Claims not declared, but is... why?

[Ecniv]

Hi

My class which I've imported in the app.py is complaining that the con variable doesn`t exist.

Ok. I get that it thinks the variable doesn`t exist, but it does. before the route is called, it is set up.

When you import, does it evaluate the class at that time (if so then that is why.. the variable is only created after the import)

from flask import Flask, render_template, flash, redirect, url_for, session, request
from flask import send_from_directory, logging

import os
import pymysql
import random

from setup import setupADB

app = Flask(__name__)
app.debug = True
app.config.from_object(__name__)
app.config['SECRET_KEY'] = 'development key'

con = pymysql.connect(
    host="localhost",
    user="root",
    password="thepwd",
    db="pyadventures",
    charset="utf8mb4",
    cursorclass=pymysql.cursors.DictCursor
    )


#the routes
@app.route('/favicon.ico')
def rFavicon():
    return redirect(url_for('static', filename='favicon.ico'), code=302)

@app.route('/')
def rIndex():
    return render_template("home.html")

@app.route('/setup1time')
def rSetupOneTime():
    r = []
    d = setupADB()
    d.createdb()
    r = d.dbtables()
    return 'l'
    #return render_template('setup.html',r=r)

if __name__ == '__main__':
	app.run()

and the class

class setupADB:
#    def __init__(self):
        #meh

    def createdb(self):
        '''
        on the command line...
        mysql -u root -p
        grant all priveledges on *.* to 'thtename'@'localhost' identifiedby 'pwd';
        \q
        mysql -u username -p
        create database nameofdatabase
        use nameofdatabase
        (or use the mysql manager, create a new schema (database) )
        '''

    def dbtables(self):
        r = []
        sql = ''
#complains on the following line - con should be global from the app.py???
        with con.cursor() as cr:
            try:
                sql = """CREATE TABLE ... sql
                """
                cr.execute(sql)
            except Exception as e:
                r.append("_su -> "+str(e))
            try:
                sql = """CREATE TABLE ... sql
                """
                cr.execute(sql)
            except Exception as e:
                r.append("stories -> "+str(e))
        return r

[Larz60+]

Please show the actual error, complete and unaltered.
There is so much information packed in there, and we need it all.

[Ecniv]

Error:
builtins.NameError

NameError: name 'con' is not defined
Traceback (most recent call last)

    File "c:\python\lib\site-packages\flask\app.py", line 2309, in __call__

    return self.wsgi_app(environ, start_response)

    File "c:\python\lib\site-packages\flask\app.py", line 2295, in wsgi_app

    response = self.handle_exception(e)

    File "c:\python\lib\site-packages\flask\app.py", line 1741, in handle_exception

    reraise(exc_type, exc_value, tb)

    File "c:\python\lib\site-packages\flask\_compat.py", line 35, in reraise

    raise value

    File "c:\python\lib\site-packages\flask\app.py", line 2292, in wsgi_app

    response = self.full_dispatch_request()

    File "c:\python\lib\site-packages\flask\app.py", line 1815, in full_dispatch_request

    rv = self.handle_user_exception(e)

    File "c:\python\lib\site-packages\flask\app.py", line 1718, in handle_user_exception

    reraise(exc_type, exc_value, tb)

    File "c:\python\lib\site-packages\flask\_compat.py", line 35, in reraise

    raise value

    File "c:\python\lib\site-packages\flask\app.py", line 1813, in full_dispatch_request

    rv = self.dispatch_request()

    File "c:\python\lib\site-packages\flask\app.py", line 1799, in dispatch_request

    return self.view_functions[rule.endpoint](**req.view_args)

    File "D:\Dev\python\py3\webAdventureDB\app.py", line 39, in rSetupOneTime

    r = d.dbtables()

    File "D:\Dev\python\py3\webAdventureDB\setup.py", line 20, in dbtables

    with con.cursor() as cr:

    NameError: name 'con' is not defined

[Larz60+]

in second module:

class setupADB:
    def __init__(self, con):
        self.con = con

then refer to con in rest of class as self.con

also, line 37 of first script

    d = setupADB(con)

[Ecniv]

Ah thank you... Thought it would be easy.
Can I use the global in the def or would that be bad practice?

[Larz60+]

should never use global unless there is no other way.
I haven't used a global as far back as I can remember.