Task B12: Implement Celery file processing for CSV uploads

backend/api/projects.py

@@ -19,6 +19,7 @@
 )
 from services.project_service import get_project_service
 from services.storage_service import storage_service
+from tasks.file_processing import process_csv_file
 
 router = APIRouter(prefix="/projects", tags=["projects"])
 project_service = get_project_service()
@@ -277,6 +278,55 @@ async def get_upload_url(
         )
 
 
+@router.post("/{project_id}/process")
+async def trigger_file_processing(
+    project_id: str, user_id: str = Depends(verify_token)
+) -> ApiResponse[Dict[str, str]]:
+    """Trigger CSV file processing for a project"""
+
+    try:
+        user_uuid = uuid.UUID(user_id)
+        project_uuid = uuid.UUID(project_id)
+
+        # Check if project exists and user owns it
+        if not project_service.check_project_ownership(project_uuid, user_uuid):
+            raise HTTPException(status_code=404, detail="Project not found")
+
+        # Get project to check current status
+        project_db = project_service.get_project_by_id(project_uuid)
+        if project_db.status == "ready":
+            raise HTTPException(status_code=400, detail="Project already processed")
+
+        # Check if file exists in storage
+        object_name = f"{user_id}/{project_id}/data.csv"
+        if not storage_service.file_exists(object_name):
+            raise HTTPException(
+                status_code=400, detail="No file uploaded for processing"
+            )
+
+        # Trigger Celery task
+        task = process_csv_file.delay(project_id, user_id)
+
+        return ApiResponse(
+            success=True,
+            data={
+                "message": "File processing started",
+                "task_id": task.id,
+                "project_id": project_id,
+            },
+        )
+
+    except ValueError as e:
+        raise HTTPException(status_code=400, detail=f"Invalid project ID: {str(e)}")
+    except HTTPException:
+        # Re-raise HTTPExceptions without wrapping them
+        raise
+    except Exception as e:
+        raise HTTPException(
+            status_code=500, detail=f"Failed to start file processing: {str(e)}"
+        )
+
+
 @router.get("/{project_id}/status")
 async def get_project_status(
     project_id: str, user_id: str = Depends(verify_token)

backend/services/project_service.py

@@ -133,20 +133,19 @@ def update_project_status(
     def update_project_metadata(
         self,
         project_id: uuid.UUID,
-        csv_filename: str,
         row_count: int,
         column_count: int,
         columns_metadata: list,
+        status: ProjectStatusEnum = ProjectStatusEnum.READY,
     ) -> ProjectInDB:
         """Update project metadata after file processing"""
         return self.update_project(
             project_id,
             ProjectUpdate(
-                csv_filename=csv_filename,
                 row_count=row_count,
                 column_count=column_count,
                 columns_metadata=columns_metadata,
-                status=ProjectStatusEnum.READY,
+                status=status,
             ),
         )
 

backend/tasks/file_processing.py

@@ -1,63 +1,142 @@
 import logging
 import os
+import uuid
+from io import StringIO
+from typing import Any, Dict, List, Optional
 
+import pandas as pd
 from celery import current_task
 
 from celery_app import celery_app
+from services.database_service import get_db_service
+from services.project_service import get_project_service
+from services.storage_service import storage_service
 
 logger = logging.getLogger(__name__)
 
 
 @celery_app.task(bind=True)
-def process_csv_file(self, project_id: str, file_path: str):
+def process_csv_file(self, project_id: str, user_id: str):
     """
-    Process uploaded CSV file - placeholder implementation for Task B2
-    Will be fully implemented in Task B12
+    Process uploaded CSV file for project analysis
     """
     try:
+        project_uuid = uuid.UUID(project_id)
+        user_uuid = uuid.UUID(user_id)
+
         # Update task state
         self.update_state(
             state="PROGRESS",
             meta={"current": 10, "total": 100, "status": "Starting CSV analysis..."},
         )
 
-        logger.info(f"Processing CSV file for project {project_id}: {file_path}")
+        logger.info(f"Processing CSV file for project {project_id}")
 
-        # Simulate processing steps
-        import time
+        # Get project service
+        project_service = get_project_service()
+
+        # Update project status to processing
+        project_service.update_project_status(project_uuid, "processing")
+
+        # Download file from MinIO
+        self.update_state(
+            state="PROGRESS",
+            meta={"current": 20, "total": 100, "status": "Downloading file..."},
+        )
 
-        time.sleep(2)
+        object_name = f"{user_id}/{project_id}/data.csv"
+        file_content = storage_service.download_file(object_name)
 
+        if not file_content:
+            raise Exception("Failed to download file from storage")
+
+        # Parse CSV with pandas
         self.update_state(
             state="PROGRESS",
-            meta={"current": 50, "total": 100, "status": "Analyzing schema..."},
+            meta={"current": 40, "total": 100, "status": "Parsing CSV..."},
         )
 
-        time.sleep(2)
+        try:
+            df = pd.read_csv(StringIO(file_content.decode("utf-8")))
+        except Exception as e:
+            raise Exception(f"Failed to parse CSV: {str(e)}")
 
+        # Analyze schema
         self.update_state(
             state="PROGRESS",
-            meta={"current": 90, "total": 100, "status": "Finalizing..."},
+            meta={"current": 60, "total": 100, "status": "Analyzing schema..."},
+        )
+
+        columns_metadata = []
+        for column in df.columns:
+            col_type = str(df[column].dtype)
+
+            # Determine data type category
+            if "int" in col_type or "float" in col_type:
+                data_type = "number"
+            elif "datetime" in col_type:
+                data_type = "datetime"
+            elif "bool" in col_type:
+                data_type = "boolean"
+            else:
+                data_type = "string"
+
+            # Check for null values
+            nullable = df[column].isnull().any()
+
+            # Get sample values (first 5 non-null values)
+            sample_values = df[column].dropna().head(5).tolist()
+
+            columns_metadata.append(
+                {
+                    "name": column,
+                    "type": data_type,
+                    "nullable": nullable,
+                    "sample_values": sample_values,
+                }
+            )
+
+        # Update project with analysis results
+        self.update_state(
+            state="PROGRESS",
+            meta={"current": 80, "total": 100, "status": "Updating project..."},
+        )
+
+        project_service.update_project_metadata(
+            project_uuid,
+            row_count=len(df),
+            column_count=len(df.columns),
+            columns_metadata=columns_metadata,
+            status="ready",
+        )
+
+        # Final update
+        self.update_state(
+            state="PROGRESS",
+            meta={"current": 100, "total": 100, "status": "Processing complete"},
         )
 
-        # Mock result
         result = {
             "project_id": project_id,
             "status": "completed",
-            "row_count": 1000,
-            "column_count": 10,
-            "columns_metadata": [
-                {"name": "id", "type": "number", "nullable": False},
-                {"name": "name", "type": "string", "nullable": False},
-                {"name": "email", "type": "string", "nullable": True},
-            ],
+            "row_count": len(df),
+            "column_count": len(df.columns),
+            "columns_metadata": columns_metadata,
         }
 
         logger.info(f"Successfully processed CSV for project {project_id}")
         return result
 
     except Exception as exc:
         logger.error(f"Error processing CSV for project {project_id}: {str(exc)}")
+
+        # Update project status to error
+        try:
+            project_service = get_project_service()
+            project_service.update_project_status(project_uuid, "error")
+        except:
+            pass
+
         self.update_state(
             state="FAILURE", meta={"error": str(exc), "project_id": project_id}
         )

backend/tests/test_file_processing.py

@@ -0,0 +1,136 @@
+from io import StringIO
+from unittest.mock import Mock, patch
+
+import pandas as pd
+import pytest
+
+from tasks.file_processing import process_csv_file
+
+
+class TestFileProcessing:
+    """Test Celery file processing tasks"""
+
+    @patch("tasks.file_processing.storage_service")
+    @patch("tasks.file_processing.get_project_service")
+    @patch.object(process_csv_file, "update_state", autospec=True)
+    def test_process_csv_file_success(
+        self, mock_update_state, mock_project_service, mock_storage_service
+    ):
+        """Test successful CSV file processing"""
+        # Mock project service
+        mock_service = Mock()
+        mock_project_service.return_value = mock_service
+
+        # Mock storage service
+        csv_content = """id,name,email,age
+1,John Doe,john@example.com,30
+2,Jane Smith,jane@example.com,25
+3,Bob Johnson,bob@example.com,35"""
+
+        mock_storage_service.download_file.return_value = csv_content.encode("utf-8")
+
+        # Call the task function directly (not through Celery wrapper)
+        result = process_csv_file.run(
+            "00000000-0000-0000-0000-000000000001",
+            "00000000-0000-0000-0000-000000000002",
+        )
+
+        # Verify storage service was called
+        mock_storage_service.download_file.assert_called_once_with(
+            "00000000-0000-0000-0000-000000000002/00000000-0000-0000-0000-000000000001/data.csv"
+        )
+
+        # Verify project service was called
+        mock_service.update_project_status.assert_called()
+        mock_service.update_project_metadata.assert_called()
+
+        # Verify result
+        assert result["project_id"] == "00000000-0000-0000-0000-000000000001"
+        assert result["status"] == "completed"
+        assert result["row_count"] == 3
+        assert result["column_count"] == 4
+
+        # Verify column metadata
+        columns_metadata = result["columns_metadata"]
+        assert len(columns_metadata) == 4
+
+        # Check that columns are detected
+        column_names = [col["name"] for col in columns_metadata]
+        assert "id" in column_names
+        assert "name" in column_names
+        assert "email" in column_names
+        assert "age" in column_names
+
+    @patch("tasks.file_processing.storage_service")
+    @patch("tasks.file_processing.get_project_service")
+    @patch.object(process_csv_file, "update_state", autospec=True)
+    def test_process_csv_file_download_failure(
+        self, mock_update_state, mock_project_service, mock_storage_service
+    ):
+        """Test CSV processing when file download fails"""
+        # Mock project service
+        mock_service = Mock()
+        mock_project_service.return_value = mock_service
+
+        # Mock storage service to return None (download failure)
+        mock_storage_service.download_file.return_value = None
+
+        # Call the task and expect exception
+        with pytest.raises(Exception, match="Failed to download file from storage"):
+            process_csv_file.run(
+                "00000000-0000-0000-0000-000000000001",
+                "00000000-0000-0000-0000-000000000002",
+            )
+
+    @patch("tasks.file_processing.storage_service")
+    @patch("tasks.file_processing.get_project_service")
+    @patch.object(process_csv_file, "update_state", autospec=True)
+    @patch("tasks.file_processing.pd.read_csv")
+    def test_process_csv_file_parse_failure(
+        self,
+        mock_pandas_read_csv,
+        mock_update_state,
+        mock_project_service,
+        mock_storage_service,
+    ):
+        """Test CSV processing when file parsing fails"""
+        # Mock project service
+        mock_service = Mock()
+        mock_project_service.return_value = mock_service
+
+        # Mock storage service to return valid content
+        mock_storage_service.download_file.return_value = b"valid,csv,content"
+
+        # Mock pandas to raise an exception
+        mock_pandas_read_csv.side_effect = Exception("CSV parsing failed")
+
+        # Call the task and expect exception
+        with pytest.raises(Exception, match="Failed to parse CSV"):
+            process_csv_file.run(
+                "00000000-0000-0000-0000-000000000001",
+                "00000000-0000-0000-0000-000000000002",
+            )
+
+    @patch("tasks.file_processing.storage_service")
+    @patch("tasks.file_processing.get_project_service")
+    @patch.object(process_csv_file, "update_state", autospec=True)
+    def test_process_csv_file_error_handling(
+        self, mock_update_state, mock_project_service, mock_storage_service
+    ):
+        """Test error handling in CSV processing"""
+        # Mock project service to raise exception
+        mock_service = Mock()
+        mock_service.update_project_status.side_effect = Exception("Database error")
+        mock_project_service.return_value = mock_service
+
+        # Mock storage service
+        csv_content = """id,name
+1,John Doe"""
+        mock_storage_service.download_file.return_value = csv_content.encode("utf-8")
+
+        # Call the task and expect exception
+        with pytest.raises(Exception, match="Database error"):
+            process_csv_file.run(
+                "00000000-0000-0000-0000-000000000001",
+                "00000000-0000-0000-0000-000000000002",
+            )