[MacPorts] #56975: livecheck broken in GitHub PortGroup

[MacPorts]

#56975: livecheck broken in GitHub PortGroup
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  Reporter:  l2dy    |      Owner:  (none)
      Type:  defect  |     Status:  new
  Priority:  Normal  |  Milestone:
 Component:  ports   |    Version:
Resolution:          |   Keywords:
      Port:          |
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Comment (by raimue):

 We cannot add the header to all requests through libcurl, as web servers
 might no longer send us some files. For example, if we want to download a
 `.tar.gz` but only accept `text/html` as content type, the server might
 reject our request.

 Probably we should have a parameter to allow passing arbitrary headers
 such as this "Accept:" into CurlFetchCmd from Tcl. Then it could only be
 used in the livecheck code.

 It gets harder to find the right regex if the content is different from
 what is served to a browser, so I think we should change this in base. The
 quickfix is of course to adapt the regex.

-- 
Ticket URL: <https://trac.macports.org/ticket/56975#comment:4>
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