church-api/NEXT_STEPS.md

Next Steps for Service Layer Migration

Immediate Actions Required

1. Clean Up Current EventService Import

# Remove unused import from events service
# File: src/services/events.rs line 10
# Remove: db_operations::EventOperations,

2. Migrate Remaining Modules (In Priority Order)

A. Bulletins Service (HIGH PRIORITY)

Files to create:

// src/services/bulletins.rs
pub struct BulletinService;
impl BulletinService {
    pub async fn create_v1(pool: &PgPool, req: CreateBulletinRequest, url_builder: &UrlBuilder) -> Result<Bulletin> {
        let bulletin = db::bulletins::create(pool, req).await?;
        convert_bulletin_to_v1(bulletin, url_builder)
    }
    
    pub async fn update_v1(pool: &PgPool, id: &Uuid, req: UpdateBulletinRequest, url_builder: &UrlBuilder) -> Result<Bulletin> {
        let bulletin = db::bulletins::update(pool, id, req).await?;
        convert_bulletin_to_v1(bulletin, url_builder)
    }
    
    // Add V2 methods with timezone flexibility
}

Files to modify:

• src/handlers/bulletins.rs - Replace direct db calls with BulletinService calls
• src/handlers/v2/bulletins.rs - Replace direct db calls with BulletinService calls
• src/services/mod.rs - Add pub mod bulletins; and pub use bulletins::BulletinService;

B. Users/Auth Service (HIGH PRIORITY)

Files to create:

// src/services/auth.rs
pub struct AuthService;
impl AuthService {
    pub async fn authenticate_user(pool: &PgPool, username: &str, password: &str) -> Result<User> {
        let user = db::users::get_by_username(pool, username).await?
            .ok_or_else(|| ApiError::Unauthorized("Invalid credentials".to_string()))?;
        
        let password_hash = db::users::get_password_hash(pool, &user.id).await?;
        
        // Verify password logic here
        // Return user with V1 timezone conversion if needed
    }
    
    pub async fn get_user_by_id(pool: &PgPool, id: &Uuid) -> Result<Option<User>> {
        db::users::get_by_id(pool, id).await
    }
}

Files to modify:

• src/handlers/auth.rs - Replace direct db calls with AuthService calls

C. Bible Verses Service

Files to create:

// src/services/bible_verses.rs
pub struct BibleVerseService;
impl BibleVerseService {
    pub async fn get_random_v1(pool: &PgPool) -> Result<Option<BibleVerse>> {
        let verse = BibleVerseOperations::get_random(pool).await?;
        // Apply V1 timezone conversion if needed
    }
    
    pub async fn search_v1(pool: &PgPool, query: &str, limit: i64) -> Result<Vec<BibleVerse>> {
        let verses = BibleVerseOperations::search(pool, query, limit).await?;
        // Apply V1 timezone conversion if needed
    }
}

D. Schedule Service

Files to create:

// src/services/schedule.rs
pub struct ScheduleService;
impl ScheduleService {
    pub async fn get_by_date_v1(pool: &PgPool, date: NaiveDate) -> Result<Option<Schedule>> {
        ScheduleOperations::get_by_date(pool, date).await
    }
    
    pub async fn get_for_range_v1(pool: &PgPool, start: NaiveDate, end: NaiveDate) -> Result<Vec<Schedule>> {
        ScheduleOperations::get_for_range(pool, start, end).await
    }
}

E. Config Service (LOW PRIORITY)

Files to create:

// src/services/config.rs
pub struct ConfigService;
impl ConfigService {
    pub async fn update_config(pool: &PgPool, config: ChurchConfig) -> Result<ChurchConfig> {
        // Add business logic validation here
        db::config::update_config(pool, config).await
    }
}

Migration Checklist Template

For each module, follow this checklist:

Service Creation

• Create src/services/{module}.rs
• Implement {Module}Service struct
• Add V1 methods that call db::{module}::* functions
• Add V2 methods with timezone flexibility
• Apply proper timezone conversions and URL building

Handler Migration

• Update imports to use service instead of direct db calls
• Replace db::{module}::* calls with {Module}Service::* calls
• Ensure handlers stay thin (no business logic)
• Test that all endpoints still work

Module Registration

• Add pub mod {module}; to src/services/mod.rs
• Add pub use {module}::{Module}Service; to src/services/mod.rs

Verification

• Run cargo build and confirm specific "unused" warnings eliminated
• Test API endpoints to ensure functionality preserved
• Verify timezone conversion working correctly

Expected Results After Full Migration

Warning Reduction

• Current: 64 warnings
• Target: ~45-50 warnings
• Eliminated: ~15-20 legitimate "unused function" warnings

Architecture Achieved

• Thin handlers - HTTP concerns only
• Service layer - All business logic centralized
• Database layer - Data access properly abstracted
• Dumb frontend - No logic, just displays backend data

Maintainability Gains

• Business logic changes only require service layer updates
• Easy to add caching, validation, authorization at service level
• Clear separation of concerns
• Better testability

Files That Will Remain "Unused" (Legitimate)

These are utility functions for future features and can be ignored:

• src/utils/response.rs helper functions
• src/utils/database.rs generic utilities
• src/utils/datetime.rs display formatting functions
• src/utils/validation.rs optional validation methods
• src/utils/handlers.rs generic handler utilities
• Model structs for future API versions

Timeline Estimate

• Bulletins: 30 minutes
• Users/Auth: 45 minutes
• Bible Verses: 20 minutes
• Schedule: 20 minutes
• Config: 15 minutes
• Total: ~2.5 hours

Success Criteria

1. All database functions showing "unused" warnings are eliminated
2. Application builds and runs without breaking changes
3. API endpoints continue to work exactly as before
4. Service layer properly centralizes business logic
5. Handlers are thin and focused on HTTP concerns only