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paramName
( optional enumerated Type array of paramType )
Undocumented.
Description of this parameter from the json schema.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
Parameters
  1. Properties
    1. propertyName
  2. Methods
    1. methodName
  3. Events
    1. eventName
  4. Types
    1. id

Google Chrome Extensions (Labs)

chrome.experimental.debugger

For information on how to use experimental APIs, see the chrome.experimental.* APIs page.

Notes

Debugger API serves as an alternate transport for Chrome's remote debugging protocol. Use chrome.experimental.debugger to attach to one or more tabs to instrument network interaction, debug JavaScript, mutate the DOM and CSS, etc. Use the Debuggee tabId to target tabs with sendCommand and route events by tabId from onEvent callbacks.

As of today, attaching to the tab by means of the debugger API and using embedded Chrome DevTools with that tab are mutually exclusive. If user invokes Chrome DevTools while extension is attached to the tab, debugging session is terminated. Extension can re-establish it later.

Manifest

You must declare the "debugger" permission in your extension's manifest to use this API. The debugger API is currently experimental, so you must declare the "experimental" permission to use it as well. 

{
  "name": "My extension",
  ...
  "permissions": [
    "debugger",
    "experimental"
  ],
  ...
}

Examples

You can find samples of this API in Samples.

API reference: chrome.experimental.debugger

Methods

attach

void chrome.experimental.debugger.attach(, Debuggee target, string requiredVersion, function callback)

Attaches debugger to the given target.

Parameters

target
( Debuggee array of paramType )
Debugging target to which you want to attach.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
requiredVersion
( Type array of string )
Required debugging protocol version ("0.1"). One can only attach to the debuggee with matching major version and greater or equal minor version. List of the protocol versions can be obtained here.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
callback
( optional Type array of function )
Called once the attach operation succeeds or fails. Callback receives no arguments. If the attach fails, chrome.extension.lastError will be set to the error message.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function() {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

detach

void chrome.experimental.debugger.detach(, Debuggee target, function callback)

Detaches debugger from the given target.

Parameters

target
( Debuggee array of paramType )
Debugging target from which you want to detach.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
callback
( optional Type array of function )
Called once the detach operation succeeds or fails. Callback receives no arguments. If the detach fails, chrome.extension.lastError will be set to the error message.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function() {...};

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

sendCommand

void chrome.experimental.debugger.sendCommand(, Debuggee target, string method, object params, function callback)

Sends given command to the debugging target.

Parameters

target
( Debuggee array of paramType )
Debugging target to which you want to send the command.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
method
( Type array of string )
Method name. Should be one of the methods defined by the remote debugging protocol.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
params
( optional Type array of object )
JSON object with request parameters. This object must conform to the remote debugging params scheme for given method.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
callback
( optional Type array of function )
Response body. If an error occurs while posting the message, the callback will be called with no arguments and chrome.extension.lastError will be set to the error message.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Returns

Callback function

The callback parameter should specify a function that looks like this:

If you specify the callback parameter, it should specify a function that looks like this: 

function(object result) {...};
result
( optional Type array of object )
JSON object with the response. Structure of the response varies depending on the method and is defined by the remote debugging protocol.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

This function was added in version . If you require this function, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Events

onDetach

chrome.experimental.debugger.onDetach.addListener(function(Debuggee source) {...});

Fired when browser terminates debugging session for the tab. This happens when either the tab is being closed or Chrome DevTools is being invoked for the attached tab.

Listener parameters

source
( Debuggee array of paramType )
The debuggee that was detached.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Extra parameters to addListener

Listener returns

onEvent

chrome.experimental.debugger.onEvent.addListener(function(Debuggee source, string method, object params) {...});

Fired whenever debugging target issues instrumentation event.

Listener parameters

source
( Debuggee array of paramType )
The debuggee that generated this event.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
method
( Type array of string )
Method name. Should be one of the notifications defined by the remote debugging protocol.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
params
( optional Type array of object )
JSON object with the response. Structure of the response varies depending on the method and is defined by the remote debugging protocol.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.

Extra parameters to addListener

Listener returns

Types

Debuggee

paramName
( Type array of object )
Debuggee identifier.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.
tabId
( Type array of integer )
The id of the tab which you intend to debug.
This parameter was added in version . You must omit this parameter in earlier versions, and you may omit it in any version. If you require this parameter, the manifest key minimum_chrome_version can ensure that your extension won't be run in an earlier browser version.