Worker
| Module | ejs |
| Definition | class Worker |
| Inheritance | Worker  Object |
| Specified | WebWorker |
| Stability | Prototype. |
Worker Class.
Worker threads are medium-weight thread-based virtual machine instances. They run separate interpreters with tightly controlled data interchange. This class is currently being specified by the WebWorker task group (See http://www.whatwg.org/specs/web-workers/current-work/#introduction). This class is prototype and highly likely to change.
Properties
| Qualifiers | Property | Type | Description |
|---|---|---|---|
| name | String | Worker name. This name is initialized but workers can update as required. | |
| onclose | Function | Callback function invoked when the worker exits. The "this" object is set to the worker object. | |
| onerror | Function | Callback function to receive incoming error events. This is invoked when the Worker thows an exception. The "this" object is set to the worker object. | |
| onmessage | Function | Callback function to receive incoming messages. This is invoked when postMessage is called in another Worker. The "this" object is set to the worker object. This is invoked as: function (event) { }. |
Worker Class Methods
| Qualifiers | Method |
|---|---|
| static | exit(): Void |
| Exit the worker. | |
| static | fork(): Worker |
| Create a new worker by cloning the current interpreter. | |
| static | join(workers: Object = null, timeout: Number = -1): Boolean |
| Wait for Workers to exit. | |
| static | lookup(name: String): Worker |
| Lookup a Worker by name. |
Worker Instance Methods
| Qualifiers | Method |
|---|---|
| Worker(script: Path = null, options: Object = null) | |
| Create a new Worker instance. | |
| clone(deep: Boolean = true): Worker | |
| Clone the worker and underlying interpreter. | |
| eval(script: String, timeout: Number = -1): Object | |
| Load the script. | |
| load(script: Path, timeout: Number = 0): Void | |
| Load and run a script in a dedicated worker thread. | |
| postMessage(data: Object, ports: Array = null): Void | |
| Post a message to the Worker's parent. | |
| preload(path: Path): Object | |
| Preload the specified script or module file to initialize the worker. | |
| terminate(): Void | |
| Terminate the worker. | |
| waitForMessage(timeout: Number = -1): Boolean | |
| Wait for receipt of a message. |
Method Detail
- Description
- Create a new Worker instance. This call returns an outside worker object for using in the calling interpreter. Inside the worker interpreter, a corresponding "inside" worker object is created that is paired to the outside worker.
- Parameters
script: Path Optional path to a script or module to execute. If supplied, then a new Worker instance will invoke load() to execute the script. [default: null] options: Object Options hash. [default: null]
- Options
search Search path. name Name of the Worker instance.
- Specified
- WebWorker and ejs
- Description
- Clone the worker and underlying interpreter.
- Parameters
deep: Boolean Ignored. [default: true]
- Specified
- ejscript-2.5
- Description
- Load the script. The literal script is compiled as a JavaScript program and loaded and run. This is similar to the global eval() command but the script is run in its own interpreter and does not share any data the the invoking interpreter. The result is serialized in the worker and then deserialized (using JSON) in the current interpreter. The call returns undefined if the timeout expires.
- Parameters
script: String Literal JavaScript program string. timeout: Number If the timeout is non-zero, this call blocks and will return the value of the last expression in the script. Otherwise, this call will not block and join() can be used to wait for completion. Set the timeout to -1 to block until the script completes. The default is -1. [default: -1]
- Returns
- The value of the last expression evaluated in the script. Returns undefined if the timeout expires before the script completes.
- Throws
- Specified
- ejscript-2.5
static exit(): Void
- Description
- Exit the worker.
- Specified
- ejscript-2.5
static fork(): Worker
- Description
- Create a new worker by cloning the current interpreter.
- Specified
- ejscript-2.5
- Description
- Wait for Workers to exit.
- Parameters
workers: Object Set of Workers to wait for. Can be a single Worker object or an array of Workers. If null or if the array is empty, then all workers are waited for. [default: null] timeout: Number Timeout to wait in milliseconds. The value -1 disables the timeout. [default: -1]
- Specified
- ejs `
- Description
- Load and run a script in a dedicated worker thread.
- Parameters
script: Path Filename of a script or module to load and run. timeout: Number If the timeout is non-zero, this call blocks and will return the value of the last expression in the script. Otherwise, this call will not block and join() can be used to wait for completion. Set the timeout to -1 to block until the script completes. The default is to not block. [default: 0]
- Specified
- ejscript-2.5
- Description
- Preload the specified script or module file to initialize the worker. This will run a script using the current thread. This call will load the script/module and initialize and run global code. The call will block until all global code has completed and the script/module is initialized. To run a worker using its own thread, use load() or Worker(script) instead.
- Parameters
path: Path Filename path for the module or script to load. This should include the file extension.
- Returns
- The value of the last expression in the script or module.
- Throws
- Specified
- ejscript-2.5
terminate(): Void
- Description
- Terminate the worker.
- Description
- Wait for receipt of a message.
- Parameters
timeout: Number Timeout to wait in milliseconds. [default: -1]
- Returns
- True if a message was received.
- Stability
- Prototype.