http_server: v2: reload: windows: Enable hot reloading

[cosmo0920]

Building on top of calyptia-fleet works on Windows, we can also offer for enabling hot-reloading on Windows. :)

However, Windows does not have SIGHUP signal. So, I enabled only for HTTP API for reloading.

Note that GenerateConsoleCtrlEvent returns nonzero when succeeded.

ref: https://learn.microsoft.com/en-us/windows/console/generateconsolectrlevent

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Enter [N/A] in the box, if an item is not applicable to your change.

Testing
Before we can approve your change; please submit the following in a comment:

• Example configuration file for the change

PS> bin/fluent-bit -i random -o stdout -H -P 2020 -Y -v

• Debug log output from testing the change

On Another Terminal

PS>  curl -XPOST -d '{}' http://localhost:2020/api/v2/reload
{"reload":"done","status":1}

Fluent Bit Terminal

Fluent Bit v2.1.10
* Copyright (C) 2015-2022 The Fluent Bit Authors
* Fluent Bit is a CNCF sub-project under the umbrella of Fluentd
* https://fluentbit.io

[2023/09/28 12:40:59] [ info] Configuration:
[2023/09/28 12:40:59] [ info]  flush time     | 1.000000 seconds
[2023/09/28 12:40:59] [ info]  grace          | 5 seconds
[2023/09/28 12:40:59] [ info]  daemon         | 0
[2023/09/28 12:40:59] [ info] ___________
[2023/09/28 12:40:59] [ info]  inputs:
[2023/09/28 12:40:59] [ info]      random
[2023/09/28 12:40:59] [ info] ___________
[2023/09/28 12:40:59] [ info]  filters:
[2023/09/28 12:40:59] [ info] ___________
[2023/09/28 12:40:59] [ info]  outputs:
[2023/09/28 12:40:59] [ info]      stdout.0
[2023/09/28 12:40:59] [ info] ___________
[2023/09/28 12:40:59] [ info]  collectors:
[2023/09/28 12:40:59] [ info] [fluent bit] version=2.1.10, commit=b19e9ce674, pid=27336
[2023/09/28 12:40:59] [debug] [engine] coroutine stack size: 98302 bytes (96.0K)
[2023/09/28 12:40:59] [ info] [storage] ver=1.5.1, type=memory, sync=normal, checksum=off, max_chunks_up=128
[2023/09/28 12:40:59] [ info] [cmetrics] version=0.6.3
[2023/09/28 12:40:59] [ info] [ctraces ] version=0.3.1
[2023/09/28 12:40:59] [ info] [input:random:random.0] initializing
[2023/09/28 12:40:59] [ info] [input:random:random.0] storage_strategy='memory' (memory only)
[2023/09/28 12:40:59] [debug] [random:random.0] created event channels: read=848 write=852
[2023/09/28 12:40:59] [debug] [input:random:random.0] interval_sec=1 interval_nsec=0
[2023/09/28 12:40:59] [debug] [stdout:stdout.0] created event channels: read=856 write=860
[2023/09/28 12:40:59] [ info] [http_server] listen iface=0.0.0.0 tcp_port=2020
[2023/09/28 12:40:59] [ info] [sp] stream processor started
[2023/09/28 12:40:59] [ info] [output:stdout:stdout.0] worker #0 started
[2023/09/28 12:41:00] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:01] [debug] [task] created task=000001FB96EA2920 id=0 OK
[0] random.0: [[1695872460.781617500, {}], {"rand_value"=>[2023/09/28 12:41:01] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
3917686252860891653}]
[2023/09/28 12:41:01] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:01] [debug] [out flush] cb_destroy coro_id=0
[2023/09/28 12:41:01] [debug] [task] destroy task=000001FB96EA2920 (task_id=0)
[2023/09/28 12:41:02] [debug] [task] created task=000001FB96EA2920 id=0 OK
[2023/09/28 12:41:02] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[0] random.0: [[1695872461.776284700, [2023/09/28 12:41:02] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
{}], {"rand_value"=>8350676561454476613}]
[2023/09/28 12:41:02] [debug] [out flush] cb_destroy coro_id=1
[2023/09/28 12:41:02] [debug] [task] destroy task=000001FB96EA2920 (task_id=0)
[2023/09/28 12:41:03] [debug] [task] created task=000001FB96EA2920 id=0 OK
[0] random.0: [[1695872462.786276300, {}], {"rand_value"=>5297848698850845187}]
[2023/09/28 12:41:03] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2023/09/28 12:41:03] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:03] [debug] [out flush] cb_destroy coro_id=2
[2023/09/28 12:41:03] [debug] [task] destroy task=000001FB96EA2920 (task_id=0)
[2023/09/28 12:41:04] [debug] [task] created task=000001FB96EA2920 id=0 OK
[0] random.0: [[1695872463.786365700, {}], {"rand_value"=>13289125307504265363}]
[2023/09/28 12:41:04] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2023/09/28 12:41:04] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:04] [debug] [out flush] cb_destroy coro_id=3
[2023/09/28 12:41:04] [debug] [task] destroy task=000001FB96EA2920 (task_id=0)
[2023/09/28 12:41:05] [debug] [task] created task=000001FB96EA2920 id=0 OK
[0] random.0: [[1695872464.781742700, {}], {"rand_value"=>7913022013376780552}]
[2023/09/28 12:41:05] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2023/09/28 12:41:05] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:05] [debug] [out flush] cb_destroy coro_id=4
[2023/09/28 12:41:05] [debug] [task] destroy task=000001FB96EA2920 (task_id=0)
[2023/09/28 12:41:06] [debug] [task] created task=000001FB96EA2920 id=0 OK
[0] random.0: [[1695872465.781798000, {}], {"rand_value"=>5159549540827597325}]
[2023/09/28 12:41:06] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2023/09/28 12:41:06] [debug] [out flush] cb_destroy coro_id=5
[2023/09/28 12:41:06] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:06] [debug] [task] destroy task=000001FB96EA2920 (task_id=0)
[2023/09/28 12:41:06] [ info] reloading instance pid=27336 tid=000001FB96EC2A90
[2023/09/28 12:41:06] [ info] [reload] stop everything of the old context
[2023/09/28 12:41:06] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2023/09/28 12:41:06] [ warn] [engine] service will shutdown when all remaining tasks are flushed
[0] random.0: [[1695872466.781374300, {}], {"rand_value"=>18407437581212968048}]
[2023/09/28 12:41:06] [ info] [input] pausing random.0
[2023/09/28 12:41:07] [ info] [engine] service has stopped (0 pending tasks)
[2023/09/28 12:41:07] [ info] [input] pausing random.0
[2023/09/28 12:41:07] [ info] [output:stdout:stdout.0] thread worker #0 stopping...
[2023/09/28 12:41:07] [ info] [output:stdout:stdout.0] thread worker #0 stopped
[2023/09/28 12:41:09] [ info] [reload] start everything
[2023/09/28 12:41:09] [ info] [fluent bit] version=2.1.10, commit=b19e9ce674, pid=27336
[2023/09/28 12:41:09] [debug] [engine] coroutine stack size: 98302 bytes (96.0K)
[2023/09/28 12:41:09] [ info] [storage] ver=1.5.1, type=memory, sync=normal, checksum=off, max_chunks_up=128
[2023/09/28 12:41:09] [ info] [cmetrics] version=0.6.3
[2023/09/28 12:41:09] [ info] [ctraces ] version=0.3.1
[2023/09/28 12:41:09] [ info] [input:random:random.0] initializing
[2023/09/28 12:41:09] [ info] [input:random:random.0] storage_strategy='memory' (memory only)
[2023/09/28 12:41:09] [debug] [random:random.0] created event channels: read=1140 write=1144
[2023/09/28 12:41:09] [debug] [input:random:random.0] interval_sec=1 interval_nsec=0
[2023/09/28 12:41:09] [debug] [stdout:stdout.0] created event channels: read=1148 write=1152
[2023/09/28 12:41:09] [ info] [http_server] listen iface=0.0.0.0 tcp_port=2020
[2023/09/28 12:41:09] [ info] [sp] stream processor started
[2023/09/28 12:41:09] [ info] [output:stdout:stdout.0] worker #0 started
[2023/09/28 12:41:10] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:11] [debug] [task] created task=000001FB96F5C9E0 id=0 OK
[0] random.0: [[1695872470.879987800, {}], {"rand_value"=>3196691273628167248}]
[2023/09/28 12:41:11] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[2023/09/28 12:41:11] [debug] [input chunk] update output instances with new chunk size diff=50, records=1, input=random.0
[2023/09/28 12:41:11] [debug] [out flush] cb_destroy coro_id=0
[2023/09/28 12:41:11] [debug] [task] destroy task=000001FB96F5C9E0 (task_id=0)
[2023/09/28 12:41:12] [debug] [task] created task=000001FB96F5CA80 id=0 OK
[2023/09/28 12:41:12] [debug] [output:stdout:stdout.0] task_id=0 assigned to thread #0
[0] random.0: [[1695872471.888636300, {}], {"rand_value"=>12186872785323929565}]

• Attached Valgrind output that shows no leaks or memory corruption was found

If this is a change to packaging of containers or native binaries then please confirm it works for all targets.

• Run local packaging test showing all targets (including any new ones) build.
• Set ok-package-test label to test for all targets (requires maintainer to do).

Documentation

• Documentation required for this feature

fluent/fluent-bit-docs#1209

Backporting

• Backport to latest stable release.

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Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.