Drop dependency on m-mizutani/golambda

[errm]

This pull request removes the dependency on the golambda package and replaces its logging and error handling with standard Go libraries and the new log/slog package. It also introduces a new utility in pkg/sqs for extracting S3 events from SQS batches, along with comprehensive unit tests. Additionally, the codebase is refactored to use clearer, more idiomatic error messages and logging, and a new logging handler is provided for AWS Lambda integration.

Key changes:

Dependency and logging refactor:

• Removed the golambda package from the codebase and replaced its logging with Go's standard log/slog package, updating all affected files and import statements accordingly. (filter.go, pkg/models/rule.go, pkg/service/cloudtrail.go, pkg/service/slack.go, go.mod) [1] [2] [3] [4] [5] [6]
• Updated error handling throughout the codebase to use standard errors and fmt.Errorf with descriptive messages instead of golambda.NewError and golambda.WrapError. (pkg/models/rule.go, pkg/service/cloudtrail.go, pkg/service/slack.go) [1] [2] [3] [4] [5] [6] [7] [8]

New features and utilities:

• Added pkg/sqs/sqs.go with an ExtractEvents function to decode S3 event notifications from SQS batches containing SNS payloads, and provided thorough unit tests in pkg/sqs/sqs_test.go. [1] [2]
• Introduced pkg/log/handler.go to provide a slog.Handler configured for AWS Lambda, including request metadata and configurable log levels via environment variables.

Testing and consistency improvements:

• Updated tests to match new error messages and logging, ensuring consistency with the refactored error handling and logging approach. (pkg/service/cloudtrail_test.go, pkg/service/slack_test.go, rule_test.go) [1] [2] [3] [4] [5] [6] [7] [8] [9]

[Copilot]

Pull request overview

This PR removes the dependency on m-mizutani/golambda by switching to the upstream AWS Lambda Go runtime (aws-lambda-go/lambda) and replacing golambda-specific event/error/logging utilities with in-repo and standard-library equivalents.

Changes:

• Replaced golambda-based Lambda entrypoint with lambda.Start and added SQS(SNS(S3)) extraction logic.
• Migrated logging to log/slog with a new pkg/log handler to emit JSON logs enriched with Lambda context.
• Replaced golambda error helpers with fmt.Errorf / errors.New across services and models; updated tests accordingly.

Reviewed changes

Copilot reviewed 9 out of 10 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
uguisu.go	Switches handler to lambda.Start, adds extractEvents, threads context.Context into processing, updates logging.
pkg/log/handler.go	New slog JSON handler with LOG_LEVEL parsing and Lambda request context attributes.
pkg/service/slack.go	Removes golambda errors/logger usage; uses stdlib errors + slog.
pkg/service/cloudtrail.go	Removes golambda error wrapping; uses fmt.Errorf wrapping.
pkg/models/rule.go	Removes golambda error construction; uses fmt.Errorf.
filter.go	Replaces golambda logger usage with slog.
uguisu_test.go	Updates tests to call new run(ctx, []events.S3Event) signature.
rule_test.go	Updates rule tests to call new run(ctx, []events.S3Event) signature.
go.mod / go.sum	Drops golambda and related transitive dependencies.

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[Copilot]

Pull request overview

Copilot reviewed 14 out of 15 changed files in this pull request and generated 4 comments.

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[bermannoah]

Nice one, thank you @errm !