Implement Task Management API with FastAPI and SQLite

README.md

@@ -1,3 +1,91 @@
-# FastAPI Application
+# Task Management API
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A simple task management API built with FastAPI and SQLite.
+
+## Features
+
+- Create, read, update, and delete tasks
+- Mark tasks as completed
+- Filter tasks by completion status and priority
+- Set due dates for tasks
+- Health check endpoint
+
+## Tech Stack
+
+- Python 3.9+
+- FastAPI for API development
+- SQLAlchemy for ORM
+- Alembic for database migrations
+- SQLite for database storage
+- Pydantic for data validation
+- Uvicorn for ASGI server
+
+## Project Structure
+
+```
+.
+├── app/                        # Application package
+│   ├── api/                    # API endpoints
+│   │   └── routes/             # API route definitions
+│   ├── core/                   # Core configuration
+│   ├── db/                     # Database configurations
+│   ├── models/                 # SQLAlchemy models
+│   └── schemas/                # Pydantic schemas
+├── migrations/                 # Alembic migration scripts
+├── alembic.ini                 # Alembic configuration
+├── main.py                     # Entry point for the application
+└── requirements.txt            # Dependencies
+```
+
+## Getting Started
+
+### Prerequisites
+
+- Python 3.9+
+- SQLite
+
+### Installation
+
+1. Clone the repository
+2. Install dependencies:
+   ```
+   pip install -r requirements.txt
+   ```
+3. Run the application:
+   ```
+   uvicorn main:app --reload
+   ```
+
+## API Documentation
+
+Once the application is running, you can access the API documentation at:
+
+- Swagger UI: http://localhost:8000/docs
+- ReDoc: http://localhost:8000/redoc
+
+## API Endpoints
+
+### Health Check
+
+- `GET /health` - Check if the API is running
+
+### Task Management
+
+- `GET /api/tasks` - List all tasks
+- `POST /api/tasks` - Create a new task
+- `GET /api/tasks/{task_id}` - Get a specific task
+- `PUT /api/tasks/{task_id}` - Update a task
+- `DELETE /api/tasks/{task_id}` - Delete a task
+- `POST /api/tasks/{task_id}/complete` - Mark a task as completed
+
+## Task Model
+
+- `id`: Unique identifier
+- `title`: Title of the task
+- `description`: Optional description
+- `is_completed`: Task completion status
+- `priority`: Task priority (1=Low, 2=Medium, 3=High)
+- `created_at`: Creation timestamp
+- `updated_at`: Last update timestamp
+- `completed_at`: Completion timestamp (if completed)
+- `due_date`: Optional due date

alembic.ini

@@ -0,0 +1,86 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = migrations
+
+# template used to generate migration files
+# file_template = %%(rev)s_%%(slug)s
+
+# timezone to use when rendering the date
+# within the migration file as well as the filename.
+# string value is passed to dateutil.tz.gettz()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+# truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; this defaults
+# to migrations/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path
+# version_locations = %(here)s/bar %(here)s/bat migrations/versions
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+sqlalchemy.url = sqlite:////app/storage/db/db.sqlite
+# Use absolute path as instructed
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks=black
+# black.type=console_scripts
+# black.entrypoint=black
+# black.options=-l 79
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

app/api/routes/__init__.py

@@ -0,0 +1,7 @@
+from fastapi import APIRouter
+
+from app.api.routes import tasks
+
+router = APIRouter(prefix="/api")
+
+router.include_router(tasks.router, prefix="/tasks", tags=["Tasks"])

app/api/routes/tasks.py

@@ -0,0 +1,136 @@
+from datetime import datetime
+from typing import List, Optional
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.orm import Session
+
+from app.db.session import get_db
+from app.models.task import Task
+from app.schemas.task import TaskCreate, TaskUpdate, TaskResponse, PriorityEnum
+
+router = APIRouter()
+
+
+@router.post("", response_model=TaskResponse, status_code=status.HTTP_201_CREATED)
+def create_task(*, db: Session = Depends(get_db), task_in: TaskCreate):
+    """Create a new task"""
+    db_task = Task(
+        title=task_in.title,
+        description=task_in.description,
+        priority=task_in.priority,
+        due_date=task_in.due_date
+    )
+    db.add(db_task)
+    db.commit()
+    db.refresh(db_task)
+    return db_task
+
+
+@router.get("", response_model=List[TaskResponse])
+def read_tasks(
+    *,
+    db: Session = Depends(get_db),
+    skip: int = 0,
+    limit: int = 100,
+    is_completed: Optional[bool] = None,
+    priority: Optional[PriorityEnum] = None
+):
+    """
+    Retrieve tasks with optional filtering
+    """
+    query = db.query(Task)
+    
+    # Apply filters if provided
+    if is_completed is not None:
+        query = query.filter(Task.is_completed == is_completed)
+    
+    if priority is not None:
+        query = query.filter(Task.priority == priority)
+    
+    # Apply pagination
+    query = query.offset(skip).limit(limit)
+    
+    # Order by creation date (newest first)
+    query = query.order_by(Task.created_at.desc())
+    
+    return query.all()
+
+
+@router.get("/{task_id}", response_model=TaskResponse)
+def read_task(*, db: Session = Depends(get_db), task_id: int):
+    """Get a specific task by ID"""
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if not task:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Task not found"
+        )
+    return task
+
+
+@router.put("/{task_id}", response_model=TaskResponse)
+def update_task(
+    *, 
+    db: Session = Depends(get_db), 
+    task_id: int, 
+    task_in: TaskUpdate
+):
+    """Update a task"""
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if not task:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Task not found"
+        )
+    
+    update_data = task_in.model_dump(exclude_unset=True)
+    
+    # If task is being marked as completed, set the completed_at timestamp
+    if "is_completed" in update_data and update_data["is_completed"] and not task.is_completed:
+        update_data["completed_at"] = datetime.utcnow()
+    
+    # Reset completed_at if task is being marked as not completed
+    if "is_completed" in update_data and not update_data["is_completed"] and task.is_completed:
+        update_data["completed_at"] = None
+    
+    for field, value in update_data.items():
+        setattr(task, field, value)
+    
+    db.add(task)
+    db.commit()
+    db.refresh(task)
+    return task
+
+
+@router.delete("/{task_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None)
+def delete_task(*, db: Session = Depends(get_db), task_id: int):
+    """Delete a task"""
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if not task:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Task not found"
+        )
+    
+    db.delete(task)
+    db.commit()
+    return None
+
+
+@router.post("/{task_id}/complete", response_model=TaskResponse)
+def mark_task_as_completed(*, db: Session = Depends(get_db), task_id: int):
+    """Mark a task as completed"""
+    task = db.query(Task).filter(Task.id == task_id).first()
+    if not task:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail="Task not found"
+        )
+    
+    # Only update if the task is not already completed
+    if not task.is_completed:
+        task.mark_as_completed()
+        db.add(task)
+        db.commit()
+        db.refresh(task)
+    
+    return task

app/core/config.py

@@ -0,0 +1,33 @@
+from pathlib import Path
+from pydantic_settings import BaseSettings
+from typing import Optional
+
+
+class Settings(BaseSettings):
+    # Application settings
+    PROJECT_NAME: str = "Task Management API"
+    PROJECT_DESCRIPTION: str = "A simple task management API using FastAPI and SQLite"
+    VERSION: str = "0.1.0"
+    API_PREFIX: str = "/api"
+
+    # Database settings
+    DB_DIR: Path = Path("/app") / "storage" / "db"
+    SQLALCHEMY_DATABASE_URL: Optional[str] = None
+
+    class Config:
+        env_file = ".env"
+        env_file_encoding = "utf-8"
+        case_sensitive = True
+
+    def __init__(self, **kwargs):
+        super().__init__(**kwargs)
+
+        # Ensure database directory exists
+        self.DB_DIR.mkdir(parents=True, exist_ok=True)
+
+        # Set database URL if not provided
+        if not self.SQLALCHEMY_DATABASE_URL:
+            self.SQLALCHEMY_DATABASE_URL = f"sqlite:///{self.DB_DIR}/db.sqlite"
+
+
+settings = Settings()

app/db/base.py

@@ -0,0 +1,2 @@
+# Import all models here for Alembic migrations
+from app.models.task import Task  # noqa

app/db/base_class.py

@@ -0,0 +1,14 @@
+from typing import Any
+
+from sqlalchemy.ext.declarative import declared_attr
+from sqlalchemy.orm import DeclarativeBase
+
+
+class Base(DeclarativeBase):
+    id: Any
+    __name__: str
+
+    # Generate __tablename__ automatically
+    @declared_attr
+    def __tablename__(cls) -> str:
+        return cls.__name__.lower()

app/db/session.py

@@ -0,0 +1,22 @@
+from sqlalchemy import create_engine
+from sqlalchemy.orm import sessionmaker
+
+from app.core.config import settings
+
+# Create SQLAlchemy engine
+engine = create_engine(
+    settings.SQLALCHEMY_DATABASE_URL,
+    connect_args={"check_same_thread": False}  # Only needed for SQLite
+)
+
+# Create session factory
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+
+def get_db():
+    """Dependency for getting the database session"""
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/models/task.py

@@ -0,0 +1,30 @@
+from datetime import datetime
+from sqlalchemy import Boolean, Column, DateTime, Integer, String, Text
+from sqlalchemy.sql import func
+
+from app.db.base_class import Base
+
+
+class Task(Base):
+    """Task model representing a to-do item"""
+    
+    id = Column(Integer, primary_key=True, index=True)
+    title = Column(String(255), nullable=False, index=True)
+    description = Column(Text, nullable=True)
+    is_completed = Column(Boolean, default=False)
+    
+    # Priority: 1 (Low), 2 (Medium), 3 (High)
+    priority = Column(Integer, default=2)
+    
+    # Audit timestamp fields
+    created_at = Column(DateTime, default=func.now(), nullable=False)
+    updated_at = Column(DateTime, default=func.now(), onupdate=func.now(), nullable=False)
+    completed_at = Column(DateTime, nullable=True)
+    
+    # Optional due date
+    due_date = Column(DateTime, nullable=True)
+    
+    def mark_as_completed(self) -> None:
+        """Mark the task as completed and set the completion timestamp"""
+        self.is_completed = True
+        self.completed_at = datetime.utcnow()

app/schemas/__init__.py

@@ -0,0 +1,3 @@
+from app.schemas.task import TaskCreate, TaskUpdate, TaskInDB, TaskResponse, PriorityEnum
+
+__all__ = ["TaskCreate", "TaskUpdate", "TaskInDB", "TaskResponse", "PriorityEnum"]

app/schemas/task.py

@@ -0,0 +1,45 @@
+from datetime import datetime
+from enum import Enum
+from typing import Optional
+from pydantic import BaseModel, Field
+
+
+class PriorityEnum(int, Enum):
+    LOW = 1
+    MEDIUM = 2
+    HIGH = 3
+
+
+class TaskBase(BaseModel):
+    title: str = Field(..., min_length=1, max_length=255, description="Title of the task")
+    description: Optional[str] = Field(None, description="Detailed description of the task")
+    priority: PriorityEnum = Field(PriorityEnum.MEDIUM, description="Priority level of the task")
+    due_date: Optional[datetime] = Field(None, description="Due date for the task")
+
+
+class TaskCreate(TaskBase):
+    pass
+
+
+class TaskUpdate(BaseModel):
+    title: Optional[str] = Field(None, min_length=1, max_length=255)
+    description: Optional[str] = None
+    is_completed: Optional[bool] = None
+    priority: Optional[PriorityEnum] = None
+    due_date: Optional[datetime] = None
+
+
+class TaskInDB(TaskBase):
+    id: int
+    is_completed: bool
+    created_at: datetime
+    updated_at: datetime
+    completed_at: Optional[datetime] = None
+
+    class Config:
+        from_attributes = True
+
+
+class TaskResponse(TaskInDB):
+    """Task schema for response"""
+    pass

main.py

@@ -0,0 +1,42 @@
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.routes import router as api_router
+from app.core.config import settings
+
+def create_app() -> FastAPI:
+    app = FastAPI(
+        title=settings.PROJECT_NAME,
+        description=settings.PROJECT_DESCRIPTION,
+        version=settings.VERSION,
+        docs_url="/docs",
+        redoc_url="/redoc",
+    )
+
+    # Set all CORS enabled origins
+    app.add_middleware(
+        CORSMiddleware,
+        allow_origins=["*"],
+        allow_credentials=True,
+        allow_methods=["*"],
+        allow_headers=["*"],
+    )
+
+    # Include routers
+    app.include_router(api_router)
+
+    return app
+
+
+app = create_app()
+
+
+@app.get("/health", tags=["Health"])
+def health_check():
+    return {"status": "healthy"}
+
+
+if __name__ == "__main__":
+    import uvicorn
+
+    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)

migrations/env.py

@@ -0,0 +1,82 @@
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+from app.db.base import Base  # noqa
+target_metadata = Base.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+
+
+def run_migrations_offline():
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online():
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    with connectable.connect() as connection:
+        # Configure for SQLite to support column and table alterations
+        is_sqlite = connection.dialect.name == "sqlite"
+        
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            # Enable SQLite 'batch mode' for alterations
+            render_as_batch=is_sqlite,
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

migrations/script.py.mako

@@ -0,0 +1,24 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+branch_labels = ${repr(branch_labels)}
+depends_on = ${repr(depends_on)}
+
+
+def upgrade():
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade():
+    ${downgrades if downgrades else "pass"}

migrations/versions/202308201234_create_task_table.py

@@ -0,0 +1,40 @@
+"""create task table
+
+Revision ID: 202308201234
+Revises: 
+Create Date: 2023-08-20 12:34:56.789012
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '202308201234'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.create_table(
+        'task',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('title', sa.String(length=255), nullable=False),
+        sa.Column('description', sa.Text(), nullable=True),
+        sa.Column('is_completed', sa.Boolean(), nullable=False, default=False),
+        sa.Column('priority', sa.Integer(), nullable=False, default=2),
+        sa.Column('created_at', sa.DateTime(), nullable=False, server_default=sa.func.now()),
+        sa.Column('updated_at', sa.DateTime(), nullable=False, server_default=sa.func.now(), onupdate=sa.func.now()),
+        sa.Column('completed_at', sa.DateTime(), nullable=True),
+        sa.Column('due_date', sa.DateTime(), nullable=True),
+        sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_task_id'), 'task', ['id'], unique=False)
+    op.create_index(op.f('ix_task_title'), 'task', ['title'], unique=False)
+
+
+def downgrade():
+    op.drop_index(op.f('ix_task_title'), table_name='task')
+    op.drop_index(op.f('ix_task_id'), table_name='task')
+    op.drop_table('task')

requirements.txt

@@ -0,0 +1,8 @@
+fastapi>=0.103.1,<0.104.0
+uvicorn>=0.23.2,<0.24.0
+sqlalchemy>=2.0.20,<2.1.0
+alembic>=1.12.0,<1.13.0
+pydantic>=2.3.0,<2.4.0
+python-multipart>=0.0.6,<0.1.0
+python-dotenv>=1.0.0,<1.1.0
+ruff>=0.0.287,<0.1.0