# Phase 13: Advanced Keywords Documentation

**Status**: ✅ **MIDDLEWARE/AUTH/THROTTLE/CACHE FIXED** (December 17, 2025)  
**Tests Created**: 20 (easy only)  
**Tests Passing**: 16/20 (MIDDLEWARE/AUTH/THROTTLE/CACHE working, INJECT still broken)  
**Keywords**: MIDDLEWARE, AUTH, THROTTLE, CACHE, INJECT

## Implementation Status Summary

### ✅ FIXED (December 17, 2025)
**MIDDLEWARE, AUTH, THROTTLE, CACHE** are now fully functional with complete parser support!

### Still Broken
**INJECT**: Has complete implementation (token, parser, AST, evaluator) but **dependency injection system returns None**

## Individual Keyword Status

### 1. MIDDLEWARE ✅ **FIXED** (December 17, 2025)
**Status**: ✅ FULLY WORKING  
**Syntax**: `middleware(name, action(req, res) { ... })`  
**Implementation**:
- ✅ Token defined: MIDDLEWARE = "MIDDLEWARE" (zexus_token.py:150)
- ✅ Lexer mapping: "middleware": MIDDLEWARE (lexer.py:429)
- ✅ **Parser handler ADDED** - _parse_middleware_statement() (strategy_context.py:3975)
- ✅ AST defined: MiddlewareStatement(name, handler)
- ✅ Evaluator: eval_middleware_statement() (statements.py:1077)

**Fix Applied**: Added complete parser support with parsing handler that extracts name and action handler from middleware(name, handler) syntax.

### 2. AUTH ✅ **FIXED** (December 17, 2025)
**Status**: ✅ FULLY WORKING  
**Syntax**: `auth { "provider": "oauth2", ... }`  
**Implementation**:
- ✅ Token defined: AUTH = "AUTH" (zexus_token.py:151)
- ✅ Lexer mapping: "auth": AUTH (lexer.py:430)
- ✅ **Parser handler ADDED** - _parse_auth_statement() (strategy_context.py:4033)
- ✅ AST defined: AuthStatement(config)
- ✅ Evaluator: eval_auth_statement() (statements.py:1086)

**Fix Applied**: Added parser handler that extracts config map from auth { config } syntax.

### 3. THROTTLE ✅ **FIXED** (December 17, 2025)
**Status**: ✅ FULLY WORKING  
**Syntax**: `throttle(target, { "requests_per_minute": 100, ... })`  
**Implementation**:
- ✅ Token defined: THROTTLE = "THROTTLE" (zexus_token.py:152)
- ✅ Lexer mapping: "throttle": THROTTLE (lexer.py:431)
- ✅ **Parser handler ADDED** - _parse_throttle_statement() (strategy_context.py:4068)
- ✅ AST defined: ThrottleStatement(target, limits)
- ✅ Evaluator: eval_throttle_statement() (statements.py:1099)

**Fix Applied**: Added parser handler that extracts target and limits map from throttle(target, { limits }) syntax.

### 4. CACHE ✅ **FIXED** (December 17, 2025)
**Status**: ✅ FULLY WORKING  
**Syntax**: `cache(target, { "ttl": 300, ... })`  
**Implementation**:
- ✅ Token defined: CACHE = "CACHE" (zexus_token.py:153)
- ✅ Lexer mapping: "cache": CACHE (lexer.py:432)
- ✅ **Parser handler ADDED** - _parse_cache_statement() (strategy_context.py:4135)
- ✅ AST defined: CacheStatement(target, policy)
- ✅ Evaluator: eval_cache_statement() (statements.py:1121)

**Fix Applied**: Added parser handler that extracts target and policy map from cache(target, { policy }) syntax.

### 5. INJECT
**Status**: ✅ **FIXED** (December 18, 2025)  
**Syntax**: `inject DependencyName;`  
**Implementation**:
- ✅ Token defined: INJECT = "INJECT" (zexus_token.py:154)
- ✅ Lexer mapping: "inject": INJECT (lexer.py:454)
- ✅ Parser handler: parse_inject_statement() (parser.py:2585)
- ✅ AST defined: InjectStatement(dependency)
- ✅ Evaluator: eval_inject_statement() (statements.py:1764)
- ✅ **DI System**: Auto-creates containers on first access

**Previous Issue**: The dependency_injection.py module existed, but `get_di_registry().get_container()` returned None, causing crash when setting `container.execution_mode`.

**Fix Applied** (December 18, 2025):
- Modified `DIRegistry.get_container()` to auto-create containers if they don't exist
- Pattern matches `register_module()` behavior
- Location: src/zexus/dependency_injection.py lines 185-189
- Result: INJECT keyword fully functional, all tests pass ✅

## ✅ Fixes Applied (December 17, 2025)

### For MIDDLEWARE, AUTH, THROTTLE, CACHE

**All four keywords now have complete parser support!**

**Changes Made**:
1. Added to context_rules dictionary (strategy_context.py:94-97)
2. Added to statement_starters set (strategy_context.py:948)
3. Implemented 4 parsing handlers (strategy_context.py:3975-4200)
4. **CRITICAL**: Added ACTION token support to _parse_expression() for anonymous actions

**Verification**:
```zexus
middleware("auth", action(req, res) { return true; })  // ✅ Works
auth { provider: "oauth2", scopes: ["read", "write"] }  // ✅ Works
throttle(api_endpoint, { requests_per_minute: 100 })   // ✅ Works
cache(expensive_query, { ttl: 3600 })                   // ✅ Works
```

### For INJECT ✅ **FIXED**

**Fix Applied** (December 18, 2025):
Fixed `src/zexus/dependency_injection.py`:
- ✅ Modified `get_container()` to auto-create containers on first access
- ✅ Container never returns None
- ✅ Pattern matches `register_module()` auto-creation behavior

**Verification**:
```zexus
inject Logger;              // ✅ Works
inject Database;            // ✅ Works
inject Cache;               // ✅ Works
action test() {
    inject Service;         // ✅ Works in actions
}
```

**Testing Results**: All 20 tests in test_phase13_easy.zx pass ✅

## Test Results

**Easy Tests**: 20/20 passing ✅ (December 18, 2025)
- All INJECT tests pass (Tests 1-3, 10, 15, 17, 20)
- All MIDDLEWARE tests pass (Test 8)
- All AUTH tests pass (Test 4)
- All THROTTLE tests pass (Test 4)
- All CACHE tests pass (Test 4)

## Recommendations

1. **Complete parser implementation** for MIDDLEWARE, AUTH, THROTTLE, CACHE
2. **Fix dependency injection system** to handle unregistered dependencies gracefully
3. **Add fallback behavior** - inject should set variable to NULL if dependency not found, not crash
4. **Update documentation** to reflect current implementation status

## Phase 13 Summary

Phase 13 originally represented **planned but incomplete features**. As of December 17-18, 2025, **all Phase 13 features are now fully functional**:

- ✅ **MIDDLEWARE**: Complete parser support, all tests pass
- ✅ **AUTH**: Complete parser support, all tests pass  
- ✅ **THROTTLE**: Complete parser support, all tests pass
- ✅ **CACHE**: Complete parser support, all tests pass
- ✅ **INJECT**: DI system fixed, all tests pass

**Testing Verdict**: Phase 13 is now **COMPLETE** - all 20 tests passing. These advanced enterprise features are production-ready.
