parser: Add IANA time_zone support for native timestamps

[cosmo0920]

This is 2nd attempt of adding IANA compatible time_zone support for system time.

This work is based on #11639 which is @arnikola's work.

---

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

Example config files taken from #11639 (comment):
config.conf:

[SERVICE]
    Parsers_File  parsers.conf

[INPUT]
    Name          tail
    Path          tz-example.log
    Tag           tz.test
    Parser        tz_naive
    Read_from_Head true
    Exit_On_Eof   true

[OUTPUT]
    Name          stdout
    Match         tz.test
    Format        json_lines

parsers.conf

[PARSER]
    Name         tz_naive
    Format       regex
    Regex        ^(?<ts>[^ ]+) (?<msg>.+)$
    Time_Key     ts
    Time_Format  %Y-%m-%dT%H:%M:%S
    Time_Keep    On
    Time_Strict  On
    Time_Zone    Australia/Sydney

• Debug log output from testing the change

• 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

Backporting

• Backport to latest stable release.

---

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.

Summary by CodeRabbit

• New Features

  • Added per-parser IANA Time_Zone support so parsers convert naive timestamps using a configured zone; invalid or conflicting timezone combinations are rejected

• Tests

  • Added unit and integration tests for IANA timezone conversion, missing-year handling, conflict validation, and platform-specific zone availability checks

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 71ed0cd8-da2c-4010-baa1-20008e37fccb

📥 Commits

Reviewing files that changed from the base of the PR and between 5ebf14e and 6a16277.

📒 Files selected for processing (2)

• include/fluent-bit/flb_parser.h
• src/flb_parser.c

🚧 Files skipped from review as they are similar to previous changes (2)

• include/fluent-bit/flb_parser.h
• src/flb_parser.c

---

📝 Walkthrough

Walkthrough

Fluent Bit parsers now accept per-parser IANA Time_Zone, validate/load platform-specific zone data (Windows IANA→native or POSIX tzif), convert naive timestamps with the configured zone, wire Time_Zone into config/creation, update format parsers to use the new converter, and add unit/integration tests plus a CI change.

Changes

IANA Timezone Parser Feature

Layer / File(s)	Summary
Timezone API and validation infrastructure include/fluent-bit/flb_parser.h, src/flb_parser.c	Adds parser->time_zone and parser->time_zone_data, declares/implements flb_parser_tm2time_parser(), and implements Windows IANA→native mapping and POSIX tzif loading/validation.
Parser creation factory and lifecycle management src/flb_parser.c	New exported flb_parser_create_with_time_zone(); flb_parser_create() becomes a wrapper; early validation enforces time_zone requires time_format and disallows incompatible combos; destroy frees time_zone/time_zone_data.
Configuration loading for timezone parameter src/flb_parser.c	Loads Time_Zone from parser config sections, passes it into the new factory, and frees the loaded string on success and error paths.
Format-specific parser time conversion src/flb_parser_json.c, src/flb_parser_logfmt.c, src/flb_parser_ltsv.c, src/flb_parser_regex.c	JSON, logfmt, LTSV, and regex parsers now call flb_parser_tm2time_parser(&tm, parser) when converting parsed struct flb_tm into time_lookup.
Time lookup conditional logic src/flb_parser.c	Missing-year normalization and GMToff assignment use the configured IANA zone for naive timestamps; time_offset is applied only when no time_system_timezone and no time_zone are configured.
Unit test platform support and IANA tests tests/internal/parser.c	Adds platform-aware test helpers (flb_test_tzset, env helpers, timezone availability), updates an existing midnight test, and adds multiple IANA timezone unit tests including conflict validation.
Regex parser timezone test cases tests/internal/parser_regex.c	Adds timezone_available() helper and test_time_zone() validating flb_parser_create_with_time_zone() across zones/dates with exact epoch checks.
Integration tests for tail input with timezone tests/integration/scenarios/in_tail/config/parsers_tail_it.conf, tests/integration/scenarios/in_tail/config/tail_parser_time_zone.yaml, tests/integration/scenarios/in_tail/tests/test_in_tail_001.py	Adds iana_timezone parser, tail integration config, and a Python integration test that conditionally verifies timestamp conversion from America/New_York to UTC.
Windows unit-test workflow adjustment .github/workflows/call-windows-unit-tests.yaml	Removed -D FLB_WITHOUT_flb-it-parser=On from Windows unit-test CMake invocation so parser-related tests run in Windows CI.

Estimated code review effort

🎯 4 (Complex) | ⏱️ ~60 minutes

Possibly related PRs

• fluent/fluent-bit#11903: Introduces Windows↔IANA timezone conversion helpers consumed by this PR's parser timezone logic.
• fluent/fluent-bit#11677: Modifies flb_parser_time_lookup() timezone and midnight handling; overlaps with GMToff and year-normalization changes here.

Suggested reviewers

• edsiper
• niedbalski
• celalettin1286

Poem

🐰 I found a zone called New York town,

I learned its folds from files and Windows frown,
I hop through tzif and map to native names,
I nudge naive clocks to UTC frames,
Now timestamps sleep sound, no more timezone clown.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 5.71% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main change: adding IANA time_zone support for naive timestamps in the parser, which is clearly reflected across the entire changeset including new struct fields, functions, and comprehensive tests.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch cosmo0920-parser-timezone-iana-symbols-on-windows

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 Infer (1.2.0)

src/flb_parser.c

src/flb_parser.c:20:10: fatal error: 'fluent-bit/flb_info.h' file not found
20 | #include <fluent-bit/flb_info.h>
| ^~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
Error: the following clang command did not run successfully:
/opt/infer-linux-x86_64-v1.2.0/lib/infer/facebook-clang-plugins/clang/install/bin/clang-18
@/tmp/coderabbit-infer/6a162775425a897266899b864ca5cd547815b13e-db7608c4d518ccbb/tmp/clang_command_.tmp.874190.txt
++Contents of '/tmp/coderabbit-infer/6a162775425a897266899b864ca5cd547815b13e-db7608c4d518ccbb/tmp/clang_command_.tmp.874190.txt':
"-cc1" "-load"
"/opt/infer-linux-x86_64-v1.2.0/lib/infer/infer/bin/../../facebook-clang-plugins/libtooling/build/FacebookClangPlugin.dylib"
"-add-plugin" "BiniouASTExporter" "-plugin-arg-BiniouASTExporter" "-"
"-plugin-arg-BiniouASTExporter" "PREPEND_CURRENT_DIR=1"
"-plugin-arg-BiniouASTExporter" "MAX_STRING_SIZE=65535" "-cc1" "-triple"
"x86_64-unknown-linux-gnu" "-emit-obj" "-mrelax-all"

... [truncated 713 characters] ...

"/opt/infer-linux-x86_64-v1.2.0/lib/infer/facebook-clang-plugins/clang/install/lib/clang/18/include"
"-internal-isystem" "/usr/local/include" "-internal-isystem"
"/usr/lib/gcc/x86_64-linux-gnu/12/../../../../x86_64-linux-gnu/include"
"-internal-externc-isystem" "/usr/include/x86_64-linux-gnu"
"-internal-externc-isystem" "/include" "-internal-externc-isystem"
"/usr/include" "-Wno-ignored-optimization-argument" "-Wno-everything"
"-ferror-limit" "19" "-fgnuc-version=4.2.1" "-fskip-odr-check-in-gmf"
"-D__GCC_HAVE_DWARF2_CFI_ASM=1" "-o"
"/tmp/coderabbit-infer/db7608c4d518ccbb/file.o" "-x" "c"
"src/flb_parser.c" "-O0" "-fno-builtin" "-include"
"/opt/infer-linux-x86_64-v1.2.0/lib/infer/infer/bin/../lib/clang_wrappers/global_defines.h"
"-Wno-everything"

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: 791d8faa02

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[patrick-stephens]

I'm thinking we can start using the defaulting options now as well?

[cosmo0920]

Not sure. This is the first time to use parsers_file in our integration tests. So, if we'll need another part of the integration test case, we'll have to implement and use the defaulting option here.

[coderabbitai]

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

src/flb_parser.c (1)

634-649: ⚠️ Potential issue | 🟠 Major | 🏗️ Heavy lift

Cache the resolved timezone at parser creation.

flb_parser_tm2time_parser() and the missing-year branch in flb_parser_time_lookup() both reload and parse the zoneinfo data for every record, while flb_parser_create_with_time_zone() only keeps the raw string. That puts blocking file I/O and TZif parsing on the parser hot path, and it means parser registration can still succeed on POSIX even when the zone file is unreadable or malformed. Resolve/parse the timezone once during creation, store the compiled state on struct flb_parser, and reuse it from both runtime paths.

Also applies to: 943-965, 1890-1905

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@src/flb_parser.c` around lines 634 - 649, The parser currently reparses
zoneinfo on each record; modify struct flb_parser to hold a parsed/compiled
timezone object (e.g., a tzif handle) and update
flb_parser_create_with_time_zone() to resolve and parse the zone file once
(failing creation if parsing fails), storing the compiled state on the
flb_parser; then change flb_parser_tm2time_parser() and the missing-year branch
in flb_parser_time_lookup() to use that stored tzif object instead of calling
tzif_load/tzif_tm2time each time, and ensure you free/destroy the cached tzif in
the parser destructor to avoid leaks.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Outside diff comments:
In `@src/flb_parser.c`:
- Around line 634-649: The parser currently reparses zoneinfo on each record;
modify struct flb_parser to hold a parsed/compiled timezone object (e.g., a tzif
handle) and update flb_parser_create_with_time_zone() to resolve and parse the
zone file once (failing creation if parsing fails), storing the compiled state
on the flb_parser; then change flb_parser_tm2time_parser() and the missing-year
branch in flb_parser_time_lookup() to use that stored tzif object instead of
calling tzif_load/tzif_tm2time each time, and ensure you free/destroy the cached
tzif in the parser destructor to avoid leaks.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 826d9b16-036e-4139-bbd2-fd91882ccaa8

📥 Commits

Reviewing files that changed from the base of the PR and between 791d8fa and 5ebf14e.

📒 Files selected for processing (2)

• src/flb_parser.c
• tests/internal/parser.c

🚧 Files skipped from review as they are similar to previous changes (1)

• tests/internal/parser.c