Detect Content-Type of stdin via file util / "magic" heuristics

[jbyler]

When setting the body of a request via piped input (stdin), it would be nice to still auto-detect the Content-Type, using pymagic or python-magic or similar.

[jkbrzt]

I'd love to see this feature in HTTPie but the problem is the additional dependencies.

In addition to introducing dependency on python-magic (which seems to be the better one), there are further dependencies that python-magic needs.

[Almad]

Hi! Revisiting the issue after a while, some thoughts:

• Needs more thinking as we currently auto-supply json/formencode
• It is problematic with streaming as the mentioned libraries need some minimal amount of data to be able to decide
• We are conservative about adding dependencies
  • Since it uses libmagic, cross platform installation would get more complicated
  • It is a thin wrapper, most of the heavy work is done by the underlying C library which is complicated to compile/distribute

The feature is something we'd love to have, but it needs a reliable cross-platform solution, ideally in Python. Also needs further thinking into how it would affect the rest of the HTTPie.