I am using Microsoft flow HTTP request tigger and i am calling it from SharePoint.
For you first question, if you want to accept parameters through your HTTP endpoint URL, you could customize your trigger's relative path. I have made a test on my side and please take a try with the following workaround:
The flow works successfully as below:
More details about accepting parameters through your HTTP endpoint URL, please check the following article:
For your second question, the HTTP Request trigger use a Shared Access Signature (SAS) key in the query parameters that are used for authentication. More details about the Shared Access Signature (SAS) key authentication, please check the following article:
For your third question, if you want to make your URL more secure, you could consider make more advanced configuration through API Management. More details about configuring HTTP endpoints further, please check the following article:
I appreciate the additional links you provided regarding advanced security on Flows. I recognize that Flows are implemented using Azure Logic Apps behind the scenes, and that the links you provided related to Logic Apps. However, I am unclear how the configuration for Logic Apps security can be used to secure the endpoint for a Flow. The documentation requires the ability to select a Logic App that you want to configure. However, the Flow is not visible in Azure API Management, so I don't understand how the links you provided can be used to provide further security for the Flow. Do you have any additional information or insight that you could provide?
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