By default, event receivers process incoming messages in the XML, JSON, Text, Map (Key-value pairs), and WSO2Event formats. If the incoming events adhere to a default format/wiki/spaces/TESB/pages/32604416, select the supported default format for Message Format property under Mapping Configuration when creating event receivers.
However, if the incoming events do not adhere to a default format, when creating event receivers select the supported format for Message Format, click the Advanced section, and provide input mappings to convert the message to a canonical format for the server to understand the message and process it.
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