Added JobRepository and JobServices

src/file-processor/app/services/job_service.py

@@ -0,0 +1,182 @@
+"""
+Service layer for job processing business logic.
+
+This module provides high-level operations for managing processing jobs
+with strict status transition validation and business rules enforcement.
+"""
+
+from typing import Optional
+
+from app.database.repositories.job_repository import JobRepository
+from app.exceptions.job_exceptions import InvalidStatusTransitionError
+from app.models.job import ProcessingJob, ProcessingStatus
+from app.models.types import PyObjectId
+
+
+class JobService:
+  """
+  Service for processing job business logic operations.
+
+  Provides high-level job management with strict status transition
+  validation and business rule enforcement.
+  """
+  
+  def __init__(self, database):
+    """
+    Initialize service with job repository.
+
+    Args:
+        repository: Optional JobRepository instance (creates default if None)
+    """
+    self.db = database
+    self.repository = JobRepository(database)
+  
+  async def initialize(self):
+    await self.repository.initialize()
+    return self
+  
+  async def create_job(self, file_id: PyObjectId, task_id: Optional[str] = None) -> ProcessingJob:
+    """
+    Create a new processing job.
+
+    Args:
+        file_id: Reference to the file document
+        task_id: Optional Celery task UUID
+
+    Returns:
+        The created ProcessingJob
+
+    Raises:
+        JobRepositoryError: If database operation fails
+    """
+    return await self.repository.create_job(file_id, task_id)
+  
+  async def get_job_by_id(self, job_id: PyObjectId) -> ProcessingJob:
+    """
+    Retrieve a job by its ID.
+
+    Args:
+        job_id: The job ObjectId
+
+    Returns:
+        The ProcessingJob document
+
+    Raises:
+        JobNotFoundError: If job doesn't exist
+        JobRepositoryError: If database operation fails
+    """
+    return await self.repository.find_job_by_id(job_id)
+  
+  async def mark_job_as_started(self, job_id: PyObjectId) -> ProcessingJob:
+    """
+    Mark a job as started (PENDING → PROCESSING).
+
+    Args:
+        job_id: The job ObjectId
+
+    Returns:
+        The updated ProcessingJob
+
+    Raises:
+        JobNotFoundError: If job doesn't exist
+        InvalidStatusTransitionError: If job is not in PENDING status
+        JobRepositoryError: If database operation fails
+    """
+    # Get current job to validate transition
+    current_job = await self.repository.find_job_by_id(job_id)
+    
+    # Validate status transition
+    if current_job.status != ProcessingStatus.PENDING:
+      raise InvalidStatusTransitionError(current_job.status, ProcessingStatus.PROCESSING)
+    
+    # Update status
+    return await self.repository.update_job_status(job_id, ProcessingStatus.PROCESSING)
+  
+  async def mark_job_as_completed(self, job_id: PyObjectId) -> ProcessingJob:
+    """
+    Mark a job as completed (PROCESSING → COMPLETED).
+
+    Args:
+        job_id: The job ObjectId
+
+    Returns:
+        The updated ProcessingJob
+
+    Raises:
+        JobNotFoundError: If job doesn't exist
+        InvalidStatusTransitionError: If job is not in PROCESSING status
+        JobRepositoryError: If database operation fails
+    """
+    # Get current job to validate transition
+    current_job = await self.repository.find_job_by_id(job_id)
+    
+    # Validate status transition
+    if current_job.status != ProcessingStatus.PROCESSING:
+      raise InvalidStatusTransitionError(current_job.status, ProcessingStatus.COMPLETED)
+    
+    # Update status
+    return await self.repository.update_job_status(job_id, ProcessingStatus.COMPLETED)
+  
+  async def mark_job_as_failed(
+      self,
+      job_id: PyObjectId,
+      error_message: Optional[str] = None
+  ) -> ProcessingJob:
+    """
+    Mark a job as failed (PROCESSING → FAILED).
+
+    Args:
+        job_id: The job ObjectId
+        error_message: Optional error description
+
+    Returns:
+        The updated ProcessingJob
+
+    Raises:
+        JobNotFoundError: If job doesn't exist
+        InvalidStatusTransitionError: If job is not in PROCESSING status
+        JobRepositoryError: If database operation fails
+    """
+    # Get current job to validate transition
+    current_job = await self.repository.find_job_by_id(job_id)
+    
+    # Validate status transition
+    if current_job.status != ProcessingStatus.PROCESSING:
+      raise InvalidStatusTransitionError(current_job.status, ProcessingStatus.FAILED)
+    
+    # Update status with error message
+    return await self.repository.update_job_status(
+      job_id,
+      ProcessingStatus.FAILED,
+      error_message
+    )
+  
+  async def delete_job(self, job_id: PyObjectId) -> bool:
+    """
+    Delete a job from the database.
+
+    Args:
+        job_id: The job ObjectId
+
+    Returns:
+        True if job was deleted, False if not found
+
+    Raises:
+        JobRepositoryError: If database operation fails
+    """
+    return await self.repository.delete_job(job_id)
+  
+  async def get_jobs_by_status(self, status: ProcessingStatus) -> list[ProcessingJob]:
+    """
+    Retrieve all jobs with a specific status.
+
+    Args:
+        status: The processing status to filter by
+
+    Returns:
+        List of ProcessingJob documents
+
+    Raises:
+        JobRepositoryError: If database operation fails
+    """
+    return await self.repository.get_jobs_by_status(status)