I am using Flask with SQLAlchemy and PostGresDB and getting this error on an insert;
sqlalchemy.exc.ProgrammingError: (psycopg2.ProgrammingError) can't adapt type 'dict'
[SQL: 'SELECT results.id AS results_id,......]
models.py is as follows (just the ORM)
class Result(db.Model):
__tablename__ = 'results'
id = db.Column(db.Integer, primary_key=True)
url = db.Column(db.String())
cities = db.Column(JSON)
states = db.Column(JSON)
app.py for the insert part is;
import os
from flask import Flask, render_template, request, jsonify
from flask_sqlalchemy import SQLAlchemy
app = Flask(__name__)
app.config.from_object(os.environ['APP_SETTINGS'])
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
db = SQLAlchemy(app)
frequency_cities = Counter(city_pop) # dict object
frequency_states = Counter(state_pop) # dict object
try:
from models import Result
result = Result(
url= url,
cities=frequency_cities,
states=frequency_states
)
db.session.add(result)
db.session.commit()
return result.id
except:
errors.append("Unable to add item to database.")
return {"error": errors}
I am at a loss.
Related
I'm trying to learn Flask and use postgresql with it. I'm following this tutorial https://realpython.com/flask-by-example-part-2-postgres-sqlalchemy-and-alembic/, but I keep getting error.
Cannot import name 'AorticStenosis' from partially initialized module 'models' (most likely due to a circular import)
I understand the problem, but I can't figure out how to fix it. So, I started playing around and try to use the steps by step tutorial on something that I'm working on, but I still get the same problem.
Here's my attempt:
Models.py
from app import db
class AorticStenosis(db.Model):
__tablename__ = 'wvu-model'
id = db.Column(db.Integer, primary_key=True)
ip_address = db.Column(db.String())
date_created = db.Column(db.DateTime, default=datetime.utcnow)
e_prime = db.Column(db.Float())
LVMi = db.Column(db.Float())
A = db.Column(db.Float())
LAVi = db.Column(db.Float())
E_e_prime = db.Column(db.Float())
EF = db.Column(db.Float())
E = db.Column(db.Float())
E_A = db.Column(db.Float())
TRV = db.Column(db.Float())
prediction = db.Column(db.String())
def __init__(self, ip_address, e_prime, LVMi, A, E_e_prime, EF, E, E_A, TRV, prediction):
print('initialized')
self.ip_address = ip_address
self.e_prime = e_prime
self.LVMi = LVMi
self.A = A
self.LAVi = LAVi
self.E_e_prime = E_e_prime
self.EF = EF
self.E = E
self.E_A = E_A
self.TRV = TRV
self.prediction = prediction
def __repr__(self):
return '<id {}>'.format(self.id)
app.py
import os
import ast
import bcrypt
from flask import Flask, redirect, render_template, request, session, url_for
import flask_login
from flask_sqlalchemy import SQLAlchemy
from bigml.deepnet import Deepnet
from bigml.api import BigML
import pickle as pkl
import sklearn
app = Flask(__name__)
if app.config['ENV'] == 'production':
app.config.from_object('as_config.ProductionConfig')
else:
app.config.from_object("config.DevelopmentConfig")
# app.config.from_pyfile('as_config.py')
# app.config.from_object(os.environ['APP_SETTINGS'])
# app.config.from_object('as_config.DevelopmentConfig')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
db = SQLAlchemy(app)
from models import AorticStenosis
login_key = app.config['LOGIN_KEY']
api_key = app.config['API_KEY']
model = app.config['MODEL']
api = BigML(login_key, api_key)
deepnet = Deepnet(model, api=api)
scaler = pkl.load(open("scaler.pkl", "rb"))
#app.route("/", methods=["GET", "POST"])
def home():
prediction = None
if request.method == "POST":
form_data = [
float(request.form.get("e_prime")),
float(request.form.get("LVMi")),
float(request.form.get("A")),
float(request.form.get("LAVi")),
float(request.form.get("E_e_prime")),
float(request.form.get("EF")),
float(request.form.get("E")),
float(request.form.get("E_A")),
float(request.form.get("TRV"))
]
form_data = scaler.transform([form_data])[0]
print(form_data)
prediction = str(deepnet.predict({
"e_prime": form_data[0],
"LVMi": form_data[1],
"A": form_data[2],
"LAVi": form_data[3],
"E_e_prime": form_data[4],
"EF": form_data[5],
"E": form_data[6],
"E_A": form_data[7],
"TRV": form_data[8]
}, full=True))
prediction = ast.literal_eval(prediction)
print(prediction)
## get ip address from the user
ip_address = request.environ['REMOTE_ADDR']
print("ip_address: ", ip_address)
try:
aorticStenosis = AorticStenosis(
ip_address = ip_address,
e_prime = form_data[0],
LVMi = form_data[1],
A = form_data[2],
LAVi = form_data[3],
E_e_prime = form_data[4],
EF = form_data[5],
E = form_data[6],
E_A = form_data[7],
TRV = form_data[8]
)
db.session.add(aorticStenosis)
db.session.commit()
except Exception as e:
print(str(e))
if prediction["prediction"] == "1":
prediction["prediction"] = "Low Risk"
prediction["probability"] = round(
1 - prediction["probability"], 6)
elif prediction["prediction"] == "2":
prediction["prediction"] = "High Risk"
else:
prediction["prediction"] = "No prediction was made!"
return render_template("home.html",
prediction=prediction["prediction"],
probability=prediction["probability"])
else:
return render_template("home.html")
if __name__ == "__main__":
app.run(host="0.0.0.0", port="8000")
I made a new file database.py and defined db there.
database.py
from flask_sqlalchemy import SQLAlchemy
db = SQLAlchemy()
def init_app(app):
db.init_app(app)
app.py
import database
...
database.init_app(app)
models.py
from database import db
...
I want to insert JSON type of data in PostgreSQL Database from flask
eg: {"a":[1,2,3] , "b":[1,2,3]}
One example for such data is Phone.no and Childrens, One person can have multiple ph.no and Childrens
In flask View
#app.route('/add', methods=['POST'])
def addRex():
Name = request.form[‘name’]
data = request.get_json(force=False, silent=False, cache=True)
p = Projects(name=name,data = data)
db.session.add(p)
db.session.commit()
In HTTP post method
def addData():
name = input ('Enter Name :')
data = input('Enter Data :')
headers = {'Content-type': 'application/json', 'Accept': 'text/plain'}
r = requests.post(localhost:5000/add,
data ={'name':name}, json={'data':data})
if (r.status_code == 200):print(' Added Successfully!!') else:print('Already exists!')
How can I insert such kind of data from flask into postgresql.
if Anyone can help me with my problem.
Thanks in advance
From sqlalchemy dialect, you can select JSON for Postgres. Here is an example,
from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from sqlalchemy.dialects.postgresql import JSON
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'postgres://username:password#localhost:5432/db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = True
db = SQLAlchemy(app)
class Person(db.Model):
person_name = db.Column(db.Text, primary_key=True)
details = db.Column(JSON)
# db.create_all() ==> for creating the db
per_1 = Person(person_name='Batman', details={"phone_no": [5, 6, 7, 8, 9], "children": {"son": [
"Dick Grayson", "Jason Todd", "Damian Wayne", "Tim Drake"], "daughter": ['Helena Wayne']}})
db.session.add(per_1)
db.session.commit()
I am new to REST API and starting building first REST API app using Flask, SQLAlchemy & Marshmallow. This is my app.py file:
from flask import Flask, request, jsonify
from flask_sqlalchemy import SQLAlchemy
from flask_marshmallow import Marshmallow
import os
# Initialize App
app = Flask(__name__)
basedir = os.path.abspath(os.path.dirname(__file__))
# Database Setup
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///' + os.path.join(basedir, 'db.sqlite')
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
# Init db
db = SQLAlchemy(app)
# Init marshmallow
ma = Marshmallow(app)
# Product Class/Model
class Product(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.String(100), unique=True)
description = db.Column(db.String(200))
price = db.Column(db.Float)
qty = db.Column(db.Integer)
def __init__(self, name, description, price, qty):
self.name = name
self.description = description
self.price = price
self.qty = qty
# Product Schema
class ProductSchema(ma.Schema):
class Meta:
fields = ('id', 'name', 'description', 'price', 'qty')
# Init Schema
product_schema = ProductSchema()
products_schema = ProductSchema(many=True)
# Create Product
#app.route('/product', methods=['POST'])
def add_product():
name = request.json['name']
description = request.json['description']
price = request.json['price']
qty = request.json['qty']
new_product = Product(name, description, price, qty)
db.session.add(new_product)
db.session.commit()
return product_schema.jsonify(new_product)
# Get All Products
#app.route('/receive', methods=['GET'])
def get_products():
all_products = Product.query.all()
result = products_schema.dump(all_products)
return jsonify(result)
# Run the Server
if __name__ == '__main__':
app.run(debug=True)
For generating SQLite database, I have to open python interactive shell and then there I have to do this:
from app import db
db.create_all()
But I have to genreate database from app.py itself so I am inserting the same commands inside app.py, but it's giving me error:
OperationalError: (sqlite3.OperationalError) no such table: product
How do I generate a database from app.py?
Where are you placing your db.create_all()? The error may simply be a result of placement. When I copy and paste your code into PyCharm (running Python 3.7) it creates the DB fine when I place
db.create_all()
immediately before
# Run the Server
if __name__ == '__main__':
app.run(debug=True)
If you try to run db.create_all() before you instantiate the db object it will throw an error because db does not exist yet.
You should not need to use "from app import db" at all because the db object is declared up top.
please; can someone tell me what's wrong with this code?, i tried to connect to my postgre sql database with flask sqlalchemy but i keep having an error that db is not defined. NB: all modules are installed and loaded successfully.
app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'postgresql://postgres:....'
db = SQLAlchemy(app)
class Person(db.Model):
id = db.Column(db.Integer, primary_key=True)
name = db.Column(db.Text)
age = db.Column(db.Integer)
def __init__(self, name, age):
self.name = name
self.age = age
def __repr__(self):
return "Name:{}\tAge:{}".format(self.name, self.age)
def create_database():
db.create_all()
print('Database created....')
if __name__ == "__main__":
create_database()
First do a pip for sqlalchemy_utils i.e. pip install sqlalchemy_utils
and then,
You need to use engine for creating the DB:
from sqlalchemy import create_engine
from sqlalchemy_utils import database_exists, create_database
engine = create_engine("postgres://localhost/somedb")
if not database_exists(engine.url):
create_database(engine.url)
print(database_exists(engine.url))
So I'm trying to learn Flask and MongoDB using MongoAlchemy and I'm running into an issue when trying to query my app for data, I'm not sure what I'm doing wrong. I've searched through the MongoAlchemy documentation and followed a few StackOverflow posts to no real avail. Here's my code:
from flask import Flask, jsonify, request
from flask_mongoalchemy import MongoAlchemy
app = Flask(__name__)
app.config['MONGOALCHEMY_DATABASE'] = 'user'
app.config['MONGOALCHEMY_SERVER_AUTH'] = False
db = MongoAlchemy(app)
class User(db.Document):
user_name = db.StringField()
password = db.StringField()
first_name = db.StringField()
last_name = db.StringField()
phone_number = db.StringField()
def init_app():
app = Flask(__name__)
db.init_app(app)
return app
user_1 = User(user_name = "user1",
password = "password",
first_name = "John",
last_name = "Doe",
phone_number = "123-456-7890")
user_1.save()
#app.route('/', methods=['GET', 'POST'])
def index():
return "Hello, world!"
#app.route('/user/<user_name>', methods=['GET', 'POST'])
def findUser(user_name=None):
uName = request.args.get('user_name', user_name)
user = User.query.filter({User.user_name:uName}).first()
return jsonify(user)
##=====================================================================
if __name__ == '__main__':
app.run(debug=True)
When I go to localhost:5000/user/user1 it returns null, I'm not sure what I'm doing wrong? Thanks in advance!
Referenced Posts:
MongoAlchemy query embedded documents
Flask Value error view function did not return a response
http://www.mongoalchemy.org/api/schema/document.html