Add sys import to test files and remove obsolete integration tests

- Add sys import to 29 test files across agent-coordinator, blockchain-event-bridge, blockchain-node, and coordinator-api
- Remove apps/blockchain-event-bridge/tests/test_integration.py (obsolete bridge integration tests)
- Remove apps/coordinator-api/tests/test_integration.py (obsolete API integration tests)
- Implement GPU registration in marketplace_gpu.py with GPURegistry model persistence

apps/plugin-analytics/tests/test_edge_cases_plugin_analytics.py

@@ -0,0 +1,168 @@
+"""Edge case and error handling tests for plugin analytics service"""
+
+import pytest
+import sys
+import sys
+from pathlib import Path
+from fastapi.testclient import TestClient
+from datetime import datetime
+
+
+from main import app, PluginUsage, PluginPerformance, PluginRating, PluginEvent, plugin_usage_data, plugin_performance_data, plugin_ratings, plugin_events
+
+
+@pytest.fixture(autouse=True)
+def reset_state():
+    """Reset global state before each test"""
+    plugin_usage_data.clear()
+    plugin_performance_data.clear()
+    plugin_ratings.clear()
+    plugin_events.clear()
+    yield
+    plugin_usage_data.clear()
+    plugin_performance_data.clear()
+    plugin_ratings.clear()
+    plugin_events.clear()
+
+
+@pytest.mark.unit
+def test_plugin_usage_empty_plugin_id():
+    """Test PluginUsage with empty plugin_id"""
+    usage = PluginUsage(
+        plugin_id="",
+        user_id="user_123",
+        action="install",
+        timestamp=datetime.utcnow()
+    )
+    assert usage.plugin_id == ""
+
+
+@pytest.mark.unit
+def test_plugin_performance_negative_values():
+    """Test PluginPerformance with negative values"""
+    perf = PluginPerformance(
+        plugin_id="plugin_123",
+        version="1.0.0",
+        cpu_usage=-10.0,
+        memory_usage=-5.0,
+        response_time=-0.1,
+        error_rate=-0.01,
+        uptime=-50.0,
+        timestamp=datetime.utcnow()
+    )
+    assert perf.cpu_usage == -10.0
+    assert perf.memory_usage == -5.0
+
+
+@pytest.mark.unit
+def test_plugin_rating_out_of_range():
+    """Test PluginRating with out of range rating"""
+    rating = PluginRating(
+        plugin_id="plugin_123",
+        user_id="user_123",
+        rating=10,
+        timestamp=datetime.utcnow()
+    )
+    assert rating.rating == 10
+
+
+@pytest.mark.unit
+def test_plugin_rating_zero():
+    """Test PluginRating with zero rating"""
+    rating = PluginRating(
+        plugin_id="plugin_123",
+        user_id="user_123",
+        rating=0,
+        timestamp=datetime.utcnow()
+    )
+    assert rating.rating == 0
+
+
+@pytest.mark.integration
+def test_get_plugin_usage_no_data():
+    """Test getting plugin usage when no data exists"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/usage/nonexistent")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_records"] == 0
+
+
+@pytest.mark.integration
+def test_get_plugin_performance_no_data():
+    """Test getting plugin performance when no data exists"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/performance/nonexistent")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_records"] == 0
+
+
+@pytest.mark.integration
+def test_get_plugin_ratings_no_data():
+    """Test getting plugin ratings when no data exists"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/ratings/nonexistent")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_ratings"] == 0
+
+
+@pytest.mark.integration
+def test_dashboard_with_no_data():
+    """Test dashboard with no data"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/dashboard")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["dashboard"]["overview"]["total_plugins"] == 0
+
+
+@pytest.mark.integration
+def test_record_multiple_usage_events():
+    """Test recording multiple usage events for same plugin"""
+    client = TestClient(app)
+    
+    for i in range(5):
+        usage = PluginUsage(
+            plugin_id="plugin_123",
+            user_id=f"user_{i}",
+            action="use",
+            timestamp=datetime.utcnow()
+        )
+        client.post("/api/v1/analytics/usage", json=usage.model_dump(mode='json'))
+    
+    response = client.get("/api/v1/analytics/usage/plugin_123")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["total_records"] == 5
+
+
+@pytest.mark.integration
+def test_usage_trends_days_parameter():
+    """Test usage trends with custom days parameter"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/trends?days=7")
+    assert response.status_code == 200
+    data = response.json()
+    assert "trends" in data
+
+
+@pytest.mark.integration
+def test_get_plugin_usage_days_parameter():
+    """Test getting plugin usage with custom days parameter"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/usage/plugin_123?days=7")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["period_days"] == 7
+
+
+@pytest.mark.integration
+def test_get_plugin_performance_hours_parameter():
+    """Test getting plugin performance with custom hours parameter"""
+    client = TestClient(app)
+    response = client.get("/api/v1/analytics/performance/plugin_123?hours=12")
+    assert response.status_code == 200
+    data = response.json()
+    assert data["period_hours"] == 12