feat: add database connection with modified endpoints

.env.example

@@ -0,0 +1,4 @@
+DATABASE_URL=postgresql://user:password@localhost:5432/mydatabase
+
+# [dev, stage, prod]
+ENVIRONMENT=dev

.gitignore

@@ -131,7 +131,11 @@ dmypy.json
 .profiling/
 
 # vscode settings
-.vscode/
+.vscode/*
+!.vscode/extensions.json
+!.vscode/rest-client.env.json
+!.vscode/http
+!.vscode/sql
 
 # FastAPI specifics
 # .env files used for storing environment variables should not be committed to version control

.vscode/extensions.json

@@ -0,0 +1,12 @@
+{
+    "recommendations": [
+        "ms-python.python",
+        "ms-python.debugpy",
+        "mtxr.sqltools",
+        "mtxr.sqltools-driver-pg",
+        "genieai.chatgpt-vscode",
+        "humao.rest-client"
+    ],
+    "unwantedRecommendations": [
+    ]
+}

.vscode/http/url.rest

@@ -0,0 +1,10 @@
+### redirect_to_original_url
+GET http://localhost:8000/
+
+### create_url_shortcode
+POST http://localhost:8000/shorten
+Content-Type: application/json
+
+{
+    "url": "https://google.com/"
+}

.vscode/sql/minxadb-dev.session.sql

@@ -0,0 +1 @@
+SELECT * FROM url_mapping

dependencies/database.py

@@ -0,0 +1,16 @@
+import os
+from databases import Database
+from sqlalchemy import create_engine, MetaData
+from sqlalchemy.orm import declarative_base, sessionmaker
+
+DATABASE_URL = os.getenv("DATABASE_URL")
+
+# for Alembic migrations and sync operations
+engine = create_engine(DATABASE_URL)
+
+# to use with async requests
+database = Database(DATABASE_URL)
+
+metadata = MetaData()
+Base = declarative_base(metadata=metadata)
+

dependencies/models.py

@@ -0,0 +1,9 @@
+from sqlalchemy import Column, Integer, String
+from dependencies.database import Base
+
+class UrlMapping(Base):
+    __tablename__ = "url_mapping"
+
+    id = Column(Integer, primary_key=True, index=True)
+    url = Column(String, nullable=False)
+    shortcode = Column(String, index=True, unique=True, nullable=False)

main.py

@@ -1,27 +1,57 @@
-from fastapi import FastAPI
+import os
-from .models import UrlPayload
+
-from .utils import generate_shortcode
+from sqlalchemy.exc import IntegrityError
+from fastapi import FastAPI, HTTPException
+from fastapi.responses import RedirectResponse
+
+from dependencies.models import UrlMapping
+from dependencies.database import database, Base, engine
+from schemas import UrlPayload
+from utils import generate_shortcode
 
 app = FastAPI()
 
-# temporary data store
+@app.on_event("startup")
-url_mapping = {}
+async def startup():
+    await database.connect()
+    Base.metadata.create_all(bind=engine) # TODO: create all tables if not present (ONLY DEVELOPMENT)
+
+@app.on_event("shutdown")
+async def shutdown():
+    await database.disconnect()
+
+
 
 @app.get("/{shortcode}")
-async def get_original_url(shortcode: str):
+async def redirect_to_original_url(shortcode: str):
-    if shortcode in url_mapping:
+    # TODO: do validation check for valid shortcode
-        return {"original_url": url_mapping[shortcode]}
+    if not shortcode:
+        raise HTTPException(status_code=400, detail="Shortcode is not valid")
+
+    query = UrlMapping.__table__.select().where(UrlMapping.shortcode == shortcode)
+    url_mapping = await database.fetch_one(query)
+
+    if url_mapping:
+        return RedirectResponse(url=url_mapping.url, status_code=302)
     else:
         raise HTTPException(status_code=404, detail="Shortcode not found")
 
-
+@app.post("/shorten")
-@app.post("/shorten/")
+async def create_url_shortcode(url_payload: UrlPayload):
-async def create_short_url(url_payload: UrlPayload):
+    original_url = str(url_payload.url) # convert to string from HttpUrl
-    original_url = url_payload.url
     shortcode = generate_shortcode()
 
-    if shortcode in url_mapping:
+    try:
-        raise HTTPException(status_code=409, detail="Shortcode already in use")
+        query = UrlMapping.__table__.insert().values({
+            "url": original_url,
+            "shortcode": shortcode
+        })
+        await database.execute(query)
 
-    url_mapping[shortcode] = str(original_url)
         return {"shortcode": shortcode, "original_url": original_url}
+    except IntegrityError as e:
+        if 'shortcode' in str(e):
+            raise HTTPException(status_code=409, detail="Shortcode already in use")
+        else:
+            raise HTTPException(status_code=500, detail="Internal Server Error")
+    

requirements.txt

@@ -1,12 +1,20 @@
+alembic==1.16.4
 annotated-types==0.7.0
 anyio==4.9.0
+asyncpg==0.30.0
 click==8.2.1
+databases==0.9.0
 fastapi==0.116.1
+greenlet==3.2.3
 h11==0.16.0
 idna==3.10
+Mako==1.3.10
+MarkupSafe==3.0.2
+psycopg2-binary==2.9.10
 pydantic==2.11.7
 pydantic_core==2.33.2
 sniffio==1.3.1
+SQLAlchemy==2.0.41
 starlette==0.47.2
 typing-inspection==0.4.1
 typing_extensions==4.14.1