Issue
Signature authentication fails when you call the HttpEndpoint operation.
Cause
Some HTTP server frameworks may format the HttpHeader parameter. As a result, signature authentication fails. For example, the x-mns-message-id parameter of the HttpEndpoint operation is converted into X-Mns-Message-Id after the formatting. The first letter of each word becomes an uppercase letter, as shown in the following figure.
Solution
Before you perform signature authentication, you can use a function or method to convert all parameters in HttpHeader to lowercase letters. If the issue persists, you can log on to Alibaba Cloud Community for free consultation. For more information, see Developer Community.