Set Request.GetBody in doRequest

[vincent-stytch]

I was running into an issue periodically:

Post "https://api.postmarkapp.com/email": http2: Transport: cannot retry err [http2: Transport received Server's graceful shutdown GOAWAY] after Request.Body was written; define Request.GetBody to avoid this error

when trying to send an email through this library.

Based on research (golang/go#62453, https://github.com/stripe/stripe-go/pull/711/files, https://ragoragino.dev/blog/softwareengineering/2022-02-05-goaway-test/index.html) it looks like Golang attempts a retry when receiving GOAWAY from a server. [https://sourcegraph.com/github.com/golang/net/-/commit/cffdcf672aee934982473246bc7e9a8ba446aa9b?visible=2](Go code here)

But, this means that we need to define a GetBody function in the request to allow the http2 package to retry. Since the payload we have here is static, we can set it equal to the Body.

I tested this by patching my dependency with this new version, and my emails still send, so I think this at least won't break anything.

[mergify]

Welcome to our open-source project! 💘

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 96.75%. Comparing base (6b50666) to head (92fba74).

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Additional details and impacted files

@@            Coverage Diff             @@
##           master      #58      +/-   ##
==========================================
- Coverage   97.10%   96.75%   -0.36%     
==========================================
  Files          13       13              
  Lines         552      554       +2     
==========================================
  Hits          536      536              
- Misses          9       10       +1     
- Partials        7        8       +1     

Flag	Coverage Δ
unittests	96.75% <0.00%> (-0.36%)	⬇️

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Files	Coverage Δ
postmark.go	72.72% <0.00%> (-3.47%)	⬇️

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[mrz1836]

LGTM

[vincent-stytch]

@mrz1836 just wondering what your release process is like? I see the last release v.1.6.4 was on Feb 28 2024 but I was wondering if it would be possible to add a new release? Thanks so much!

[mrz1836]

@vincent-stytch usually same day on the release :P