[NitinKumar004]

Make entries in announce.webhook.headers replace the headers goreleaser
sets by default (Content-Type, User-Agent, and Authorization from the
auth env vars) instead of being appended next to them.

The custom headers loop used req.Header.Add. For a key goreleaser had
already set, that produced two values. User-Agent from headers was
silently ignored, because net/http only sends the first one. Content-Type
was sent twice. Authorization was sent twice whenever
BASIC_AUTH_HEADER_VALUE or BEARER_TOKEN_HEADER_VALUE was also set.

The fix is one line: Add becomes Set in that loop. That matches what
the other announcers do (discord, discourse, mattermost, telegram, ...).
I added two tests that look at r.Header.Values(...) on the server, so a
duplicate value fails them. The docs example used
User-Agent: "goreleaser", the same as the default, which is why this
went unnoticed. It now uses my-bot/1.0 and says that headers
overrides the defaults.

With this change, a configured Authorization header takes precedence
over the env vars. If you would rather the env vars win, I can flip the
order. Either way there will be only one value.

The three default headers are also set with Add. They could be Set
for consistency, but behaviour is the same since the request starts
empty, so I left them alone to keep the diff small.

Closes #7173

I used an AI assistant (Claude Code) to help find, fix and test this.
I've reviewed the changes and ran the tests myself.

[caarlos0]

thanks!

[NitinKumar004]

Thanks! The lint and test failures came from the old base: the lint error was in internal/pipe/ko/ko.go and the test failure was a Docker pull error in internal/pipe/blob, both already fixed on main. I rebased onto main, and build, tests and lint pass locally now. Pushing turned off auto-merge and the workflows need approval to run again, sorry about that.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.59%. Comparing base (61704ff) to head (97b2838).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7174      +/-   ##
==========================================
+ Coverage   91.58%   91.59%   +0.01%     
==========================================
  Files         192      192              
  Lines       15939    15939              
==========================================
+ Hits        14598    14600       +2     
+ Misses       1341     1339       -2     

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