[tor-bugs] #7822 [Pluggable transport]: Create an ezpt pluggable transports wrapper

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#7822: Create an ezpt pluggable transports wrapper
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     Reporter:  dcf                  |      Owner:  asn
         Type:  project              |     Status:  needs_review
     Priority:  normal               |  Milestone:
    Component:  Pluggable transport  |    Version:
   Resolution:                       |   Keywords:  easy
Actual Points:                       |  Parent ID:
       Points:                       |
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Comment (by asn):

 OK. I did a code review.

 The code looks OK and I don't think it screws up with obfsproxy internals
 that much.

 I think I'd be up for merging this now, and potentially remove it in the
 future if we make a dedicated ezpt program. David what do you think?

 Some notes:

 - Would be nice if we had unittests for the file parsing methods. They are
 not trivial. See `obfsproxy/test/transports/` for transport-specific unit
 tests.

 - Function docs would be helpful. e.g. in `checkExit`,
 `get_all_transports`, `parse`.

 - The `circuitDestroyed` functionality is quite complicated and
 undocumented. Does this recursion need to happen? Can it be made more
 cleanly?

 - We need to document the EZPT_SPEC env variable. Maybe even rename it to
 something more explicit: `OBFSPROXY_EZPT_FILE` or something.

 - I'm not sure if I like ezpt transports clobbering the transport list of
 obfpsroxy. However, it's true that ezpt transports are pluggable
 transports too, so they should be there. We should at least disable
 `ezpt_id` and maybe think of some smarter recipes for the default ezpt
 transports.

 Also see branch `ezpt_review` in
 `https://git.torproject.org/user/asn/obfsproxy.git` for some additional
 tweaks and changes.

 Also also, can you rebase this branch so that the ezpt.py changes are all
 in a single squashed commit, and all the other obfsproxy changes are in
 logical individual commits? Feel free to also squash my initial commits
 even if it loses authorship information.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7822#comment:13>
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