Comprehensive structured logging has been implemented for the Gemini API integration to track all analysis requests, performance metrics, errors, and operational events.
A custom logger utility has been created with four log levels:
- INFO: Normal operational events
- WARN: Recoverable issues and warnings
- ERROR: Failures that prevent normal operation
- PERFORMANCE: Operation timing and metrics
All logs are output as structured JSON with timestamps and contextual metadata.
- Request start with file metadata (name, type, size)
- Unique request ID for tracing
- File type detection results
- Analysis routing decisions
- Performance logs for every analysis operation
- Duration in milliseconds
- Success/failure status
- Request context (file name, type, etc.)
- All errors logged with full context
- Error messages and stack traces captured
- Retry attempts tracked with backoff delays
- Fallback responses logged with reasons
- Retryable vs non-retryable error classification
logCacheOperation()utility function created- Tracks cache hits and misses
- Includes cache key and metadata
- Ready to be integrated when caching is implemented
logRateLimitCheck()utility function created- Tracks rate limit checks and violations
- Includes username, current count, limit, and remaining quota
- Ready to be integrated when rate limiting is implemented
- Request Tracing: Each request gets a unique ID for end-to-end tracking
- Structured Data: All logs are JSON-formatted for easy parsing
- Rich Context: Logs include relevant metadata (file names, sizes, durations, etc.)
- Error Details: Full error messages and stack traces captured
- Performance Metrics: Response times tracked for all operations
- Retry Tracking: Retry attempts and backoff delays logged
- Fallback Monitoring: Fallback responses tracked with reasons
{
"timestamp": "2024-10-29T12:34:56.789Z",
"level": "INFO",
"message": "Starting document analysis",
"requestId": "req_1698582896789_abc123",
"fileName": "receipt.jpg",
"fileType": "image/jpeg",
"dataLength": 45678
}{
"timestamp": "2024-10-29T12:34:57.234Z",
"level": "PERFORMANCE",
"operation": "Document analysis completed",
"durationMs": 445,
"requestId": "req_1698582896789_abc123",
"fileName": "receipt.jpg",
"fileType": "image",
"success": true
}{
"timestamp": "2024-10-29T12:35:00.123Z",
"level": "ERROR",
"message": "Image analysis failed",
"error": "API timeout",
"retryCount": 0,
"fileName": "invoice.pdf",
"fileSize": 123456
}src/server/ai/gemini.ts: Added structured logger and comprehensive logging throughout
src/server/ai/LOGGING.md: Comprehensive logging documentationGEMINI_LOGGING_SUMMARY.md: This summary document
✅ All key events logged
- Client initialization
- Analysis requests (start and completion)
- File type detection
- Response parsing
- Retries and backoffs
- Fallback responses
✅ Logs include relevant context
- Request IDs for tracing
- File metadata (name, type, size)
- Timestamps (ISO 8601 format)
- Error messages and stack traces
- Performance metrics (duration)
- Success/failure status
✅ Performance metrics tracked
- Analysis duration for every request
- Success/failure status
- Request metadata
- Separate PERFORMANCE log level
✅ Error patterns identifiable
- Structured error logging with full context
- Error classification (retryable vs non-retryable)
- Retry attempts tracked
- Fallback triggers logged
- Stack traces captured
The implemented logging enables:
- Success Rate Monitoring: Track ratio of successful vs failed analyses
- Performance Analysis: Monitor average response times and identify slow requests
- Error Pattern Detection: Identify common failure modes and error types
- Retry Analysis: Track how often retries are needed and their success rate
- Fallback Tracking: Monitor how often fallback responses are used
- Cache Efficiency (when implemented): Track cache hit/miss rates
- Rate Limit Monitoring (when implemented): Track usage patterns and violations
The logging system is ready to integrate with:
- Log aggregation tools (Splunk, ELK Stack)
- Monitoring platforms (CloudWatch, Datadog)
- Custom analytics scripts (jq, grep)
- Real-time alerting systems
When implementing caching (Task 2.3) and rate limiting (Task 2.2):
-
Import the utility functions:
import { logCacheOperation, logRateLimitCheck } from './ai/gemini';
-
Call them at appropriate points:
// In caching layer logCacheOperation(hit, cacheKey, { fileName, fileType }); // In rate limiting layer logRateLimitCheck(username, currentCount, limit, exceeded);
Build verification completed successfully:
- ✅ TypeScript compilation passed
- ✅ No diagnostics or errors
- ✅ All imports resolved correctly
- ✅ Structured logger working as expected
Comprehensive documentation created in src/server/ai/LOGGING.md covering:
- Log structure and levels
- Key metrics tracked
- Example log entries
- Monitoring and analysis guidance
- Integration with monitoring tools
- Best practices