This allows much of the read logic to be shared for other things,
especially for the new log driver proposed in
https://github.com/moby/moby/issues/33475
The only logic for reads in the json logger is around decoding log
messages, which gets passed into the log file object.
This also helps with implementing compression as it allows us to
simplify locking strategies.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 16f7cd674902b69b97692de2a83915a1a6be2cdb
Component: engine
Make the `*RotateFileWriter` specifically about writing
`logger.Message`'s, which is what it's used for.
This allows for future changes where the log writer can cache details
about log entries such as (e.g.) the timestamps included in a particular
log file, which can be used to optimize reads.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 52d82b4fbc9f0fe00f63e2df9a3d2a49d4095bda
Component: engine
Before this patch, a log reader is able to block all log writes
indefinitely (and other operations) by simply opening the log stream and
not consuming all the messages.
The reason for this is we protect the read stream from corruption by
ensuring there are no new writes while the log stream is consumed (and
caught up with the live entries).
We can get around this issue because log files are append only, so we
can limit reads to only the section of the file that was written to when
the log stream was first requested.
Now logs are only blocked until all files are opened, rather than
streamed to the client.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: e2209185ed1c959131d4068ec7fc93e194dc0802
Component: engine
This reduces allocs and bytes used per log entry significantly as well
as some improvement to time per log operation.
Each log driver, however, must put messages back in the pool once they
are finished with the message.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: 3f4fccb65f0ef286c9c4e0f01c4ae7bb09a6ad89
Component: engine
This change updates how we handle long lines of output from the
container. The previous logic used a bufio reader to read entire lines
of output from the container through an intermediate BytesPipe, and that
allowed the container to cause dockerd to consume an unconstrained
amount of memory as it attempted to collect a whole line of output, by
outputting data without newlines.
To avoid that, we replace the bufio reader with our own buffering scheme
that handles log lines up to 16k in length, breaking up anything longer
than that into multiple chunks. If we can dispense with noting this
detail properly at the end of output, we can switch from using
ReadBytes() to using ReadLine() instead. We add a field ("Partial") to
the log message structure to flag when we pass data to the log driver
that did not end with a newline.
The Line member of Message structures that we pass to log drivers is now
a slice into data which can be overwritten between calls to the log
driver's Log() method, so drivers which batch up Messages before
processing them need to take additional care: we add a function
(logger.CopyMessage()) that can be used to create a deep copy of a
Message structure, and modify the awslogs driver to use it.
We update the jsonfile log driver to append a "\n" to the data that it
logs to disk only when the Partial flag is false (it previously did so
unconditionally), to make its "logs" output correctly reproduce the data
as we received it.
Likewise, we modify the journald log driver to add a data field with
value CONTAINER_PARTIAL_MESSAGE=true to entries when the Partial flag is
true, and update its "logs" reader to refrain from appending a "\n" to
the data that it retrieves if it does not see this field/value pair (it
also previously did this unconditionally).
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com> (github: nalind)
Upstream-commit: 513ec73831269947d38a644c278ce3cac36783b2
Component: engine
inotify event is trigged immediately there's data written to disk.
But at the time that the inotify event is received, the json line might
not fully saved to disk. If the json decoder tries to decode in such
case, an io.UnexpectedEOF will be trigged.
We used to retry for several times to mitigate the io.UnexpectedEOF error.
But there are still flaky tests caused by the partial log entries.
The daemon knows exactly when there are new log entries emitted. We can
use the pubsub package to notify all the log readers instead of inotify.
Signed-off-by: Shijiang Wei <mountkin@gmail.com>
try to fix broken test. will squash once tests pass
Signed-off-by: Shijiang Wei <mountkin@gmail.com>
Upstream-commit: b1594c59f5e0d1ac898eacde8d91b1ba33c2b626
Component: engine
- Move time json marshaling to the jsonlog package: this is a docker
internal hack that we should not promote as a library.
- Move Timestamp encoding/decoding functions to the API types: This is
only used there. It could be a standalone library but I don't this
it's worth having a separated repo for this. It could introduce more
complexity than it solves.
Signed-off-by: David Calavera <david.calavera@gmail.com>
Upstream-commit: 27220ecc6b1eedf650ca9cf94965cb0dc2054efd
Component: engine
The json decoder starts to decode immediately an inotify event is
received.
But at the time the inotify event is trigged, the json log
entry might haven't been fully written to the disk.
In this case the decoder will return an "io.UnexpectedEOF" error, but
there is still data remaining in the decoder's buffer. And the data
should be passed to the decoder when the next inotify event is
triggered.
Signed-off-by: Shijiang Wei <mountkin@gmail.com>
Upstream-commit: e41eae8b42052d07432405cca113ffcf8cf49c06
Component: engine
this allows jsonfile logger to collect extra metadata from containers with
`--log-opt labels=label1,label2 --log-opt env=env1,env2`.
Extra attributes are saved into `attrs` attributes for each log data.
Signed-off-by: Daniel Dao <dqminh@cloudflare.com>
Upstream-commit: 0083f6e984894b4d3697c1ae63547c07eea697af
Component: engine
After tailing a file, if the number of lines requested is > the number
of lines in the file, this would cause a json unmarshalling error to
occur when we later try to go follow the file.
So brute force set it to the end if any tailing occurred.
There is potential that there could be some missing log messages if logs
are being written very quickly, however I was not able to make this
happen even with `while true; do echo hello; done`, so this is probably
acceptable.
While testing this I also found a panic in LogWatcher.Close can be
called twice due to a race. Fix channel close to only close when there
has been no signal to the channel.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: c57faa91e2dab72a0a0905dc10e5cbdf55b545f5
Component: engine
- downcase and privatize exported variables that were unused
- make accurate an error message
- added package comments
- remove unused var ReadLogsNotSupported
- enable linter
- some spelling corrections
Signed-off-by: Morgan Bauer <mbauer@us.ibm.com>
Upstream-commit: ccbe539e86dfbb8749c09763ddfd73bf10ac57cc
Component: engine
Implement new reader interface on jsonfile.
Moves jsonlog decoding from daemon to jsonfile logger.
Signed-off-by: Brian Goff <cpuguy83@gmail.com>
Upstream-commit: c0391bf5545afef5e675138556c39e4c0e9bf91b
Component: engine
- noplog driver pkg for '--log-driver=none' (null object pattern)
- centralized factory for log drivers (instead of case/switch)
- logging drivers registers themselves to factory upon import
(easy plug/unplug of drivers in daemon/logdrivers.go)
- daemon now doesn't start with an invalid log driver
- Name() method of loggers is actually now their cli names (made it useful)
- generalized Read() logic, made it unsupported except json-file (preserves
existing behavior)
Spotted some duplication code around processing of legacy json-file
format, didn't touch that and refactored in both places.
Signed-off-by: Ahmet Alp Balkan <ahmetalpbalkan@gmail.com>
Upstream-commit: 3a8728b431df07249ad913ea9a12e27dc39b8956
Component: engine
Brian Goff
Daniel Nephin
Derek McGowan
Jim Minter
Joseph Rothrock
Yanqiang Miao
Nalin Dahyabhai
Alexander Morozov
David Calavera
Shijiang Wei
Ingo Gottwald
daehyeok mun
Daniel Dao
Lei Jitang
Morgan Bauer
wlan0
Ahmet Alp Balkan
unclejack