Sign the request

2021-06-21 10:08

The following figure illustrates a sample API request. The content enclosed by the two curly braces (inclusive) is what needs to be signed to create the RSA signature. And the generated signature is put in the signature parameter.

Perform the following steps to sign the message:

Extract the content to be signed. For example:

copy
{
    "head":{
         "version":"2.0.0",
        "function":"alipay.intl.acquiring.agreement.payCancel",
        "clientId":"211xxxxxxxxxxxxxxx044",
        "reqTime":"2001-07-04T12:08:56+05:30",
        "reqMsgId":"1234567asdfasdf1123fda",
        "reserve":"{}"
           },
    "body":{
        "merchantId":"218xxxxxxxxxxxxxxx023",
        "acquirementId":"2015xxxxxxxxxxxxxxxxxxxxx747"
           }
 }

Hash the JSON content by using the SHA1 with the RSA algorithm. Then use the client's RSA private key to sign the value to obtain the signature. To achieve a better security level, the length of the RSA key/pairs must be 2048 bits. The following sample illustrates a raw signature:

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sXSGdA4tR4B0wnF6Nr8ShpfNMtHISWuzLpdKoNWskIgCcspMVFFzgkez4BrmtYXkMqZh1tyz/8sNNU3F2VTu0fOx+ZP4CnmVjNu8bciu4hTtnytA3Y1GZ/yXAUD+mVYGXeyDO3fHrqDdI7k3xV/Q8FCOd0culTsN6RRMxMZq+oqR2x+EjOXVofp7BZJwhQE8Us4Al573FQz5EHDvCLx35lq2hoMhXLCVLVDBHcpCgotuY4mg91MXh/qqcFGY/hQKhGdWAbZ9tcp2Q5s2ESh37rqxnOwZrrepK8NC6vMBPUiSPxQefpev2nG0JzAHOjRPbBXYw1XBS6RBYKAmufZZiQ==

Base64-encode the signature. A sample result is listed below:

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c1hTR2RBNHRSNEIwd25GNk5yOFNocGZOTXRISVNXdXpMcGRLb05Xc2tJZ0Njc3BNVkZGemdrZXo0QnJtdFlYa01xWmgxdHl6LzhzTk5VM0YyVlR1MGZPeCtaUDRDbm1Wak51OGJjaXU0aFR0bnl0QTNZMUdaL3lYQVVEK21WWUdYZXlETzNmSHJxRGRJN2szeFYvUThGQ09kMGN1bFRzTjZSUk14TVpxK29xUjJ4K0VqT1hWb2ZwN0JaSndoUUU4VXM0QWw1NzNGUXo1RUhEdkNMeDM1bHEyaG9NaFhMQ1ZMVkRCSGNwQ2dvdHVZNG1nOTFNWGgvcXFjRkdZL2hRS2hHZFdBYlo5dGNwMlE1czJFU2gzN3JxeG5Pd1pycmVwSzhOQzZ2TUJQVWlTUHhRZWZwZXYybkcwSnpBSE9qUlBiQlhZdzFYQlM2UkJZS0FtdWZaWmlRPT0=

Use the obtained string as the value of the Signature parameter. The following sample shows a whole API request:

copy
{
"request":{
     "head":{
         "version":"2.0.0",
         "function":"alipay.intl.acquiring.agreement.payCancel",
         "clientId":"211xxxxxxxxxxxxxxx044",
         "reqTime":"2001-07-04T12:08:56+05:30",
         "reqMsgId":"1234567asdfasdf1123fda",
         "reserve":"{}"
            },
     "body":{
         "merchantId":"218xxxxxxxxxxxxxxx023",
         "acquirementId":"2015xxxxxxxxxxxxxxxxxxxxx747"
            }
},
"signature":"c1hTR2RBNHRSNEIwd25GNk5yOFNocGZOTXRISVNXdXpMcGRLb05Xc2tJZ0Njc3BNVkZGemdrZXo0QnJtdFlYa01xWmgxdHl6LzhzTk5VM0YyVlR1MGZPeCtaUDRDbm1Wak51OGJjaXU0aFR0bnl0QTNZMUdaL3lYQVVEK21WWUdYZXlETzNmSHJxRGRJN2szeFYvUThGQ09kMGN1bFRzTjZSUk14TVpxK29xUjJ4K0VqT1hWb2ZwN0JaSndoUUU4VXM0QWw1NzNGUXo1RUhEdkNMeDM1bHEyaG9NaFhMQ1ZMVkRCSGNwQ2dvdHVZNG1nOTFNWGgvcXFjRkdZL2hRS2hHZFdBYlo5dGNwMlE1czJFU2gzN3JxeG5Pd1pycmVwSzhOQzZ2TUJQVWlTUHhRZWZwZXYybkcwSnpBSE9qUlBiQlhZdzFYQlM2UkJZS0FtdWZaWmlRPT0="
}