This fixes#145. I thought it would add a roundtrip, but it turns out that
websockets were already adding the same delay, so I can't avoid it without
switching from websockets to raw TCP. Closes#145.
This renames all the existing API methods, to use a consistent
"d=get_XYZ()" (for Deferred mode) or "dg.wormhole_got_XYZ()" (for Delegated
mode). It updates cmd_send/cmd_receive/cmd_ssh to use the new API.
Since we now have get_welcome(), apps handle the Welcome message with a
Deferred callback instead of registering a "welcome handler". This lets us
make sure we've finished printing any server message-of-the-day or "you
should update your client" message to stdout before using stdio to ask for
the wormhole code. (Previously, the code-input prompt was overwritten by the
server message, and it was ugly). refs #145. This approach adds an extra
roundtrip to the receiver, but we can fix that (see #145 for details).
Because of that change, the server-is-being-slow message is printed at a
slightly different time, so those tests needed some extra work to exercise it
properly.
The code in util.py can tolerate a missing os.statvfs, but the code which
tests that code's ability to tolerate a missing os.statvfs was itself unable
to tolerate a missing os.statvfs. Sigh.
Apparently there's an intermittent condition in tests that follows this path.
We used to ignore unrecognized states, but to improve test coverage I added a
clause to catch them, and now that clause is happening where I didn't expect
it.
This fixes the case where "wormhole send" would wait forever (upon network
error) instead of terminating with a useful error message.
Testing this will have to wait until we land the branch that abandons the
wormhole if the first connection fails, since that's the easiest way to
provoke a network error before when_code() has fired.
I think we're better off without this: the CLI commands propagate the Failure
up to their callers (rather than eating it silently), the callers are using
task.react (which reacts to Failures by exiting with rc!=0), so nothing
should get lost. And doing an extra log.err() just creates more cleanup work
for test cases to flush, and makes the CLI commands double-print the any
errors (maybe task.react also points logging at stderr?).
