Urlscm: add support for custom headers

[rhubert]

Some servers need additional informations provided by custom headers.
Add a headers attribute where the user can set these custom headers.

[rhubert]

I think we do not need the headers to the digest? At least I hope the result did not depend on any request header...

[codecov]

Codecov Report

❌ Patch coverage is 88.88889% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 88.97%. Comparing base (f958833) to head (d594037).
⚠️ Report is 5 commits behind head on master.

Files with missing lines	Patch %	Lines
pym/bob/input.py	85.71%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #655   +/-   ##
=======================================
  Coverage   88.97%   88.97%           
=======================================
  Files          50       50           
  Lines       16116    16124    +8     
=======================================
+ Hits        14339    14347    +8     
  Misses       1777     1777           

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[jkloetzke]

I think we should apply the headers in _uploadtoo.

[rhubert]

I think we should apply the headers in _uploadtoo.

🤔 AFAICS _upload is used for mirrors only? And for mirrors different headers might be required?

My use-case is to send a authorization header. I don't want to send this to any mirror, so I think headers should be used only for the scm where they are defined (which is not the case ATM).

OTOH mirrors (up&download) might also need some custom headers, but in this case we'd need to extend the mirror keyword?

[jkloetzke]

🤔 AFAICS _upload is used for mirrors only? And for mirrors different headers might be required?

You're completely right. Any headers for the upload need to come from the mirror definition.

I think we do not need the headers to the digest? At least I hope the result did not depend on any request header...

I agree. If there is a digestSHA... property, the result is fixed. Otherwise, Bob will redo the download each time anyway. So in the first case the headers must not have any impact and in the latter case it won't matter.

[jkloetzke]

Thanks.