Writing POST method values to MySQL : Forums : PythonAnywhere

Hi Everyone, my use case is this: i want to receive a webhook from Tradingview (JSON formatted) and store it in the database. (Later I'll act on trading, but I will want to record actions to a database so this is my first step. I followed the tutorial that utilizes Flask with MySQL and had no problems writing the comments to the table and displaying them. To that code, I added the POST method. It seems to be handled, but nothing is getting stored.

My send_post.py

import requests
response = requests.post(
    "http://pegasus163.pythonanywhere.com/food",
    json=dict(
        title="A title",
        description="A description"
    )
)
assert response.status_code == 200, "success"

I run it in the window and I get this response:

Traceback (most recent call last):
  File "/home/pegasus163/mysite/send_post.py", line 9, in <module>
    assert response.status_code == 200, "success"
AssertionError: success
>>>

The Access log shows:

3.93.173.252 - - [02/Jul/2022:10:16:41 +0000] "POST /food HTTP/1.1" 500 1184 "-" "python-requests/2.25.1" "3.93.173.252" response-time=0.012

The error logs show:

2022-07-02 10:16:41,003: Error running WSGI application
2022-07-02 10:16:41,009: sqlalchemy.orm.exc.UnmappedInstanceError: Class 'builtins.str' is not mapped
2022-07-02 10:16:41,009:   File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 2069, in __call__
2022-07-02 10:16:41,009:     return self.wsgi_app(environ, start_response)
2022-07-02 10:16:41,009: 
2022-07-02 10:16:41,009:   File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 2054, in wsgi_app
2022-07-02 10:16:41,009:     response = self.handle_exception(e)
2022-07-02 10:16:41,009: 
2022-07-02 10:16:41,009:   File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 2051, in wsgi_app
2022-07-02 10:16:41,009:     response = self.full_dispatch_request()
2022-07-02 10:16:41,010: 
2022-07-02 10:16:41,010:   File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 1501, in full_dispatch_request
2022-07-02 10:16:41,010:     rv = self.handle_user_exception(e)
2022-07-02 10:16:41,010: 
2022-07-02 10:16:41,010:   File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 1499, in full_dispatch_request
2022-07-02 10:16:41,010:     rv = self.dispatch_request()
2022-07-02 10:16:41,010: 
2022-07-02 10:16:41,010:   File "/usr/local/lib/python3.7/site-packages/flask/app.py", line 1485, in dispatch_request
2022-07-02 10:16:41,010:     return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
2022-07-02 10:16:41,010: 
2022-07-02 10:16:41,010:   File "/home/pegasus163/mysite/flask_app.py", line 39, in foo_page
2022-07-02 10:16:41,010:     db.session.add(message)
2022-07-02 10:16:41,011: 
2022-07-02 10:16:41,011:   File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/scoping.py", line 163, in do
2022-07-02 10:16:41,011:     return getattr(self.registry(), name)(*args, **kwargs)
2022-07-02 10:16:41,011: 
2022-07-02 10:16:41,011:   File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/session.py", line 2020, in add
2022-07-02 10:16:41,011:     replace_context=err,
2022-07-02 10:16:41,011: 
2022-07-02 10:16:41,011:   File "/usr/local/lib/python3.7/site-packages/sqlalchemy/util/compat.py", line 182, in raise_
2022-07-02 10:16:41,011:     raise exception

flask_app.py

import requests
from flask import Flask, redirect, render_template, request, url_for, Response
from flask_sqlalchemy import SQLAlchemy
import dbaccess as config

app = Flask(__name__)
app.config["DEBUG"] = True


SQLALCHEMY_DATABASE_URI = "mysql+mysqlconnector://{username}:{password}@{hostname}/{databasename}".format(
    username=config.username,
    password=config.password,
    hostname=config.hostname,
    databasename=config.databasename,
)
app.config["SQLALCHEMY_DATABASE_URI"] = SQLALCHEMY_DATABASE_URI
app.config["SQLALCHEMY_POOL_RECYCLE"] = 299
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False
db = SQLAlchemy(app)

class Comment(db.Model):

    __tablename__ = "comments"

    id = db.Column(db.Integer, primary_key=True)
    content = db.Column(db.String(4096))

@app.route("/", methods=["GET", "POST"])   # from tutorial, works fine
def index():
    if request.method == "GET":
        return render_template("main_page.html", comments=Comment.query.all())
        comment = Comment(content=request.form["contents"])
        db.session.add(comment)
        db.session.commit()

@app.route('/food', methods=["POST"]) # just write message to db to confirm
def foo_page():
    message = "test food"
    db.session.add(message)
    db.session.commit()
    return Response(status=200)

@app.route('/foo', methods=["POST"])  # handle the POST request, write description to db
def form_example():
    if request.method == 'POST':
        request_data = request.get_json()
        if request_data:
            if 'title' in request_data:
                title = request_data['title']
            if 'description' in request_data:
                description = request_data['description']
        db.session.add(description)
        db.session.commit()
    return redirect(url_for('index'))

@app.route('/webhook', methods=['POST'])
def webhook():
    if request.method == 'POST':
        comment = Comment(content=request.form["contents"])
        db.session.add(comment)
        db.session.commit()
        return Response(status=200)
    else:
        abort(400)

    return redirect(url_for('index'))

Note that the send_post is POSTing to /food. I just expect it to make an entry to the database.

Thanks for reading this far. Please advise if you can.

deleted-user-13107958 | 20 posts | July 2, 2022, 10:22 a.m. | permalink