[jefchien]

Description of changes

Add file tailing support to the opentelemetry config section via the filelogreceiver, at opentelemetry.collect.files.collect_list.

• Extended the filelog receiver translator with options for encoding, multiline, timestamp parsing, resource attributes, and file_storage
• Created per-entry pipeline in translator/translate/otel/pipeline/opentelemetry/files/ (receiver dedup by config hash)
  • Default log group: /aws/cwagent/files
  • Default log stream: {host.id}/{file.name}
• Schema validation in translator/config/schema.json
• Extracted strftime-to-regex and strftime-to-Go-layout maps into shared internal/util/timestamp/ package

Supported fields (matching v1 naming): file_path, log_group_name, log_stream_name, multi_line_start_pattern, timestamp_format, timezone, encoding.

License

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Tests

Added and updated unit tests. Added sample config for the new configuration option. Tested E2E on EC2 to validate tailing, default log group/stream, custom log group/stream, multi-line, receiver dedup, timestamp parsing, and state persistence/resume.

Requirements

Before commiting your code, please do the following steps.

1. Run make fmt and make fmt-sh
2. Run make lint

---

Integration Tests

To run integration tests against this PR, add the ready for testing label.

[github-actions]

Binary Size Report

linux/amd64

Binary	PR	vs main (60b2321)	vs v1.300070.0
amazon-cloudwatch-agent	233.3 MB	${\color{red}▲}$ +36.9 KB (+0.0%)	${\color{red}▲}$ +2.0 MB (+0.8%)
amazon-cloudwatch-agent-config-wizard	2.0 MB	+0 B	${\color{red}▲}$ +86.0 KB (+4.5%)
config-downloader	2.0 MB	+0 B	${\color{red}▲}$ +86.0 KB (+4.5%)
config-translator	2.0 MB	+0 B	${\color{red}▲}$ +86.0 KB (+4.5%)
start-amazon-cloudwatch-agent	2.5 MB	+0 B	${\color{red}▲}$ +81.9 KB (+3.4%)
workload-discovery	3.0 MB	+0 B	${\color{red}▲}$ +86.0 KB (+2.9%)
Total	244.8 MB	${\color{red}▲}$ +36.9 KB (+0.0%)	${\color{red}▲}$ +2.4 MB (+1.0%)

linux/amd64 amazon-cloudwatch-agent (last 9 main commits + this PR)

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 MB  └────────────────────────────────────────
      42a07a3                             PR

Notable changes:

• +1.6 MB at 98e058f

linux/arm64

Binary	PR	vs main (60b2321)	vs v1.300070.0
amazon-cloudwatch-agent	212.2 MB	${\color{red}▲}$ +65.5 KB (+0.0%)	${\color{red}▲}$ +720.9 KB (+0.3%)
amazon-cloudwatch-agent-config-wizard	2.0 MB	+0 B	${\color{green}▼}$ 22 B (-0.0%)
config-downloader	2.0 MB	+0 B	${\color{green}▼}$ 22 B (-0.0%)
config-translator	2.0 MB	+0 B	${\color{green}▼}$ 22 B (-0.0%)
start-amazon-cloudwatch-agent	2.4 MB	+0 B	${\color{red}▲}$ +65.5 KB (+2.8%)
workload-discovery	2.9 MB	+0 B	${\color{red}▲}$ +65.5 KB (+2.3%)
Total	223.5 MB	${\color{red}▲}$ +65.5 KB (+0.0%)	${\color{red}▲}$ +851.8 KB (+0.4%)

windows/amd64

Binary	PR	vs main (60b2321)	vs v1.300070.0
amazon-cloudwatch-agent.exe	236.2 MB	${\color{red}▲}$ +45.6 KB (+0.0%)	${\color{red}▲}$ +2.1 MB (+0.9%)
amazon-cloudwatch-agent-config-wizard.exe	2.1 MB	+0 B	${\color{red}▲}$ +130.6 KB (+6.5%)
config-downloader.exe	2.1 MB	+0 B	${\color{red}▲}$ +130.0 KB (+6.5%)
config-translator.exe	2.1 MB	+0 B	${\color{red}▲}$ +130.6 KB (+6.5%)
start-amazon-cloudwatch-agent.exe	2.3 MB	+0 B	${\color{red}▲}$ +112.1 KB (+5.2%)
workload-discovery.exe	2.9 MB	+0 B	${\color{red}▲}$ +91.6 KB (+3.3%)
Total	247.9 MB	${\color{red}▲}$ +45.6 KB (+0.0%)	${\color{red}▲}$ +2.6 MB (+1.1%)

Investigating size changes

Use go-size-analyzer to compare binaries:

GOEXPERIMENT=jsonv2 go install github.com/Zxilly/go-size-analyzer/cmd/gsa@latest
gsa diff --old <baseline-binary> --new <new-binary>

[JayPolanco]

Maybe a nit: The json schema has 3 enums it allows, but the if condition here only targets 2 of the 3