Reset request body on retry

[embano1]

Fixes a bug where requests with a body (event) are not always retried due to the underlying net/http throwing *url.Error because of body and content-length mismatch (body is empty and not reset upon retry). See #773 for details.

The tests did not catch this as they were not doing behaving as a real HTTP server (just mocking RoundTripper) and also not carrying an event body (which would not trigger this behavior).

• Changed retry tests to use a network connection and HTTP (test) server
• Reset body (if not nil) during retries
• Set GetBody func only if it is not already set (the sdk already does this currently)

Closes: #773
Signed-off-by: Michael Gasch mgasch@vmware.com

[embano1]

Linter workflow seems broken.

Running locally only throws a small (existing) nit:

golangci-lint run
protocol/http/result_test.go:95:5: S1038: should use t.Errorf(...) instead of t.Error(fmt.Sprintf(...)) (gosimple)
                                t.Error(fmt.Sprintf("%v, expected result to be IsUndelivered == %t, got %t", tc.name, tc.want, got))

[n3wscott]

Thank you so much @embano1 !! Both for the detailed bug report and the follow-up fix. I will cherry-pick this into the current release as a bug fix and we will get this out. 🙏 🙏 🙏