cull-gmail/WARP.md

WARP.md

This file provides guidance to WARP (warp.dev) when working with code in this repository.

Core Development Commands

Build and Test

• Build: cargo build
• Test: cargo test
• Format: cargo fmt --all
• Lint: cargo clippy --all-targets --all-features -- -D warnings
• CI test runner: cargo nextest run --profile ci

CLI Development

• Install CLI locally: cargo install --path .
• Run CLI without installing: cargo run --bin cull-gmail -- --help
• Test a single test by pattern: cargo test test_rules_new_creates_default_rules

Special Tests

• Run ignored Gmail API integration test: cargo test --test gmail_message_list_integration -- --ignored
  • Requires valid OAuth2 credentials configured
  • Only use with test Gmail account

High-level Architecture

Crates

• Library: cull_gmail - Core Gmail management functionality
• Binary: cull-gmail - CLI application

Core Components

• GmailClient: Async Gmail API client with OAuth2 authentication, refresh token persistence, and Gmail API request helpers
• Rules/EolRule: Rule-based message lifecycle engine that loads from TOML configuration and evaluates messages to yield actions (trash/delete)
• ClientConfig: Configuration loader that merges TOML files with environment variables using APP_ prefix
• MessageList: Abstraction over sets of Gmail message IDs with support for batch list, trash, and delete operations
• CLI: Command-line interface with subcommands for labels, messages, rules, and token; implements dry-run-first behavior for safety

CLI Subcommands

• labels - List and inspect available Gmail labels
• messages - Query, filter, and perform batch operations on Gmail messages
• rules - Configure and execute automated message retention rules
• token - Export/import OAuth2 tokens for ephemeral environments

Runtime

• Async/await: All network operations use Tokio async runtime
• OAuth2: Uses installed application flow with token caching to ~/.cull-gmail/gmail1/
• Safety: Dry-run mode by default; destructive actions require explicit execution flags

Configuration

Directory Structure

• Config directory: ~/.cull-gmail/
• Main config: cull-gmail.toml
• Rules config: rules.toml
• OAuth2 tokens: gmail1/ subdirectory

Configuration Sources (in precedence order)

1. Environment variables with APP_ prefix
2. TOML configuration files
3. Built-in defaults

OAuth2 Setup Requirements

1. Google Cloud Console project with Gmail API enabled
2. OAuth2 desktop application credentials
3. Download credential JSON to config directory
4. First run triggers browser authentication flow

Testing

Test Organization

• Unit tests: Alongside modules in src/
• Integration tests: In tests/ directory
• CI runner: Uses nextest with ci profile from .config/nextest.toml

Test Categories

• Standard tests: cargo test or cargo nextest run --profile ci
• Gmail API integration test (ignored by default): Requires valid credentials and network access

Important Notes

• MSRV: Rust 1.88+ (edition 2024)
• Required runtime: Tokio for all async operations
• Gmail API: Requires valid OAuth2 credentials for real testing
• Logging: Use RUST_LOG=cull_gmail=debug for detailed operation logs
• Safety: All operations default to dry-run mode; use explicit execution flags for actual changes