Add GitHub Actions CI/CD pipeline

- Automatically run tests on every push
- Test on Python 3.11 in clean environment
- Verify Docker build succeeds
- Run on main branch pushes and pull requests
- Provides automated quality gate

.github/workflows/test.yml

@@ -0,0 +1,45 @@
+# GitHub Actions Workflow for Sentiment API
+# This runs automatically on every push and pull request
+# Ensures code quality through automated testing
+
+name: Test and Build
+
+# When to run this workflow
+on:
+  push:
+    branches: [ main ]  # Run on pushes to main
+  pull_request:
+    branches: [ main ]  # Run on PRs to main
+
+# Define the jobs to run
+jobs:
+  test:
+    name: Run Tests
+    runs-on: ubuntu-latest  # Use Ubuntu Linux environment
+    
+    steps:
+      # Step 1: Get the code from repository
+      - name: Checkout code
+        uses: actions/checkout@v4
+      
+      # Step 2: Set up Python environment
+      - name: Set up Python 3.11
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+      
+      # Step 3: Install dependencies
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install -r requirements.txt
+      
+      # Step 4: Run tests with pytest
+      - name: Run tests
+        run: |
+          pytest tests/ -v --tb=short
+      
+      # Step 5: Verify Docker build works
+      - name: Test Docker build
+        run: |
+          docker build -t sentiment-api:test .

requirements.txt

@@ -4,4 +4,8 @@ transformers==4.46.3
 torch==2.5.1
 pydantic==2.10.3
 pytest==8.3.4
-httpx==0.28.1
+httpx==0.28.1
+
+# Testing
+pytest==8.3.4
+pytest-cov==6.0.0

tests/test_api.py

@@ -0,0 +1,280 @@
+"""
+Unit tests for sentiment analysis API
+
+These tests verify:
+- All endpoints work correctly
+- Sentiment analysis returns expected results
+- Input validation catches errors
+- Error handling works properly
+"""
+
+from fastapi.testclient import TestClient
+from src.main import app
+import pytest
+
+# Create test client
+client = TestClient(app)
+
+
+# ============================================
+# Health Check Tests
+# ============================================
+
+def test_root_endpoint():
+    """Test the root endpoint returns health status"""
+    response = client.get("/")
+    
+    assert response.status_code == 200
+    data = response.json()
+    assert data["status"] == "healthy"
+    assert data["service"] == "sentiment-api"
+    assert "version" in data
+
+
+def test_health_endpoint():
+    """Test the /health endpoint for Kubernetes"""
+    response = client.get("/health")
+    
+    assert response.status_code == 200
+    assert response.json() == {"status": "ok"}
+
+
+# ============================================
+# Sentiment Analysis Tests
+# ============================================
+
+def test_analyze_positive_sentiment():
+    """Test sentiment analysis with clearly positive text"""
+    response = client.post(
+        "/analyze",
+        json={"text": "I absolutely love this product! It's amazing and wonderful!"}
+    )
+    
+    assert response.status_code == 200
+    data = response.json()
+    
+    # Verify response structure
+    assert "text" in data
+    assert "sentiment" in data
+    assert "confidence" in data
+    assert "processing_time_ms" in data
+    
+    # Verify sentiment detection
+    assert data["sentiment"] == "POSITIVE"
+    assert data["confidence"] > 0.9  # Should be very confident
+    assert data["processing_time_ms"] > 0  # Should take some time
+
+
+def test_analyze_negative_sentiment():
+    """Test sentiment analysis with clearly negative text"""
+    response = client.post(
+        "/analyze",
+        json={"text": "This is terrible, horrible, and awful. I hate it."}
+    )
+    
+    assert response.status_code == 200
+    data = response.json()
+    
+    assert data["sentiment"] == "NEGATIVE"
+    assert data["confidence"] > 0.9
+
+
+def test_analyze_neutral_text():
+    """Test sentiment analysis with neutral text"""
+    response = client.post(
+        "/analyze",
+        json={"text": "The item is blue."}
+    )
+    
+    assert response.status_code == 200
+    data = response.json()
+    
+    # Neutral text might be classified as either POSITIVE or NEGATIVE
+    # with lower confidence
+    assert data["sentiment"] in ["POSITIVE", "NEGATIVE"]
+    assert "confidence" in data
+
+
+# ============================================
+# Input Validation Tests
+# ============================================
+
+def test_empty_text_rejected():
+    """Test that empty text is rejected"""
+    response = client.post(
+        "/analyze",
+        json={"text": ""}
+    )
+    
+    assert response.status_code == 422  # Validation error
+    # FastAPI returns detailed validation errors
+
+
+def test_missing_text_field():
+    """Test that missing text field is rejected"""
+    response = client.post(
+        "/analyze",
+        json={}
+    )
+    
+    assert response.status_code == 422
+
+
+def test_text_too_long():
+    """Test that text exceeding max length is rejected"""
+    long_text = "a" * 513  # Max is 512 characters
+    
+    response = client.post(
+        "/analyze",
+        json={"text": long_text}
+    )
+    
+    assert response.status_code == 422
+
+
+def test_non_string_text():
+    """Test that non-string text is rejected"""
+    response = client.post(
+        "/analyze",
+        json={"text": 12345}  # Number instead of string
+    )
+    
+    assert response.status_code == 422
+
+
+# ============================================
+# Response Format Tests
+# ============================================
+
+def test_response_contains_all_fields():
+    """Test that response has all required fields"""
+    response = client.post(
+        "/analyze",
+        json={"text": "Great product!"}
+    )
+    
+    assert response.status_code == 200
+    data = response.json()
+    
+    # Check all required fields exist
+    required_fields = ["text", "sentiment", "confidence", "processing_time_ms"]
+    for field in required_fields:
+        assert field in data, f"Missing field: {field}"
+
+
+def test_confidence_is_valid_probability():
+    """Test that confidence is between 0 and 1"""
+    response = client.post(
+        "/analyze",
+        json={"text": "Excellent!"}
+    )
+    
+    data = response.json()
+    confidence = data["confidence"]
+    
+    assert 0 <= confidence <= 1, "Confidence must be between 0 and 1"
+
+
+def test_sentiment_is_valid_label():
+    """Test that sentiment is either POSITIVE or NEGATIVE"""
+    response = client.post(
+        "/analyze",
+        json={"text": "Test text"}
+    )
+    
+    data = response.json()
+    sentiment = data["sentiment"]
+    
+    assert sentiment in ["POSITIVE", "NEGATIVE"], "Invalid sentiment label"
+
+
+# ============================================
+# Edge Case Tests
+# ============================================
+
+def test_special_characters():
+    """Test handling of special characters"""
+    response = client.post(
+        "/analyze",
+        json={"text": "Wow!!! This is #amazing 😊 @company"}
+    )
+    
+    assert response.status_code == 200
+    # Should handle emojis and special chars gracefully
+
+
+def test_multiple_languages_english_only():
+    """Test that non-English text still gets processed"""
+    # Note: DistilBERT is trained on English
+    # This test just verifies it doesn't crash
+    response = client.post(
+        "/analyze",
+        json={"text": "Hola mundo"}
+    )
+    
+    assert response.status_code == 200
+    # May not be accurate, but shouldn't crash
+
+
+def test_very_short_text():
+    """Test analysis of very short text"""
+    response = client.post(
+        "/analyze",
+        json={"text": "Good"}
+    )
+    
+    assert response.status_code == 200
+    data = response.json()
+    assert data["sentiment"] == "POSITIVE"
+
+
+def test_maximum_length_text():
+    """Test analysis of text at maximum allowed length"""
+    max_text = "a" * 512  # Exactly at max
+    
+    response = client.post(
+        "/analyze",
+        json={"text": max_text}
+    )
+    
+    assert response.status_code == 200
+
+
+# ============================================
+# Performance Tests
+# ============================================
+
+def test_response_time_reasonable():
+    """Test that response time is reasonable (< 5 seconds)"""
+    import time
+    
+    start = time.time()
+    response = client.post(
+        "/analyze",
+        json={"text": "Test performance"}
+    )
+    elapsed = time.time() - start
+    
+    assert response.status_code == 200
+    assert elapsed < 5.0, f"Response took {elapsed}s, should be < 5s"
+
+
+# ============================================
+# API Documentation Tests
+# ============================================
+
+def test_openapi_docs_available():
+    """Test that API documentation is available"""
+    response = client.get("/docs")
+    assert response.status_code == 200
+
+
+def test_openapi_json_available():
+    """Test that OpenAPI JSON schema is available"""
+    response = client.get("/openapi.json")
+    assert response.status_code == 200
+    
+    schema = response.json()
+    assert "openapi" in schema
+    assert "info" in schema
+    assert "paths" in schema