AWS4 Signature generation using LoadRunner

AWS4 Signature Generation steps

Steps for AWS4 signature generation is documented in detail here https://docs.aws.amazon.com/general/latest/gr/sigv4_signing.html 

Here are the 4 steps at high level

Step1: Create a Canonical Request for Signature Version 4
Step2 : Create a String to Sign for Signature Version 4
Step 3: Calculate the Signature for AWS Signature Version 4
Step 4: Add the Signing Information to the Request

AWS4 Signature Generation using LoadRunner

AWS4 signature is generated using Javascript .

AWS4 Signature Generation steps

Steps for AWS4 signature generation is documented in detail here https://docs.aws.amazon.com/general/latest/gr/sigv4_signing.html 

Here are the 4 steps at high level

Step1: Create a Canonical Request for Signature Version 4
Step2 : Create a String to Sign for Signature Version 4
Step 3: Calculate the Signature for AWS Signature Version 4
Step 4: Add the Signing Information to the Request

AWS4 Signature Generation using LoadRunner

AWS4 signature is generated using Javascript .

2. In awsSignature.js we have 4 functions defined.

  Function1: Generates required date and time stamps using below javascript function

     function unixts(){
              var now = new Date();
              var isoString = now.toISOString();
                  var newIsoString = now.toISOString().slice(0,19).replace(/-/g,"").replace(/:/g,"");
                  var finIsoString = newIsoString.concat("Z");
                  var DateStamp = now.toISOString().slice(0,10).replace(/-/g,"");
                  var values=[DateStamp,finIsoString];
                  return values;
              }

           Function2: Generates canonical request                                  

Function3: Generates string to sign

Function4: Generates AWS signature and returns  to the main C script along with other required values .

Note: Also the below files are required for signature generation. These can be pulled from node.js libraries

3. Since values are returned as a string, they have to be sliced and the leading and trailing characters, spaces have to be removed.

Slicing is done using strtok and characters are removed using custom c function. Please refer the script for details.

4. Enable the below from RTS > Preferences in vugen, to execute the javascript code.