This implements a new debug/trace infrastructure based on a slightly
hacked up logger. Instead of the traditional "if debug { ... }" I've
rewritten the logger to have no-op Debugln and Debugf, unless debugging
has been enabled for a given "facility". The "facility" is just a
string, typically a package name.
This will be slightly slower than before; but not that much as it's
mostly a function call that returns immediately. For the cases where it
matters (the Debugln takes a hex.Dump() of something for example, and
it's not in a very occasional "if err != nil" branch) there is an
l.ShouldDebug(facility) that is fast enough to be used like the old "if
debug".
The point of all this is that we can now toggle debugging for the
various packages on and off at runtime. There's a new method
/rest/system/debug that can be POSTed a set of facilities to enable and
disable debug for, or GET from to get a list of facilities with
descriptions and their current debug status.
Similarly a /rest/system/log?since=... can grab the latest log entries,
up to 250 of them (hardcoded constant in main.go) plus the initial few.
Not implemented in this commit (but planned) is a simple debug GUI
available on /debug that shows the current log in an easily pasteable
format and has checkboxes to enable the various debug facilities.
The debug instructions to a user then becomes "visit this URL, check
these boxes, reproduce your problem, copy and paste the log". The actual
log viewer on the hypothetical /debug URL can poll regularly for new log
entries and this bypass the 250 line limit.
The existing STTRACE=foo variable is still obeyed and just sets the
start state of the system.
Not necessarily the easiest way to fix just this bug, but the root cause
was using the (at that point uninitialized) cfg variable, so it seemed
sensible to just get rid of it to avoid that kind of crap.
An error on opening .stignore will satisfy os.IsNotExist() and not be
reported. Other errors will be reported and stop the folder, including
is-not-exist errors from #include as these are passed through fmt.Errorf.
Also fixes minor issue where we would not print cause of folder stopping
to the log.
Also fixes minor issue with capitalization of errors.
The XDR encoder doesn't understart slices of strings very well. It can
encode and decode them, but there's no way to set limits on the length
of the strings themselves (only on the length of the slice), and the
generated diagrams are incorrect. This trivially works around this,
while also documenting what the string actually is (a URL).
This should resolve the spurious ping timeouts we've had on low powered
boxes. Those errors are the result of us requiring a timely Pong
response to our Pings. However this is unnecessarily strict - as long as
we've received *anything* recently, we know the other peer is alive. So
the new mechanism removes the Pong message entirely and separates the
ping check into two routines:
- One that makes sure to send ping periodically, if nothing else has
been sent. This guarantees a message sent every 45-90 seconds.
- One that checks how long it was since we last received a message. If
it's longer than 300 seconds, we trigger an ErrTimeout.
So we're guaranteed to detect a connection failure in 300 + 300/2
seconds (due to how often the check runs) and we may detect it much
sooner if we get an actual error on the ping write (a connection reset
or so).
This is more sluggish than before but I think that's an OK price to pay
for making it actually work out of the box.
This removes the configurability of it, as the timeout on one side is
dependent on the send interval on the other side. Do we still need it
configurable?
This makes it so we can initialize the relay management and then give
that to the connection management, instead of the other way around.
This is important to me in the discovery revamp I'm doing, as otherwise
I get a circular dependency when constructing stuff, with relaying
depending on connection, connection depending on discovery, and
discovery depending on relaying.
With this fixed, discovery will depend on relaying, and connection will
depend on both discovery and relaying.
Instead, make sure we do the check as part of CheckFolderHealth before
pulling, and individually per file to try to not run out of space at
that stage.
(The latter is far from fool proof as we may pull lots of stuff in
parallell, but it's worth a try.)
This makes it possible to run multiple instances on the same box, all
receiving local discovery packets. Tested on Mac, Windows, supposed to
work on at least Linux too. For Windows, there may be issues with XP and
earlier, but meh...
Either Angular or the browser sometimes returns cached repsonse header,
causing a flap between requests that return the new version and requests
that return the old one. Here, instead, we trust the actual data
returned by the uncached /rest/system/version call.
Jakob Borg