Register an Event Handler BX24.callBind

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BX24.callBind(
            String event,
            String handler[,
                Integer auth_type[,
                    Function callback
                ]
            ]
        );

The BX24.callBind function registers an online event handler for the current application. The library calls event.bind on behalf of the user who opened the application.

The function can be called only from an application embedded in a Bitrix24 frame. If it is called before BX24.init, the library waits for initialization and retries the call, but synchronously returns false.

Registered handlers are removed after the application is deleted or updated. Register them again when installing each application version. Events start arriving only after installation is completed using BX24.installFinish.

Note

The function works only for a user with Bitrix24 administrator permissions. For other users, it synchronously returns false, sends no request, and does not call callback. This restriction is imposed by the library: event.bind allows a regular user to register online events with restrictions.

Method Parameters

Required parameters are marked with *

Name `type`	Description
event* `string`	Event name, for example, `ONAPPUNINSTALL`. The name is case-insensitive
handler* `string`	Event handler URL. It must be accessible to external requests from Bitrix24 servers
auth_type `integer`	Identifier of the user on whose behalf the event handler is authorized. A value of `0` means authorization on behalf of the user whose action triggered the event. This is the default value
callback `function`	Function that handles the method call result (detailed description)

Code Examples

How to Use Examples in Documentation

BX24.init(() => {
            BX24.callBind(
                'ONAPPUNINSTALL',
                'https://www.my-domain.com/handler/'
            );
        });

BX24.init(() => {
            BX24.callBind(
                'ONAPPUNINSTALL',
                'https://www.my-domain.com/handler/',
                15,
                (result) => {
                    if (result.error())
                    {
                        console.error(result.error());
                    }
                    else if (result.data() === true)
                    {
                        console.log('Handler registered');
                    }
                }
            );
        });

Response Handling

The callback function receives an ajaxResult object, the same as BX24.callMethod. The data() method returns response data, and error() returns the error.

true

Returned Data

Name `type`	Description
result `boolean`	Handler registration result. `true` means the handler was registered. `false` means the handler URL failed validation

Error Handling

{
            "status": 400,
            "ex": {
                "error": "ERROR_ARGUMENT",
                "error_description": "Argument 'EVENT' is null or empty",
                "argument": "EVENT"
            }
        }

The error code is available in result.error().ex.error, the message in result.error().ex.error_description, and the invalid parameter name in result.error().ex.argument. The HTTP status is returned by result.error().status and getStatus(). The toString() method returns a formatted string containing the code, message, and status.

Name `type`	Description
error `string`	String error code. It consists of digits, Latin letters, and underscores. It may arrive empty — in that case only `error_description` shows the reason
error_description `string`	Error message for the developer. Do not show it to the end user without processing

Possible Error Codes

Status	Code	Description	Meaning
`400`	`ERROR_ARGUMENT`	Argument 'EVENT' is null or empty	Event name was not passed
`400`	`ERROR_ARGUMENT`	Argument 'HANDLER' is null or empty	Handler URL was not passed
`400`	`ERROR_EVENT_NOT_FOUND`	Event not found	The specified event was not found
`400`	`ERROR_CORE`	Unable to set event handler	The handler could not be registered

Errors from event.bind about missing administrator permissions are not returned through this function because the request does not reach the server.

Responses with a 5xx status are not passed to callback. The library throws a Query error! exception from the asynchronous request handler, so a try/catch around the call does not catch it.

Statuses and System Error Codes

HTTP Status: 4xx, 5xx

The errors described below are returned by the REST API itself, not by the logic of a specific method. They can arrive in response to any method.

Status	Code Error Message	Description
`500`	`INTERNAL_SERVER_ERROR` Internal server error	An internal server error has occurred. Retry the call, and if the error persists, contact the server administrator or Bitrix24 technical support
`500`	`ERROR_UNEXPECTED_ANSWER` Server returned an unexpected response	The server returned an unexpected response. Retry the call, and if the error persists, contact the server administrator or Bitrix24 technical support
`503`	`QUERY_LIMIT_EXCEEDED` Too many requests	The request intensity limit has been exceeded
`429`	`OPERATION_TIME_LIMIT` Method is blocked due to operation time limit	The method is blocked because the request resource intensity limit has been exceeded. The block is lifted automatically once the accumulated execution time of the method no longer exceeds the limit
`401`	`NO_AUTH_FOUND` Wrong authorization data	The request contains no authorization data: neither an access token nor a webhook code was passed
`401`	`INVALID_REQUEST` Https required	Methods are called over the HTTPS protocol only
`401`	`OVERLOAD_LIMIT` REST API is blocked due to overload	The REST API is blocked due to overload. This is a manual individual block. To have it lifted, contact Bitrix24 technical support
`401`	`ACCESS_DENIED` REST is available only on commercial plans	REST API access is not active for this account. In Bitrix24 Cloud, check the current plan or trial status: Vibe+ plans include REST API access, while Essentials plans do not. A webhook receives a different error message — `REST is available only by subscription`
`401`	`INVALID_CREDENTIALS` Invalid request credentials	No active webhook with the specified user identifier and secret code was found
`404`	`ERROR_METHOD_NOT_FOUND` Method not found!	No method with this name was found. The name is misspelled, the method does not exist in the REST API, or it is unavailable without the required scope
`401`	`insufficient_scope` The request requires higher privileges than provided by the webhook token	The request requires broader permissions than the token has: for a webhook these are the permissions granted to it, for an application it is the scope. For an application, the error message ends with `provided by the access token`
`401`	`expired_token` The access token provided has expired	The access token has expired
`401`	`user_access_error` The user does not have access to the application	The application is installed, but the Bitrix24 administrator has granted access to it only to specific users
`403`	`PORTAL_DELETED` Portal was deleted	The public part of the site is closed. To open it on an on-premise installation, disable the "Temporary closure of the public part of the site" option. Path to the setting: Desktop > Settings > Product Settings > Module Settings > Main Module > Temporary closure of the public part of the site

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