app.py

from flask import Flask,request,jsonify,make_response
from flask_sqlalchemy import SQLAlchemy
from os import environ

app=Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI']=environ.get("DB_URL")
db=SQLAlchemy(app)

class User(db.Model):
    __tablename__='user'

    id=db.Column(db.Integer,primary_key=True)
    username=db.Column(db.String(80),unique=True,nullable=False)
    email=db.column(db.string(120),unique=True,nullable=False)

    def __init__(self,username,email):
        self.username=username
        self.email=email

    def json(self):
        return{'id':id,'username':self.username,'email':self.email}
    
db.create_all()

#create a text route

@app.route('/test',methods=['GET'])
def test():
    return make_response(jsonify({'message':'test_route'}),200)


@app.route('/users',methods=['POST'])
def create_user():
    try:
        data=request.get_json()
        new_user=User(username=data['username'],email=data['email'])
        db.session.add(new_user)
        db.session.commit()
        return make_response(jsonify({'message':'User created'}),201)
    except Exception as e:
        return make_response(jsonify({'message':'error User creating'}),500)
# get all users
@app.route('/users', methods=['GET'])
def get_users():
  try:
    users = User.query.all()
    return make_response(jsonify([user.json() for user in users]), 200)
  except Exception as e:
    return make_response(jsonify({'message': 'error getting users'}), 500)
  
  # get a user by id
@app.route('/users/<int:id>', methods=['GET'])
def get_user(id):
  try:
    user = User.query.filter_by(id=id).first()
    if user:
      return make_response(jsonify({'user': user.json()}), 200)
    return make_response(jsonify({'message': 'user not found'}), 404)
  except Exception as e:
    return make_response(jsonify({'message': 'error getting user'}), 500)

    
# update a user
@app.route('/users/<int:id>', methods=['PUT'])
def update_user(id):
  try:
    user = User.query.filter_by(id=id).first()
    if user:
      data = request.get_json()
      user.username = data['username']
      user.email = data['email']
      db.session.commit()
      return make_response(jsonify({'message': 'user updated'}), 200)
    return make_response(jsonify({'message': 'user not found'}), 404)
  except Exception as e:
    return make_response(jsonify({'message': 'error updating user'}), 500)
  
  # delete a user
@app.route('/users/<int:id>', methods=['DELETE'])
def delete_user(id):
  try:
    user = User.query.filter_by(id=id).first()
    if user:
      db.session.delete(user)
      db.session.commit()
      return make_response(jsonify({'message': 'user deleted'}), 200)
    return make_response(jsonify({'message': 'user not found'}), 404)
  except Exception as e:
    return make_response(jsonify({'message': 'error deleting user'}), 500)