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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

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 debugger to attach to a tab, instrument its network interaction, debug JavaScript, mutate page's DOM and CSS, etc.

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(, integer tabId, function callback)

Attaches debugger to the tab with given id.

Parameters

tabId
( Type array of integer )
The id of the tab 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.
callback
( optional Type array of function )
If an error occurs while attaching to the tab, 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() {...};

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(, integer tabId, function callback)

Detaches debugger from a tab with given id.

Parameters

tabId
( Type array of integer )
The id of the tab 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 )
If an error occurs while detaching from the tab, 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() {...};

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.

sendRequest

void chrome.experimental.debugger.sendRequest(, integer tabId, string method, object params, function callback)

Sends given request to the debugger.

Parameters

tabId
( Type array of integer )
The id of the tab to which you want to send debugging request.
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(integer tabId) {...});

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

tabId
( Type array of integer )
The id of the tab 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(integer tabId, string method, object params) {...});

Fired whenever debugger issues instrumentation event.

Listener parameters

tabId
( Type array of integer )
The id of the tab that generated debug 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