Implement Task Manager API with FastAPI and SQLite

README.md

@@ -1,3 +1,130 @@
-# FastAPI Application
+# Task Manager API
 
-This is a FastAPI application bootstrapped by BackendIM, the AI-powered backend generation platform.
+A RESTful API for managing tasks built with FastAPI and SQLite.
+
+## Features
+
+- Create, read, update, and delete tasks
+- Filter tasks by completion status and priority
+- Health check endpoint
+- SQLite database with SQLAlchemy ORM
+- Database migrations with Alembic
+
+## Tech Stack
+
+- **Framework**: FastAPI
+- **Database**: SQLite
+- **ORM**: SQLAlchemy
+- **Migrations**: Alembic
+
+## Project Structure
+
+```
+.
+├── app
+│   ├── api
+│   │   ├── endpoints
+│   │   │   ├── health.py
+│   │   │   └── tasks.py
+│   │   └── api.py
+│   ├── core
+│   ├── db
+│   │   └── database.py
+│   ├── models
+│   │   └── task.py
+│   ├── schemas
+│   │   └── task.py
+│   └── main.py
+├── migrations
+│   ├── versions
+│   │   └── 001_create_tasks_table.py
+│   ├── env.py
+│   └── script.py.mako
+├── storage
+│   └── db
+├── alembic.ini
+├── main.py
+├── README.md
+└── requirements.txt
+```
+
+## Installation
+
+1. Clone the repository:
+
+```bash
+git clone https://github.com/yourusername/taskmanagerapi.git
+cd taskmanagerapi
+```
+
+2. Install dependencies:
+
+```bash
+pip install -r requirements.txt
+```
+
+3. Run database migrations:
+
+```bash
+alembic upgrade head
+```
+
+## Usage
+
+### Running the API
+
+```bash
+# Development with auto-reload
+python main.py
+
+# Or using uvicorn directly
+uvicorn app.main:app --reload
+```
+
+The API will be available at `http://localhost:8000`.
+
+### API Documentation
+
+FastAPI automatically generates interactive API documentation:
+
+- Swagger UI: `http://localhost:8000/docs`
+- ReDoc: `http://localhost:8000/redoc`
+
+## API Endpoints
+
+### Health Check
+
+- `GET /health` - Check API and database health
+
+### Tasks
+
+- `GET /tasks` - List all tasks (with optional filtering)
+- `POST /tasks` - Create a new task
+- `GET /tasks/{task_id}` - Get a specific task
+- `PUT /tasks/{task_id}` - Update a task
+- `DELETE /tasks/{task_id}` - Delete a task
+
+## Task Model
+
+```json
+{
+  "id": 1,
+  "title": "Example Task",
+  "description": "This is an example task",
+  "completed": false,
+  "priority": 1,
+  "due_date": "2023-09-30T00:00:00Z",
+  "created_at": "2023-09-25T15:00:00Z",
+  "updated_at": "2023-09-25T15:00:00Z"
+}
+```
+
+### Priority Levels
+
+- `0`: Low
+- `1`: Medium
+- `2`: High
+
+## License
+
+This project is licensed under the MIT License.

alembic.ini

@@ -0,0 +1,105 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = migrations
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+# file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python-dateutil library that can be
+# installed by adding `alembic[tz]` to the pip requirements
+# 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.
+# The path separator used here should be the separator specified by "version_path_separator" below.
+# version_locations = %(here)s/bar:%(here)s/bat:migrations/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.
+
+# 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
+
+
+[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 REVISION_SCRIPT_FILENAME
+
+# 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/api.py

@@ -0,0 +1,8 @@
+from fastapi import APIRouter
+
+from app.api.endpoints import tasks, health
+
+api_router = APIRouter()
+
+api_router.include_router(health.router, prefix="/health", tags=["health"])
+api_router.include_router(tasks.router, prefix="/tasks", tags=["tasks"])

app/api/endpoints/health.py

@@ -0,0 +1,24 @@
+from fastapi import APIRouter, Depends
+from sqlalchemy.orm import Session
+
+from app.db.database import get_db
+
+router = APIRouter()
+
+
+@router.get("/", response_model=dict)
+def health_check(db: Session = Depends(get_db)):
+    """
+    Health check endpoint to verify API and database connectivity.
+    """
+    try:
+        # Try to execute a simple query to check DB connection
+        db.execute("SELECT 1")
+        db_status = "healthy"
+    except Exception:
+        db_status = "unhealthy"
+
+    return {
+        "status": "ok",
+        "database": db_status,
+    }

app/api/endpoints/tasks.py

@@ -0,0 +1,90 @@
+from typing import List
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.orm import Session
+
+from app.db.database import get_db
+from app.models.task import Task as TaskModel
+from app.schemas.task import TaskCreate, TaskUpdate, Task
+
+router = APIRouter()
+
+
+@router.post("/", response_model=Task, status_code=status.HTTP_201_CREATED)
+def create_task(task: TaskCreate, db: Session = Depends(get_db)):
+    """
+    Create a new task.
+    """
+    db_task = TaskModel(**task.dict())
+    db.add(db_task)
+    db.commit()
+    db.refresh(db_task)
+    return db_task
+
+
+@router.get("/", response_model=List[Task])
+def read_tasks(
+    skip: int = 0,
+    limit: int = 100,
+    completed: bool = None,
+    priority: int = None,
+    db: Session = Depends(get_db),
+):
+    """
+    Retrieve tasks with optional filtering.
+    """
+    query = db.query(TaskModel)
+    
+    # Apply filters if provided
+    if completed is not None:
+        query = query.filter(TaskModel.completed == completed)
+    
+    if priority is not None:
+        query = query.filter(TaskModel.priority == priority)
+    
+    # Apply pagination
+    tasks = query.order_by(TaskModel.created_at.desc()).offset(skip).limit(limit).all()
+    return tasks
+
+
+@router.get("/{task_id}", response_model=Task)
+def read_task(task_id: int, db: Session = Depends(get_db)):
+    """
+    Get a specific task by ID.
+    """
+    task = db.query(TaskModel).filter(TaskModel.id == task_id).first()
+    if task is None:
+        raise HTTPException(status_code=404, detail="Task not found")
+    return task
+
+
+@router.put("/{task_id}", response_model=Task)
+def update_task(task_id: int, task_update: TaskUpdate, db: Session = Depends(get_db)):
+    """
+    Update a task.
+    """
+    db_task = db.query(TaskModel).filter(TaskModel.id == task_id).first()
+    if db_task is None:
+        raise HTTPException(status_code=404, detail="Task not found")
+    
+    # Update task with provided values, skip None values
+    update_data = task_update.dict(exclude_unset=True)
+    for key, value in update_data.items():
+        setattr(db_task, key, value)
+    
+    db.commit()
+    db.refresh(db_task)
+    return db_task
+
+
+@router.delete("/{task_id}", status_code=status.HTTP_204_NO_CONTENT, response_model=None)
+def delete_task(task_id: int, db: Session = Depends(get_db)):
+    """
+    Delete a task.
+    """
+    db_task = db.query(TaskModel).filter(TaskModel.id == task_id).first()
+    if db_task is None:
+        raise HTTPException(status_code=404, detail="Task not found")
+    
+    db.delete(db_task)
+    db.commit()
+    return None

app/db/database.py

@@ -0,0 +1,27 @@
+from pathlib import Path
+
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+
+# Create database directory if it doesn't exist
+DB_DIR = Path("/app") / "storage" / "db"
+DB_DIR.mkdir(parents=True, exist_ok=True)
+
+SQLALCHEMY_DATABASE_URL = f"sqlite:///{DB_DIR}/db.sqlite"
+
+engine = create_engine(
+    SQLALCHEMY_DATABASE_URL,
+    connect_args={"check_same_thread": False}
+)
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+Base = declarative_base()
+
+
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

app/main.py

@@ -0,0 +1,26 @@
+from fastapi import FastAPI
+from fastapi.middleware.cors import CORSMiddleware
+
+from app.api.api import api_router
+from app.db.database import engine, Base
+
+# Create the database tables if they don't exist
+Base.metadata.create_all(bind=engine)
+
+app = FastAPI(
+    title="Task Manager API",
+    description="API for managing tasks",
+    version="0.1.0",
+)
+
+# Configure CORS
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],  # In production, you should restrict this to specific origins
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
+# Include API router
+app.include_router(api_router)

app/models/__init__.py

@@ -0,0 +1 @@
+from app.models.task import Task  # noqa

app/models/task.py

@@ -0,0 +1,16 @@
+from datetime import datetime
+from sqlalchemy import Column, Integer, String, Boolean, DateTime, Text
+from app.db.database import Base
+
+
+class Task(Base):
+    __tablename__ = "tasks"
+
+    id = Column(Integer, primary_key=True, index=True)
+    title = Column(String(255), nullable=False)
+    description = Column(Text, nullable=True)
+    completed = Column(Boolean, default=False)
+    priority = Column(Integer, default=0)  # 0: Low, 1: Medium, 2: High
+    due_date = Column(DateTime, nullable=True)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

app/schemas/__init__.py

@@ -0,0 +1 @@
+from app.schemas.task import TaskBase, TaskCreate, TaskUpdate, TaskInDB, Task  # noqa

app/schemas/task.py

@@ -0,0 +1,36 @@
+from datetime import datetime
+from typing import Optional
+from pydantic import BaseModel, Field
+
+
+class TaskBase(BaseModel):
+    title: str = Field(..., max_length=255, description="Title of the task")
+    description: Optional[str] = Field(None, description="Detailed description of the task")
+    completed: bool = Field(False, description="Whether the task is completed")
+    priority: int = Field(0, ge=0, le=2, description="Priority level (0: Low, 1: Medium, 2: High)")
+    due_date: Optional[datetime] = Field(None, description="Due date of the task")
+
+
+class TaskCreate(TaskBase):
+    pass
+
+
+class TaskUpdate(BaseModel):
+    title: Optional[str] = Field(None, max_length=255, description="Title of the task")
+    description: Optional[str] = Field(None, description="Detailed description of the task")
+    completed: Optional[bool] = Field(None, description="Whether the task is completed")
+    priority: Optional[int] = Field(None, ge=0, le=2, description="Priority level (0: Low, 1: Medium, 2: High)")
+    due_date: Optional[datetime] = Field(None, description="Due date of the task")
+
+
+class TaskInDB(TaskBase):
+    id: int
+    created_at: datetime
+    updated_at: datetime
+
+    class Config:
+        orm_mode = True
+
+
+class Task(TaskInDB):
+    pass

main.py

@@ -0,0 +1,4 @@
+import uvicorn
+
+if __name__ == "__main__":
+    uvicorn.run("app.main:app", host="0.0.0.0", port=8000, reload=True)

migrations/env.py

@@ -0,0 +1,81 @@
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+
+from alembic import context
+from app.db.database import Base
+from app.models import Task  # noqa
+
+# 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
+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:
+        is_sqlite = connection.dialect.name == 'sqlite'
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata,
+            render_as_batch=is_sqlite,  # Add this for SQLite
+            compare_type=True,
+        )
+
+        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/001_create_tasks_table.py

@@ -0,0 +1,37 @@
+"""create tasks table
+
+Revision ID: 001
+Revises: 
+Create Date: 2023-09-25
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '001'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.create_table(
+        'tasks',
+        sa.Column('id', sa.Integer(), nullable=False),
+        sa.Column('title', sa.String(255), nullable=False),
+        sa.Column('description', sa.Text(), nullable=True),
+        sa.Column('completed', sa.Boolean(), default=False),
+        sa.Column('priority', sa.Integer(), default=0),
+        sa.Column('due_date', sa.DateTime(), nullable=True),
+        sa.Column('created_at', sa.DateTime(), default=sa.func.now()),
+        sa.Column('updated_at', sa.DateTime(), default=sa.func.now(), onupdate=sa.func.now()),
+        sa.PrimaryKeyConstraint('id'),
+    )
+    op.create_index(op.f('ix_tasks_id'), 'tasks', ['id'], unique=False)
+
+
+def downgrade():
+    op.drop_index(op.f('ix_tasks_id'), table_name='tasks')
+    op.drop_table('tasks')

requirements.txt

@@ -0,0 +1,7 @@
+fastapi>=0.103.1
+uvicorn>=0.23.2
+sqlalchemy>=2.0.20
+pydantic>=2.3.0
+alembic>=1.12.0
+python-dotenv>=1.0.0
+ruff>=0.0.286