The strings string_sigture and kdate are to be signed; and then based on the result obtained on hmacsha256 (kdate, string_sigture), the result is base64 encoded to obtain the Sigture; and then the data is integrated into HEADER and placed in http_client, and then you can issue them.
HEADER name is Eop-Authorization. The ctyun-eop-ak Header=The header ranking when you construct the string to be signed. Signature= Calculated Sigture value.
For example, the header sequence of the string you want to sign is eop-date and host; then the value you add to the header is:
Eop-Authorization: {ctyun-eop-ak} Header=eop-date;host Signature=xad01/ada