feat(docker): add flexible LLM provider configuration

- Support LLM_PROVIDER env var to override default provider (openai/gpt-4o-mini)
- Add optional 'provider' parameter to API endpoints for per-request overrides
- Implement provider validation to ensure API keys exist
- Update documentation and examples with new configuration options

Closes the need to hardcode providers in config.yml

tests/test_docker_api_with_llm_provider.py

@@ -0,0 +1,122 @@
+#!/usr/bin/env python3
+"""Test script to verify Docker API with LLM provider configuration."""
+
+import requests
+import json
+import time
+
+BASE_URL = "http://localhost:11235"
+
+def test_health():
+    """Test health endpoint."""
+    print("1. Testing health endpoint...")
+    response = requests.get(f"{BASE_URL}/health")
+    print(f"   Status: {response.status_code}")
+    print(f"   Response: {response.json()}")
+    print()
+
+def test_schema():
+    """Test schema endpoint to see configuration."""
+    print("2. Testing schema endpoint...")
+    response = requests.get(f"{BASE_URL}/schema")
+    print(f"   Status: {response.status_code}")
+    # Print only browser config to keep output concise
+    print(f"   Browser config keys: {list(response.json().get('browser', {}).keys())[:5]}...")
+    print()
+
+def test_markdown_with_llm_filter():
+    """Test markdown endpoint with LLM filter (should use configured provider)."""
+    print("3. Testing markdown endpoint with LLM filter...")
+    print("   This should use the Groq provider from LLM_PROVIDER env var")
+    
+    # Note: This will fail with dummy API keys, but we can see if it tries to use Groq
+    payload = {
+        "url": "https://httpbin.org/html",
+        "f": "llm",
+        "q": "Extract the main content"
+    }
+    
+    response = requests.post(f"{BASE_URL}/md", json=payload)
+    print(f"   Status: {response.status_code}")
+    
+    if response.status_code != 200:
+        print(f"   Error: {response.text[:200]}...")
+    else:
+        print(f"   Success! Markdown length: {len(response.json().get('markdown', ''))} chars")
+    print()
+
+def test_markdown_with_provider_override():
+    """Test markdown endpoint with provider override in request."""
+    print("4. Testing markdown endpoint with provider override...")
+    print("   This should use OpenAI provider from request parameter")
+    
+    payload = {
+        "url": "https://httpbin.org/html",
+        "f": "llm",
+        "q": "Extract the main content",
+        "provider": "openai/gpt-4"  # Override to use OpenAI
+    }
+    
+    response = requests.post(f"{BASE_URL}/md", json=payload)
+    print(f"   Status: {response.status_code}")
+    
+    if response.status_code != 200:
+        print(f"   Error: {response.text[:200]}...")
+    else:
+        print(f"   Success! Markdown length: {len(response.json().get('markdown', ''))} chars")
+    print()
+
+def test_simple_crawl():
+    """Test simple crawl without LLM."""
+    print("5. Testing simple crawl (no LLM required)...")
+    
+    payload = {
+        "urls": ["https://httpbin.org/html"],
+        "browser_config": {
+            "type": "BrowserConfig",
+            "params": {"headless": True}
+        },
+        "crawler_config": {
+            "type": "CrawlerRunConfig",
+            "params": {"cache_mode": "bypass"}
+        }
+    }
+    
+    response = requests.post(f"{BASE_URL}/crawl", json=payload)
+    print(f"   Status: {response.status_code}")
+    
+    if response.status_code == 200:
+        result = response.json()
+        print(f"   Success: {result.get('success')}")
+        print(f"   Results count: {len(result.get('results', []))}")
+        if result.get('results'):
+            print(f"   First result success: {result['results'][0].get('success')}")
+    else:
+        print(f"   Error: {response.text[:200]}...")
+    print()
+
+def test_playground():
+    """Test if playground is accessible."""
+    print("6. Testing playground interface...")
+    response = requests.get(f"{BASE_URL}/playground")
+    print(f"   Status: {response.status_code}")
+    print(f"   Content-Type: {response.headers.get('content-type')}")
+    print()
+
+if __name__ == "__main__":
+    print("=== Crawl4AI Docker API Tests ===\n")
+    print(f"Testing API at {BASE_URL}\n")
+    
+    # Wait a bit for server to be fully ready
+    time.sleep(2)
+    
+    test_health()
+    test_schema()
+    test_simple_crawl()
+    test_playground()
+    
+    print("\nTesting LLM functionality (these may fail with dummy API keys):\n")
+    test_markdown_with_llm_filter()
+    test_markdown_with_provider_override()
+    
+    print("\nTests completed!")