📞 Callback Description

📢 OpenIM offers powerful callback functionalities. When a specific event happens before or after a process, OpenIMServer proactively sends an HTTP/HTTPS request to the APP’s business server. This allows the APP’s business server to intervene in the subsequent processing of that event or to perform data synchronization based on the callback.

📑 Callback Classification

Callbacks are divided into two main types based on the timing of their processing:

•   🚫 **Callbacks Before the Event Occurs**: These “before” type callbacks allow the APP’s business server to intervene in the event handling process. For example, you can implement sensitive word filtering for messages. OpenIMServer determines subsequent steps based on the callback response.
•   📤 **Notifications After the Event Occurs**: These “after” type callbacks are mainly used to notify the APP’s business server for data synchronization. For example, when a user joins a group. In this case, OpenIMServer ignores the callback’s return values and error codes.

⚙️ Configuration Description

url: http://127.0.0.1:10006/callbackExample
beforeSendSingleMsg:
  enable: false
  timeout: 5
  failedContinue: true

•   url: The APP business server callback address, supports HTTP/HTTPS
•   enable: Whether to enable the callback, true for enable
•   timeout: Response timeout in seconds
•   failedContinue: Whether to continue the process if the callback times out or if the API fails. Generally effective for before type callbacks. true means to continue execution.

🔄 Callback Protocol

OpenIMServer uses a third-party callback mechanism based on HTTP/HTTPS protocol. When initiating a callback request, OpenIMServer sends a POST request to notify the APP’s business server. The specifics of these requests are directly included in the request body.

Sample Request URL

{WEBHOOK_ADDRESS}/callbackCommand?contenttype=json

Request Parameter Description

Parameter	Description
{WEBHOOK_ADDRESS}	The url field in webhooks.yml, domain or hostname, for example: http://127.0.0.1:10006/callbackExample
callbackCommand	The callback command, refer to each callback method’s description for details
contenttype	The request input type, json

Header

Header Name	Example Value	Required	Type	Description
operationID	123456	Yes	string	Used for global link tracking, recommended to use timestamps, unique in each request