Fix decoding of publish command, publishing type is optional

[jbreich]

I have noticed that some tools are not providing the publishing type in the publish command. It is not explicitly optional in the specification but in practice it seems to be. And so by default I use the live value

[codecov]

Codecov Report

Patch coverage: 50.00% and project coverage change: +0.05 🎉

Comparison is base (73d0006) 62.55% compared to head (f76554c) 62.61%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #59      +/-   ##
==========================================
+ Coverage   62.55%   62.61%   +0.05%     
==========================================
  Files          36       36              
  Lines        1896     1899       +3     
==========================================
+ Hits         1186     1189       +3     
  Misses        569      569              
  Partials      141      141              

Flag	Coverage Δ
unittests	62.61% <50.00%> (+0.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
message/body_decoder.go	48.86% <50.00%> (+0.88%)	⬆️

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[yutopp]

Thank you for your PR! LGTM, so I'd like to proceed with the merge. By the way, would you be able to tell me the names of such tools that issue the publish command, just for reference?

Thank you.

[jbreich]

Hello,
Unfortunately I don't know exactly what is pushing that... from the information I have it is coming from an extron electronics (hardware equipment) through the restream SaaS platform. But I don't know exactly who is not providing the publishingType

[yutopp]

I see, thank you very much. It's intriguing, so I think I'd like to investigate based on the information you've provided.