Reading data from postgres

Author: harishkannarao

Makefile

@@ -36,5 +36,17 @@ flake8:
 run_all:
 	make init ruff flake8 tests_unit tests_integration
 
+docker_compose_pull:
+	docker compose -f docker-compose.yml pull
+
+docker_compose_start:
+	docker compose -f docker-compose.yml up --build -d
+
+docker_compose_stop:
+	docker compose -f docker-compose.yml down -v
+
+docker_compose_restart:
+	make docker_compose_stop docker_compose_start
+
 docker:
 	docker build --pull -t python-fastapi -f Dockerfile .

README.md

@@ -46,13 +46,17 @@ Docker dependencies needs to be started using docker compose before running the
 
     make fast_dev
 
-    http://localhost:8000
+    http://localhost:8000/docs
+
+    http://localhost:8000/context/docs
 
 ### Run in production mode
 
     make fast_run
 
-    http://localhost:8000
+    http://localhost:80000/docs
+
+    http://localhost:8000/context/docs
 
 ### Running with docker
 

app/config.py

@@ -13,6 +13,8 @@ class Settings(BaseSettings):
     app_db_database: str = "myuser"
     app_db_user: str = "myuser"
     app_db_password: str = "superpassword"
+    app_db_min_con: int = 5
+    app_db_max_con: int = 20
     # db settings end
 
 

app/db/__init__.py

@@ -0,0 +1,7 @@
+from databases import Database
+from app.config import settings
+
+DATABASE_URL = f"postgresql://{settings.app_db_user}:{settings.app_db_password}@{settings.app_db_host}/{settings.app_db_database}"
+database = Database(
+    DATABASE_URL, min_size=settings.app_db_min_con, max_size=settings.app_db_max_con
+)

app/db/database_config.py

@@ -5,25 +5,30 @@
 from contextlib import asynccontextmanager
 
 from app.config import settings
+from app.db.database_config import database
 from app.db_schema_migrations.yoyo_migration import apply_db_migrations
 from app.logging.logging_config import setup_logging
 from app.middleware.process_time import ProcessTimeMiddleware
 from app.middleware.request_id import RequestIdMiddleware
 from app.routers.sample import router as sample_router
+from app.routers.customer import router as customer_router
 
 # Initialize logging at application startup
 setup_logging(json_logs=settings.app_json_logs)
 
 context = FastAPI(openapi_url=settings.app_open_api_url)
 
 context.include_router(sample_router)
+context.include_router(customer_router)
 
 
 @asynccontextmanager
 async def lifespan(_app: FastAPI):
     if settings.app_db_migration_enabled:
         apply_db_migrations()
+    await database.connect()
     yield
+    await database.disconnect()
 
 
 app = FastAPI(openapi_url=settings.app_open_api_url, lifespan=lifespan)

app/main.py

@@ -0,0 +1,7 @@
+import dataclasses
+
+
+@dataclasses.dataclass(frozen=True)
+class Customer:
+    first_name: str
+    last_name: str

app/model/__init__.py

@@ -0,0 +1,17 @@
+from fastapi import APIRouter
+
+from app.db.database_config import database
+from app.model.customer import Customer
+
+router = APIRouter()
+
+
+def to_customer(row) -> Customer:
+    return Customer(first_name=row.first_name, last_name=row.last_name)
+
+
+@router.get("/customers/", tags=["users"])
+async def read_customers() -> list[Customer]:
+    rows = await database.fetch_all(query="select * from customers")
+    customers: list[Customer] = list(map(lambda row: to_customer(row), rows))
+    return customers

app/model/customer.py

@@ -9,6 +9,7 @@ dependencies = [
     "psycopg2-binary",
     "yoyo-migrations",
     "testcontainers[postgresql]",
+    "databases[asyncpg]",
 ]
 
 [dependency-groups]