nodejs · AndreasMadsen · AndreasMadsen · AndreasMadsen · May 29, 2017 · thlorenz
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+If any `AsyncHook` callbacks throw, the application will print the stack trace
+and exit. The exit path does follow that of an uncaught exception but
+all `uncaughtException` listeners are removed, thus forceing the process to
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+If any `AsyncHook` callbacks throw, the application will print the stack trace
+and exit. The exit path does follow that of an uncaught exception but
+all `uncaughtException` listeners are removed, thus forceing the process to
+exit. The `'exit'` callbacks will still call unless the application is run with
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+##### Printing in AsyncHooks callbacks
+
+Because printing to the console is an asynchronous operations `console.log()`
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+##### Printing in AsyncHooks callbacks
+
+Because printing to the console is an asynchronous operations `console.log()`
+will cause the AsyncHooks callbacks to write. Using `console.log()` or similar
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+The `type` is a string that represents the type of resource that caused
+`init()` to call. Generally it will be the name of the resource's constructor.
+The resource types provided by the build in Node.js modules are:
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+the user's callback is placed in a `process.nextTick()`.
+
+The graph only shows **when** a resource was created. Not **why**. So to track
+the **why** use `triggerId`.
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+For example:
+
+```js
+const server = net.createServer(conn => {
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+* Returns {undefined}
+
+Call all `before()` callbacks and let them know a new asynchronous execution
+context is being entered. If nested calls to `emitBefore()` are made the stack
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+* Returns {undefined}
+
+Call all `after()` callbacks. If nested calls to `emitBefore()` were made then
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+make sure the stack is unwound properly. Otherwise an error will be thrown.
+
+If the user's callback throws an exception then `emitAfter()` will
+automatically be called for all `id`'s on the stack if the error is handled by
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+An asynchronous resource represents an object with an associated callback.
+This callback may be called multiple times, for example, the `connection` event
+in `net.createServer`, or just a single time like in `fs.open`. A resource
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+An asynchronous resource represents an object with an associated callback.
+This callback may be called multiple times, for example, the `connection` event
+in `net.createServer`, or just a single time like in `fs.open`. A resource
+can also be closed before the callback is called. AsyncHooks does not
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+// destroy() is called when an AsyncWrap instance is destroyed.
+function destroy(id) { }
+```
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+Registers functions to be called for different lifetime events of each async
+operation.
+The callbacks `init()`/`before()`/`after()`/`destroy()` are registered via an
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+All callbacks are optional. So, for example, if only resource cleanup needs to
+be tracked then only the `destroy()` callback needs to be passed. The
+specifics of all functions that can be passed to `callbacks` is in the section
+[`Hook Callbacks`][].
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+track of what caused the asynchronous operation using the information
+provided by AsyncHooks itself. The logging should then be skipped when
+it was the logging itself that caused AsyncHooks callback to call. By
+doing this the otherwise infinite recursion is broken.
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+The `init()` hook will trigger when an `AsyncResource` is instantiated.
+
+It is important that before/after calls are unwined
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+
+// Return the trigger ID for the AsyncResource instance.
+asyncResource.triggerId();
+```
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+* arguments
+  * `type` {string} the type of ascyc event
+  * `triggerId` {number} the ID of the execution context that created this async
+    event
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+never called, causing a memory leak in the application. Of course if
+the resource doesn't depend on GC then this isn't an issue.
+
+#### `async_hooks.currentId()`
diff --git a/doc/api/async_hooks.md b/doc/api/async_hooks.md
+```js
+class DBQuery extends AsyncResource {
+  constructor(db) {
+    super();

		##### Printing in AsyncHooks callbacks

		Because printing to the console is an asynchronous operations `console.log()`

		* Returns {undefined}

		Call all `after()` callbacks. If nested calls to `emitBefore()` were made then

		The `init()` hook will trigger when an `AsyncResource` is instantiated.

		It is important that before/after calls are unwined