Message type: E = Error
Message class:  ESH_ESAAS_MSG - Search as a Service (ESaaS) 
Message number: 028
Message text: Provide a collection Id (service 'metadata', http method POST)
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The SAP error message ESH_ESAAS_MSG028 typically indicates that a required parameter, specifically a collection ID, is missing in the request to the service. This error is related to the Enterprise Search (ES) functionality in SAP, particularly when interacting with the metadata service.
Cause: The error occurs when a POST request is made to the metadata service without providing a necessary collection ID. The collection ID is essential for the service to identify which collection of data it should operate on. This can happen due to: Missing Parameter: The request does not include the collectionId parameter. Incorrect Request Format: The request may not be formatted correctly, leading to the omission of required parameters.
Configuration Issues: There may be issues with the configuration of the service or the collections themselves.
Solution: To resolve this error, you can take the following steps: Check the Request: Ensure that the POST request to the metadata service includes the collectionId parameter. The request should
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