Release v0.8.0: Job Result Storage and Simplified Migration System

### Major Features Added
- **Job Result Storage**: Store and retrieve job execution results with TTL support
  - ResultStorage enum (Database/Memory/None) for flexible storage strategies
  - JobHandlerWithResult type for handlers returning result data
  - Automatic result storage in worker processing loop
  - TTL support with automatic expiration and cleanup
  - Comprehensive test coverage and examples

- **Simplified Migration System**: Cargo subcommand-only approach
  - cargo hammerwork migrate/status commands for schema management
  - 6 versioned migrations covering Hammerwork evolution (v0.1.0-v0.8.0)
  - Database-specific optimizations (PostgreSQL JSONB vs MySQL JSON)
  - Migration tracking table for execution history

### Breaking Changes
- Removed create_tables() and run_migrations() methods from DatabaseQueue
- Removed standalone migrate binary
- All examples now require running cargo hammerwork migrate first
- Database setup exclusively via cargo subcommand for cleaner separation

### Enhanced Architecture
- Split monolithic queue.rs into separate PostgreSQL/MySQL modules
- Cleaner DatabaseQueue trait focused on job operations only
- Production-ready workflow: migrations during deployment, not startup
- Standard Rust ecosystem practices with cargo subcommand

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: CodingAnarchy

CHANGELOG.md

@@ -5,6 +5,91 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.8.0] - 2025-06-27
+
+### Added
+- **🔧 Cargo Subcommand for Database Migrations**
+  - `cargo hammerwork migrate` command for running database migrations
+  - `cargo hammerwork status` command for checking migration status
+  - Progressive schema evolution with versioned migrations (001-006)
+  - Database-specific optimizations (PostgreSQL JSONB vs MySQL JSON)
+  - Migration tracking table for execution history and rollback safety
+- **💾 Comprehensive Job Result Storage**
+  - `ResultStorage` enum with `Database`, `Memory`, and `None` options for flexible result storage strategies
+  - `ResultConfig` struct with TTL support, max size limits, and configurable storage backends
+  - `JobResult` struct for structured result data returned by enhanced job handlers
+  - Automatic result storage when jobs complete successfully with configurable expiration
+  - Result retrieval, deletion, and cleanup operations integrated into the DatabaseQueue trait
+
+- **🔧 Enhanced Job Handler System**
+  - `JobHandlerWithResult` type for handlers that return result data alongside success/failure status
+  - Dual handler system maintaining 100% backward compatibility with existing `JobHandler` implementations
+  - `JobResult::success()` and `JobResult::with_data()` constructors for flexible result creation
+  - Automatic result storage integration in worker processing loop
+
+- **🗄️ Database Schema and Implementation Enhancements**
+  - Added `result_data`, `result_stored_at`, `result_expires_at` columns to job tables
+  - PostgreSQL implementation using JSONB for efficient result storage and queries
+  - MySQL implementation using JSON with string-based UUID handling
+  - Split monolithic queue implementation into separate PostgreSQL and MySQL modules for better maintainability
+  - Optimized queries for result storage, retrieval, and expiration cleanup
+
+- **⚡ Advanced Result Management API**
+  - `store_job_result()` - Store result data with optional TTL expiration
+  - `get_job_result()` - Retrieve stored results with automatic expiration checking
+  - `delete_job_result()` - Manual result cleanup
+  - `cleanup_expired_results()` - Batch cleanup of expired results returning count
+  - TTL support with automatic expiration based on configurable time-to-live settings
+
+- **👷 Worker Integration and Compatibility**
+  - `Worker::new_with_result_handler()` constructor for enhanced result-storing workers
+  - Automatic result storage when jobs complete successfully (respects job configuration)
+  - Legacy handler compatibility - existing workers continue to work unchanged
+  - `JobHandlerType` enum for internal handler type management and routing
+
+- **🧪 Comprehensive Testing Suite**
+  - 8 new result storage tests covering all functionality across PostgreSQL and MySQL
+  - Worker integration tests using WorkerPool approach for realistic testing scenarios
+  - Result expiration and TTL testing with time-based validation
+  - Legacy handler compatibility testing ensuring backward compatibility
+  - Configuration testing for all result storage modes and settings
+
+- **📖 Documentation and Examples**  
+  - Complete `result_storage_example.rs` demonstrating all result storage features
+  - Database-specific implementations to handle complex generic constraints
+  - Basic storage, enhanced workers, result expiration, and legacy compatibility examples
+  - Visual feedback using emoji indicators for clear demonstration output
+  - Comprehensive documentation for result storage configuration and usage
+
+### Enhanced
+- **Job Structure**: Added result configuration fields with builder methods
+  - `with_result_storage()` - Configure storage backend (Database, Memory, None)
+  - `with_result_ttl()` - Set time-to-live for result expiration
+  - `with_result_config()` - Apply complete result configuration
+- **Database Queue**: Extended trait with result storage operations
+- **Library Exports**: Added new result storage types to public API
+- **Architecture**: Modularized queue implementations for better code organization
+
+### Removed (Breaking Changes)
+- **BREAKING**: Removed `create_tables()` method from DatabaseQueue trait
+- **BREAKING**: Removed `run_migrations()` method from DatabaseQueue trait  
+- **BREAKING**: Removed standalone `migrate` binary
+- **BREAKING**: All examples now require running `cargo hammerwork migrate` before use
+- Database setup is now exclusively handled by the cargo subcommand for better separation of concerns
+
+### Enhanced
+- **Simplified API**: Cleaner DatabaseQueue trait focused on job operations only
+- **Standard Workflow**: Database migrations follow Rust ecosystem conventions
+- **Production Ready**: Migrations run during deployment, not application startup
+- **Better Testing**: Database setup is external to application code
+
+### Technical Implementation
+- **Single Source of Truth**: Only one way to run migrations (`cargo hammerwork migrate`)
+- **Idempotent Operations**: Safe to run migrations multiple times
+- **Progressive Schema**: 6 versioned migrations covering Hammerwork's evolution (v0.1.0 to v0.8.0)
+- **Database Optimizations**: PostgreSQL JSONB vs MySQL JSON with appropriate indexing
+- **Migration Tracking**: Comprehensive execution history and rollback safety
+
 ## [0.7.1] - 2025-06-27
 
 ### Fixed

CLAUDE.md

@@ -103,4 +103,121 @@ Both PostgreSQL and MySQL implementations use a single table `hammerwork_jobs` w
 - **Transaction safety**: Uses database transactions for job state changes
 - **Type-safe job handling**: Job handlers return `Result<()>` for error handling
 - **Priority-aware scheduling**: Weighted and strict priority algorithms prevent starvation
-- **Comprehensive monitoring**: Statistics track priority distribution and performance
+- **Comprehensive monitoring**: Statistics track priority distribution and performance
+
+## Rust Library Development Best Practices
+
+### Pre-Commit Quality Checks (REQUIRED)
+
+**ALWAYS run these commands before committing and pushing any changes:**
+
+```bash
+# 1. Format code according to Rust standards
+cargo fmt
+
+# 2. Run all linting checks with strict warnings
+cargo clippy --all-features -- -D warnings
+
+# 3. Run complete test suite with all features
+cargo test --all-features
+
+# 4. Verify examples compile and work
+cargo check --examples --all-features
+
+# 5. Build release version to catch optimization issues
+cargo build --release --all-features
+```
+
+### Code Quality Standards
+
+1. **Code Formatting**
+   - Use `cargo fmt` for consistent formatting
+   - Follow Rust naming conventions (snake_case, PascalCase, SCREAMING_SNAKE_CASE)
+   - Keep line length reasonable (under 100 characters when possible)
+
+2. **Documentation**
+   - Document all public APIs with `///` doc comments
+   - Include examples in doc comments where helpful
+   - Update CHANGELOG.md for all user-facing changes
+   - Maintain CLAUDE.md for development guidance
+
+3. **Testing Strategy**
+   - Write unit tests for all core functionality
+   - Include integration tests for database operations
+   - Test with both PostgreSQL and MySQL features
+   - Cover edge cases and error conditions
+   - Use `#[ignore]` for tests requiring database connections
+
+4. **Error Handling**
+   - Use `thiserror` for structured error types
+   - Provide meaningful error messages
+   - Avoid unwrap() in library code
+   - Propagate errors using `?` operator
+
+5. **Dependencies & Features**
+   - Keep dependencies minimal and well-justified
+   - Use feature flags for optional functionality
+   - Ensure backward compatibility when possible
+   - Document MSRV (Minimum Supported Rust Version)
+
+6. **Performance Considerations**
+   - Profile database queries for efficiency
+   - Use appropriate indexes in schema
+   - Minimize allocations in hot paths
+   - Test with realistic data volumes
+
+### Release Process
+
+1. **Version Bumping**
+   - Follow Semantic Versioning (semver)
+   - Update version in Cargo.toml
+   - Update CHANGELOG.md with release notes
+   - Tag releases with `git tag vX.Y.Z`
+
+2. **Testing Before Release**
+   - Run full test suite: `cargo test --all-features`
+   - Test examples: `cargo run --example <name> --features <db>`
+   - Verify documentation: `cargo doc --all-features`
+   - Check packaging: `cargo package`
+
+3. **Publishing**
+   - Commit all changes with descriptive messages
+   - Push to origin: `git push origin main && git push origin --tags`
+   - Publish to crates.io: `cargo publish`
+
+### Database Development Guidelines
+
+1. **Schema Changes**
+   - Always provide migration paths
+   - Test with both PostgreSQL and MySQL
+   - Consider backward compatibility
+   - Document schema changes in CHANGELOG
+
+2. **Query Optimization**
+   - Use proper indexes for job polling
+   - Leverage database-specific features appropriately
+   - Test query performance under load
+   - Use `EXPLAIN` to analyze query plans
+
+3. **Feature Parity**
+   - Maintain functional equivalence between database backends
+   - Handle database-specific limitations gracefully
+   - Test all features with both databases
+
+### Git Workflow
+
+1. **Commit Messages**
+   - Use conventional commit format when appropriate
+   - Include clear, descriptive titles
+   - Reference issues/PRs when relevant
+   - Add co-authorship for AI-assisted development
+
+2. **Branch Management**
+   - Use descriptive branch names
+   - Keep commits focused and atomic
+   - Squash commits before merging when appropriate
+
+3. **Code Reviews**
+   - Review for correctness, performance, and maintainability
+   - Ensure tests pass on all supported platforms
+   - Verify documentation is updated

Cargo.toml

@@ -25,10 +25,11 @@ rand = "0.8"
 prometheus = { version = "0.13" }
 reqwest = { version = "0.12", features = ["json"] }
 warp = { version = "0.3" }
+clap = { version = "4.0", features = ["derive"] }
 
 [package]
 name = "hammerwork"
-version = "0.7.1"
+version = "0.8.0"
 edition = "2024"
 description = "A high-performance, database-driven job queue for Rust with PostgreSQL and MySQL support, featuring job prioritization, cron scheduling, timeouts, rate limiting, Prometheus metrics, alerting, and comprehensive statistics collection"
 license = "MIT"
@@ -57,6 +58,8 @@ rand = { workspace = true }
 prometheus = { version = "0.13", optional = true }
 reqwest = { version = "0.12", features = ["json"], optional = true }
 warp = { version = "0.3", optional = true }
+clap = { workspace = true }
+tracing-subscriber = { workspace = true }
 
 [features]
 default = ["metrics", "alerting"]
@@ -84,3 +87,7 @@ required-features = ["postgres"]
 [[example]]
 name = "priority_example"
 required-features = ["postgres"]
+
+[[bin]]
+name = "cargo-hammerwork"
+path = "src/bin/cargo-hammerwork.rs"

README.md

@@ -42,6 +42,7 @@ See the [Quick Start Guide](docs/quick-start.md) for complete examples with Post
 - **[Cron Scheduling](docs/cron-scheduling.md)** - Recurring jobs with timezone support  
 - **[Priority System](docs/priority-system.md)** - Five-level priority system with weighted scheduling
 - **[Batch Operations](docs/batch-operations.md)** - High-performance bulk job processing
+- **[Database Migrations](docs/migrations.md)** - Progressive schema updates and database setup
 - **[Monitoring & Alerting](docs/monitoring.md)** - Prometheus metrics and notification systems
 
 ## Basic Example
@@ -53,10 +54,9 @@ use std::sync::Arc;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    // Setup database and queue
+    // Setup database and queue (migrations should already be run)
     let pool = sqlx::PgPool::connect("postgresql://localhost/mydb").await?;
     let queue = Arc::new(JobQueue::new(pool));
-    queue.create_tables().await?;
 
     // Create job handler
     let handler = Arc::new(|job: Job| {
@@ -83,9 +83,45 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
 
 
 
-## Database Schema
+## Database Setup
 
-Hammerwork uses a single `hammerwork_jobs` table with optimized indexes for performance. The schema supports all features including priorities, timeouts, cron scheduling, and comprehensive job lifecycle tracking.
+### Using Migrations (Recommended)
+
+Hammerwork provides a migration system for progressive schema updates:
+
+```bash
+# Build the migration tool
+cargo build --bin cargo-hammerwork --features postgres
+
+# Run migrations
+cargo hammerwork migrate --database-url postgresql://localhost/hammerwork
+
+# Check migration status
+cargo hammerwork status --database-url postgresql://localhost/hammerwork
+```
+
+### Application Usage
+
+Once migrations are run, your application can use the queue directly:
+
+```rust
+// In your application - no setup needed, just use the queue
+let pool = sqlx::PgPool::connect("postgresql://localhost/hammerwork").await?;
+let queue = Arc::new(JobQueue::new(pool));
+
+// Start enqueuing jobs immediately
+let job = Job::new("default".to_string(), json!({"task": "send_email"}));
+queue.enqueue(job).await?;
+```
+
+### Database Schema
+
+Hammerwork uses optimized tables with comprehensive indexing:
+- **`hammerwork_jobs`** - Main job table with priorities, timeouts, cron scheduling, and result storage
+- **`hammerwork_batches`** - Batch metadata and tracking (v0.7.0+)
+- **`hammerwork_migrations`** - Migration tracking for schema evolution
+
+The schema supports all features including job prioritization, timeouts, cron scheduling, batch processing, result storage, and comprehensive lifecycle tracking. See [Database Migrations](docs/migrations.md) for details.
 
 ## Development