This finally adds support for multiple architectures!  

Images are now built using BuildKit (actually img), Dockerfiles were parameterized to allow this.
Containers are still built on alpine, using QEMU and binfmt as a kernel compatibility layer to allow RUN steps in these.

CircleCI has been fully revamped, to speed up builds and de-duplicate the configuration.
Makefile has been extended with additional logic to shadow the multi-arch to non-CI users.

Happy hacking on Raspberry Pi and friends :)

Logcli used to inconsistently handle timezones in timestamps.

This addresses this by adding a new `--timezone` / `-z` flag, to explicitly set the timezone the timestamps shall be formatted in.

Furthermore it refactors the output framework inside of logcli to test it easier.

Fixes #798 

refactor(makefile): simplify makefile by removing the autogenerated targets and make building binaries and dockerfiles separate operations.

* refactor(querier/ingester): TailRequest Lookback window

Moves the specifications of the Lookback Window out of the
logproto.QueryRequest into it's own type logproto.Lookback.
This is required, because the Lookback Window will be used in the TailRequest
as well.

* feat(querier): parse Lookback from HTTP Request

* feat(logcli): send Lookback Window spec with tail request

* feat(querier): include historic entries in tail mode

Extends tailing by sending a configurable amount of historic entries with
before the live entries. This enables a behaviour that is closer to kubectl logs
-f and docker logs -f.

It is implemented by running a regular Query before subscribing to the ingesters.

* fix: adapt tests to Lookback change

* feat(querier): check all errors to make the linter happy

* fix(logproto): flatten Lookback window spec

Flattens the Lookback window spec into the individual queries

* fix(ingester): adapt test to Lookback flatten

Fixes #774

* add benchmark for storage queries
* improve iterator to load only on next
* fix memory retained by lazy chunks
* reverse backward lazy iterator

* feat(logcli): quiet mode

Adds a quiet mode (-q / --quiet) to suppress the debug messages to stderr

* feat(logcli): output modes

Adds two alternative output modes (-o / --output)

- raw: emits the line as parsed
- jsonl: emits the line plus all known metadata as JSONL (JSON Line)

Usage: -o [default, raw, jsonl]

* feat(logcli): quiet tailing mode

* feat(logcli): output modes while tailing

Supports the three different output modes in tail mode as well

* feat(logcli): print labels in jsonl tail mode

* refactor(logcli): clean up entry printing

Moves the entry printing into a standardized interface, implements this three
times:

- default (human readable)
- jsonl (for scripts)
- raw ('as is')

* feat(logcli): query from absolute timestamp

Adds a new flag (`--from`) as to complement `--since`.
While since subtracts a relative duration from the current time, from allows to
specify the absolute start of the lookback window.

Note: `--from` takes precedence over `--since`, but only if set.

* fix(logcli): use RFC3339Nano for -from

To comply with Prometheus, this flag now honors Nanoseconds as well (was using
RFC3339 so far)

canary will suspend all operations on SIGINT but not exit, allowing you to shutdown the canary without it being restarted by docker/kubernetes
SIGTERM will shutdown everything and end the process

* fix(loki): pass missing config error to user

Missing config errors are handled at the library level. Our own check mitigated
this and causes loki to SEGFAULT later on

* feat(loki): default config file in container

The container provides a default config file. Use it by default

* Revert "fix(loki): pass missing config error to user"

This reverts commit b2744fcf427b2b386dce5e999c855ae5c899e4e2, because loki it
assumed loki was incapable of running without config, which is not the case.

When a more or less invalid config (e.g. `null`) is supplied, the log level prop
of the config receives an invalid value which causes the logger to panic on
re-init.

Prevents this by checking for a nil log-level and notifies the user in case

changing the default prune interval to 60 seconds, at the previous 1 second it would cause some way too aggressive querying when scaled out over all our clusters and loki had a hiccup

* Improvements in live tailing of logs

Instead of polling for new logs, a grpc stream is opened between ingester and querier to get live logs
Querier reconnects to disconnected or newly added ingesters

* Added more comments to code for live log tailing

* Some code refactoring in live log tailing

* handling delayfor in logcli, max delayfor to be 5 seconds

* some changes in tail response in live tailing

* Fixed issue with stopping ingesters gracefully when live tailing is being used

* Added tests for tailer in querier

* Live tailing made logql compatible, some code refactoring suggested in PR

* adds first version of docker driver

* without logrus and fixes some linter issue

* fix the driver and start a build system

* adds swarm label discovery

* Add documentation and more targets

* make the linter happy 

* indent config.json

* with circleci steps for master and branch

* Review Feebacks

refactoring things so that the comparator can use the reader to make a direct query to loki to look for logs not received over the websocket  before reporting them as missing

Because of the logger being initialized before the configuration file is parsed,
the log_level from the config file is ignored.
To solve this, the logger is reinitialized after the file is parsed, as it is
already being done in promtail.

removed helm entry in scrape_config.sh because there doesn't seem to be anyway to make it work with new pipeline config

* Reject entries based on age set in limits

* ksonnet changes for running loki in single bianry
Added retention config with default values

* Fixed indentation

* Update cortex vendor
Use query max look back from cortex
Update config changes from cortex
Fixed breaking code due to updating cortex vendor

* fixed linter error

* Fix local config: Use DayTime

Psst, the date is the first commit date for loki ;)

Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>

* Fix the config in ksonnet and helm too

Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>

Changed it to dict with single key called "streams" and value set to list of logproto.Stream

* impr/clients: Handle TLS config and MTLS for logcli and promtail

* fix/tls: Please gofmt...

* impr/clients: use prometheus HTTPClientConfig for logcli and promtail

* fix/promtail: Set proper Client config name

* impr/promtail: Use prometheus HTTPClientConfig configuration

* adapt with master

* address review

* fix conflicts

* address requested changes

* remove file

Signed-off-by: Goutham Veeramachaneni <gouthamve@gmail.com>

* impr/logcli: Added label filters + tests

* Address review

* udpate readme

* Limiting query start time with config

* Fixed maxLookBackPeriod check, added it to existing configs, some other fixes

* gofmted file

* Changed maxLookBackPeriod to 4 weeks in helm chart

* Setting maxLookBackPeriod in helm chart to 0 and bumping up the helm chart version

* changed maxLookBackPeriod in yaml in cmd to 0 and some nit

using an environment variable passed into an arg instead of reading the pod name from a file and the downardApi
added a makefile