Introduction

API call fails when client version incompatible with server version. This guide provides step-by-step diagnosis and resolution.

Symptoms

Typical error output:

bash
HTTP 500 Internal Server Error
{"error": "Internal error", "message": "Request failed"}
Check API logs for details

Common Causes

  1. 1.Rate limiting or quota exceeded
  2. 2.Authentication or authorization failure
  3. 3.Network connectivity issues
  4. 4.Server-side error or misconfiguration

Step-by-Step Fix

Step 1: Check Current State

bash
# Test API endpoint
curl -v https://api.example.com/endpoint
# Check API logs
tail -f /var/log/api/error.log
# Verify API health
curl https://api.example.com/health

Step 2: Identify Root Cause

bash
# Test API connectivity
curl -v https://api.example.com/endpoint
# Check authentication
curl -H "Authorization: Bearer <token>" https://api.example.com/verify
# Review logs
tail -f /var/log/api/error.log

Step 3: Apply Primary Fix

```bash # Primary fix curl -X GET "https://api.example.com/endpoint" \ -H "Authorization: Bearer <valid-token>" \ -H "Content-Type: application/json"

# Verify response # Should return 200 OK with expected data ```

Step 4: Apply Alternative Fix

bash
# Alternative: Check configuration
cat /etc/api/config.yaml
# Review authentication
curl -I https://api.example.com/endpoint
# Check logs
grep -i error /var/log/api/*.log

Step 5: Verify the Fix

bash
curl -s -o /dev/null -w "%{http_code}" https://api.example.com/health
# Should return 200

Common Pitfalls

  • Not handling rate limit headers in client code
  • Using expired or invalid authentication tokens
  • Ignoring error response bodies with diagnostic information
  • Not implementing proper retry logic with exponential backoff

Best Practices

  • Implement circuit breaker pattern for API calls
  • Use connection pooling with appropriate timeouts
  • Cache responses when possible to reduce API load
  • Monitor API metrics and set up alerts
  • API Connection Timeout
  • API Authentication Failed
  • API Rate Limit Exceeded
  • API Server Error