frontend

blueprint

frontend/ src/ components/ PersonForm.jsx PersonList.jsx pages/ Home.jsx services/ api.js # axios config App.jsx package.json

backend start order

Great question 👍 — order matters a lot when you’re starting a FastAPI + SQLAlchemy + Postgres project. Here’s the recommended sequence from zero (like enterprises do):

---

🔹 Step 1: Setup project structure

• Create the folder layout (backend/app/...).

• Add empty __init__.py files so imports work.

• Add requirements.txt with dependencies.

• if u made changes in version then run pip install -r requirements.txt --upgrade --force-reinstall

---

🔹 Step 2: Database layer

1. database.py → setup SQLAlchemy engine, SessionLocal, and Base.

2. models.py → define your DB tables (ORM models).

3. alembic init → initialize Alembic for migrations.

---

🔹 Step 3: Schemas

• schemas.py → create Pydantic models for request/response (PersonCreate, PersonOut).

• These map closely to models.py, but keep API clean and validated.

---

🔹 Step 4: Business logic

• crud.py → write functions to insert/query/update data using SQLAlchemy.

• Keep DB queries out of routes for clean separation.

---

🔹 Step 5: API layer

1. routers/persons.py → build API routes (POST /persons, GET /persons, etc.).

2. app/main.py → create FastAPI app instance, include routers, add root health-check route.

---

🔹 Step 6: Migrations

• Run Alembic to generate migrations from models.py.

• Apply migrations to create/update your PostgreSQL schema.

---

🔹 Step 7: Testing

• Run backend with:

  uvicorn app.main:app --reload

• Check API docs at http://127.0.0.1:8000/docs.

---

✅ Final Sequence (file order to work on):

1. requirements.txt

2. database.py

3. models.py

4. alembic/ (init + first migration)

5. schemas.py

6. crud.py

7. routers/persons.py

8. main.py

---

Would you like me to start coding these step by step for you (beginning with database.py), so you can just copy-paste and run?

frontend and backend code

Excellent 🚀 your database is ready — now let’s build the backend + frontend in a clean way so it scales like an enterprise project.

---

🔑 Where enterprises start?

Most teams start from the backend first:

• Define API contract (schemas, endpoints, validation).

• Expose mock or real endpoints.

• Then frontend consumes them.

This ensures the database + API are solid before UI connects. Some companies do “API-first design” → publish OpenAPI/Swagger docs so frontend devs can start in parallel.

So let’s start with the backend (Python + FastAPI + Postgres), then do the frontend (React).

---

🐍 Backend Setup (FastAPI + SQLAlchemy + Alembic)

1. Folder structure

backend/
  app/
    __init__.py  // Purpose: Turns a directory into a Python package.
    main.py      // Entry point of your FastAPI app. includes routes and runs the app
    database.py  // Handles database connection setup (SQLAlchemy engine, session, base).
    models.py    // Contains SQLAlchemy ORM models (database tables).
    schemas.py   // Defines Pydantic models for request/response validation.
    crud.py      // Business logic layer. Handles DB queries separate from API routes.
    routers/     // Holds modular route files (keeps API endpoints organized).
      __init__.py
      persons.py
  alembic/            # migrations
  alembic.ini
  requirements.txt  // Lists Python dependencies.

---

2. requirements.txt

fastapi   // Web framework to build REST APIs quickly with async support.
uvicorn[standard]  // ASGI server to run FastAPI apps in production.
sqlalchemy // ORM & SQL toolkit for defining models and querying PostgreSQL.
psycopg2-binary   // PostgreSQL database driver used by SQLAlchemy to connect.
alembic  // Migration tool to version-control database schema changes.
pydantic  // Data validation & serialization library (used in FastAPI schemas).
python-dotenv  // Loads environment variables from a .env file for configs.

---

3. database.py

from sqlalchemy import create_engine
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker
import os

DB_USER = os.getenv("DB_USER", "daybuddy_user")
DB_PASS = os.getenv("DB_PASS", "change_me_strong_password")
DB_HOST = os.getenv("DB_HOST", "localhost")
DB_PORT = os.getenv("DB_PORT", "5432")
DB_NAME = os.getenv("DB_NAME", "daybuddy")

SQLALCHEMY_DATABASE_URL = f"postgresql://{DB_USER}:{DB_PASS}@{DB_HOST}:{DB_PORT}/{DB_NAME}"

engine = create_engine(SQLALCHEMY_DATABASE_URL)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

Base = declarative_base()

---

4. models.py

from sqlalchemy import Column, Integer, String, Text, TIMESTAMP, func
from .database import Base

class Person(Base):
    __tablename__ = "persons"

    id = Column(Integer, primary_key=True, index=True)
    name = Column(String, nullable=False)
    email = Column(String, nullable=True)
    company = Column(String, nullable=True)
    mobile = Column(String, nullable=True)
    details = Column(Text, nullable=True)
    company_size = Column(Integer, nullable=True)
    url = Column(String, nullable=True)
    location = Column(String, nullable=True)
    created_at = Column(TIMESTAMP(timezone=True), server_default=func.now())

---

5. schemas.py

from pydantic import BaseModel, EmailStr, HttpUrl
from typing import Optional
from datetime import datetime

class PersonBase(BaseModel):
    name: str
    email: Optional[EmailStr] = None
    company: Optional[str] = None
    mobile: Optional[str] = None
    details: Optional[str] = None
    company_size: Optional[int] = None
    url: Optional[HttpUrl] = None
    location: Optional[str] = None

class PersonCreate(PersonBase):
    name: str

class PersonRead(PersonBase):
    id: int
    created_at: datetime

    class Config:
        orm_mode = True

---

6. crud.py

from sqlalchemy.orm import Session
from . import models, schemas

def get_persons(db: Session, skip: int = 0, limit: int = 100):
    return db.query(models.Person).offset(skip).limit(limit).all()

def create_person(db: Session, person: schemas.PersonCreate):
    db_person = models.Person(**person.dict())
    db.add(db_person)
    db.commit()
    db.refresh(db_person)
    return db_person

---

7. routers/persons.py

from fastapi import APIRouter, Depends
from sqlalchemy.orm import Session
from .. import schemas, crud, database
from typing import List

router = APIRouter(prefix="/persons", tags=["persons"])

def get_db():
    db = database.SessionLocal()
    try:
        yield db
    finally:
        db.close()

@router.get("/", response_model=List[schemas.PersonRead])
def list_persons(skip: int = 0, limit: int = 100, db: Session = Depends(get_db)):
    return crud.get_persons(db, skip=skip, limit=limit)

@router.post("/", response_model=schemas.PersonRead)
def create_person(person: schemas.PersonCreate, db: Session = Depends(get_db)):
    return crud.create_person(db=db, person=person)

---

8. main.py

from fastapi import FastAPI
from .routers import persons
from .database import Base, engine

# Create tables (for dev; in prod use Alembic migrations)
Base.metadata.create_all(bind=engine)

app = FastAPI(title="Person API")

app.include_router(persons.router)

---

9. Run backend

uvicorn app.main:app --reload --port 8000

• Docs auto-generated at: http://localhost:8000/docs

---

⚛️ Frontend Setup (React + Axios + Tailwind)

1. Create project

npm create vite@latest frontend --template react
cd frontend
npm install axios
npm install -D tailwindcss postcss autoprefixer
npx tailwindcss init -p

In tailwind.config.js:

content: ["./index.html", "./src/**/*.{js,jsx,ts,tsx}"]

In src/index.css add:

@tailwind base;
@tailwind components;
@tailwind utilities;

---

2. src/services/api.js

import axios from "axios";

const api = axios.create({
  baseURL: "http://localhost:8000",
});

export default api;

---

3. src/components/PersonForm.jsx

import { useState } from "react";
import api from "../services/api";

export default function PersonForm({ onAdded }) {
  const [form, setForm] = useState({ name: "", email: "", company: "", mobile: "", details: "", company_size: "", url: "", location: "" });

  const handleChange = (e) => {
    setForm({ ...form, [e.target.name]: e.target.value });
  };

  const handleSubmit = async (e) => {
    e.preventDefault();
    if (!form.name) return alert("Name is required!");
    try {
      const res = await api.post("/persons/", form);
      onAdded(res.data);
      setForm({ name: "", email: "", company: "", mobile: "", details: "", company_size: "", url: "", location: "" });
    } catch (err) {
      console.error(err);
      alert("Error saving person");
    }
  };

  return (
    <form onSubmit={handleSubmit} className="space-y-2">
      <input className="border p-2 w-full" name="name" placeholder="Name *" value={form.name} onChange={handleChange} required />
      <input className="border p-2 w-full" name="email" placeholder="Email" value={form.email} onChange={handleChange} />
      <input className="border p-2 w-full" name="company" placeholder="Company" value={form.company} onChange={handleChange} />
      <input className="border p-2 w-full" name="mobile" placeholder="Mobile" value={form.mobile} onChange={handleChange} />
      <input className="border p-2 w-full" name="details" placeholder="Details" value={form.details} onChange={handleChange} />
      <input className="border p-2 w-full" type="number" name="company_size" placeholder="Company Size" value={form.company_size} onChange={handleChange} />
      <input className="border p-2 w-full" name="url" placeholder="URL" value={form.url} onChange={handleChange} />
      <input className="border p-2 w-full" name="location" placeholder="Location" value={form.location} onChange={handleChange} />
      <button className="bg-blue-600 text-white p-2 rounded">Save</button>
    </form>
  );
}

---

4. src/components/PersonList.jsx

export default function PersonList({ persons }) {
  return (
    <ul className="mt-4 space-y-2">
      {persons.map((p) => (
        <li key={p.id} className="border rounded p-2">
          <div className="font-bold">{p.name}</div>
          {p.email && <div>{p.email}</div>}
          {p.company && <div>{p.company}</div>}
          <div className="text-sm text-gray-500">Added {new Date(p.created_at).toLocaleString()}</div>
        </li>
      ))}
    </ul>
  );
}

---

5. src/pages/Home.jsx

import { useEffect, useState } from "react";
import api from "../services/api";
import PersonForm from "../components/PersonForm";
import PersonList from "../components/PersonList";

export default function Home() {
  const [persons, setPersons] = useState([]);

  useEffect(() => {
    api.get("/persons/").then((res) => setPersons(res.data));
  }, []);

  const handleAdded = (newPerson) => {
    setPersons([newPerson, ...persons]);
  };

  return (
    <div className="p-4 max-w-xl mx-auto">
      <h1 className="text-2xl font-bold mb-4">Person Registry</h1>
      <PersonForm onAdded={handleAdded} />
      <PersonList persons={persons} />
    </div>
  );
}

---

6. src/App.jsx

import Home from "./pages/Home";

function App() {
  return <Home />;
}

export default App;

---

✅ Next steps

• Run backend with uvicorn.

• Run frontend with npm run dev.

• Try adding a person → check DB → verify list updates.

• Later, add Dockerfiles for frontend & backend.

• Then wrap with Helm/Kubernetes.

---

Do you want me to add Alembic migrations setup now (so schema changes are tracked properly, like enterprises do), or keep it simple with Base.metadata.create_all for now?