) {
   }
   this._thereIsCloseCb = false
 
-  // we init, because we need to emit "start" if no use is called
-  this._init()
+  this._doStart = null
+  const main = new Plugin(this, (s, opts, done) => {
+    this._doStart = done
+    if (opts.autostart) {
+      this.start()
+    }
+  }, opts, noop)
+
+  Plugin.loadPlugin.call(this, main, (err) => {
+    debug('root plugin ready')
+    if (err) {
+      this._error = err
+      if (this._readyQ.length() === 0) {
+        throw err
+      }
+    } else {
+      this._readyQ.resume()
+    }
+  })
 }
 
 inherits(Boot, EE)
 
-Boot.prototype._init = function () {
-  if (this.booted) {
-    throw new Error('root plugin has already booted')
-  }
+Boot.prototype.start = function () {
+  this.started = true
 
-  if (this._current.length === 0) {
-    const main = new Plugin(this, function root (s, opts, done) {
-      // we need to wait any call to use() to happen
-      process.nextTick(done)
-    }, {}, noop)
-    Plugin.loadPlugin.call(this, main, (err) => {
-      debug('root plugin ready')
-      if (err) {
-        this._error = err
-        if (this._readyQ.length() === 0) {
-          throw err
-        }
-      } else {
-        this._readyQ.resume()
-      }
-    })
-  }
+  // we need to wait any call to use() to happen
+  process.nextTick(this._doStart)
 }
 
 // allows to override the instance of a server, given a plugin
@@ -176,8 +181,9 @@ Boot.prototype._addPlugin = function (plugin, opts, callback) {
   opts = opts || {}
   callback = callback || null
 
-  // we reinit, if use is called after emitting start once
-  this._init()
+  if (this.booted) {
+    throw new Error('root plugin has already booted')
+  }
 
   // we always add plugins to load at the current element
   const current = this._current[0]
@@ -230,6 +236,7 @@ Boot.prototype.close = function (func) {
 
 Boot.prototype.ready = function (func) {
   this._readyQ.push(func)
+  this.start()
   return this
 }
 

test/basic.test.js

@@ -205,3 +205,53 @@ test('promise long resolve', (t) => {
     t.notOk(err)
   })
 })
+
+test('do not autostart', (t) => {
+  const app = boot(null, {
+    autostart: false
+  })
+  app.on('start', () => {
+    t.fail()
+  })
+  t.end()
+})
+
+test('start with ready', (t) => {
+  t.plan(2)
+
+  const app = boot(null, {
+    autostart: false
+  })
+
+  app.on('start', () => {
+    t.pass()
+  })
+
+  app.ready(function (err) {
+    t.error(err)
+  })
+})
+
+test('load a plugin after start()', (t) => {
+  t.plan(1)
+
+  var startCalled = false
+  const app = boot(null, {
+    autostart: false
+  })
+
+  app.use((s, opts, done) => {
+    t.ok(startCalled)
+    done()
+  })
+
+  // we use a timer because
+  // it is more reliable than
+  // nextTick and setImmediate
+  // this almost always will come
+  // after those are completed
+  setTimeout(() => {
+    app.start()
+    startCalled = true
+  }, 2)
+})