HMAC Signature mismatch

[cm devops]

Hi,

I'm using this script to validate the webhook signatures.
https://confluence.atlassian.com/bbkb/bitbucket-cloud-python-sample-code-to-verify-webhook-signature-1346243949.html-1346243949.html 

When there is a colon : in the commit message (i.e., Test Commit : #1), script returns a mismatch in signature. Any suggestions to overcome this scenario?

[Suhas Sundararaju]

Hi @cm devops 

The issue arises because the script removes whitespaces after the colon, causing the problem. To address this, I've modified the script to convert the payload data back to a single-line JSON string with separators ',' and ':', and to pretty print the original payload with payload_data, indent=2). This adjustment should resolve the issue.

Furthermore, I want to highlight that there may be a discrepancy in how Bitbucket Cloud calculates HMAC signature compared to how the script calculates it. You may need to modify the script accordingly. The ultimate goal is to convert JSON to a single line while removing whitespaces.

You can find the modified script at the following link: https://confluence.atlassian.com/display/BBKB/Bitbucket+Cloud+-+Python+sample+code+to+verify+webhook+signature

I hope this helps.

[cm devops]

Thanks @Suhas Sundararaju

It works!