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With existing "mySQL Database" and "website", want to connect/synchronize both part how to accomplish by Python

Main problem: I have existing mySQL Database and website, how do I connect/synchronize both, that input or update from mySQL, can also result in website too
I did learn HTML, CSS but was required to find the way, instead input from <p> </p>, need to find a way CRUD from mySQL, and result to website
after a day of research, python django seems has the possiblity solve my problem, but all the tutorial is buttom up create an new website and new mySQL, I'm stock on connecting existing one (that the "mySQL Database" and "website"), that how far I reach , therefore want to ask the export in here, thanks
environment: I'm using python, window and mySQL
the already set website screenshot
the existing mySQL Database screenshot (MySQL Database, and using HeidiSQL )
the specific example:
if I update/change the context Nordic as Nike from mySQL, by success connect both, the website part the Nike can replace Nordic as new topic
update -
now I'm sure the "django" and "MySQL" is connected
that I craete the 'TestModel' and 'TestModel_002' from django, will also added in MySQL
conclude:
"django" and "MySQL" is connected
still not reach my original issue , insert/update data in "MySQL" can affect website
https://imgur.com/a/f1CNGQ4
now the "django" and "MySQL" is connected, but I'm looking for insert/update data in "MySQL" can affect website, seems im close, but what shall I do though?

If you want to connect your django app to an existed DB, you should just edit your django settings.py and write this:
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'NAME': 'DB_NAME',
'USER': 'DB_USER',
'PASSWORD': 'DB_PASSWORD',
'HOST': 'localhost', # Or an IP Address that your DB is hosted on
'PORT': '3306',
}
}

Can't connect to Postgres from Django using a connection service file (on Windows)

[NOTE: This is using Django 4.0.2, Python 3.8.2, and Postgres 14.2.]
I have successfully set up Django and Postgres, and I can get them to work together when I put all of the Postgres parameters in the Django settings.py file. However, as shown in the Django documentation, I want to use a Postgres connection service file instead. I've created a service file (C:\Program Files\PostgreSQL\14\etc\pg_service.conf) that looks like this:
[test_svc_1]
host=localhost
user=django_admin
dbname=MyDbName
port=5432
Launching Postgres from the command line with this file seems to work fine, as it prompts me for the password:
> psql service=test_svc_1
Password for user django_admin:
However, when I try to make migrations with Django, I get the following error:
Traceback (most recent call last):
File "C:\...\django\db\backends\base\base.py", line 219, in ensure_connection
self.connect()
File "C:\...\django\utils\asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "C:\...\django\db\backends\base\base.py", line 200, in connect
self.connection = self.get_new_connection(conn_params)
File "C:\...\django\utils\asyncio.py", line 26, in inner
return func(*args, **kwargs)
File "C:\...\django\db\backends\postgresql\base.py", line 187, in get_new_connection
connection = Database.connect(**conn_params)
File "C:\Users\...\psycopg2\__init__.py",line 122, in connect
conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
psycopg2.OperationalError: definition of service "test_svc_1" not found
There were other exceptions related to this one, such as:
django.db.utils.OperationalError: definition of service "test_svc_1" not found
but they all pointed back to not finding the service "test_svc_1".
Here is an excerpt from my Django settings.py file. Adding the NAME parameter got me a little further along, but I shouldn't need to include it once Django(?) finds the connection service file.
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql',
'HOST': 'localhost',
'NAME': 'MyDbName',
'OPTIONS': {
'service': 'test_svc_1',
'passfile': '.my_pgpass',
},
},
}
Any thoughts as to what I'm missing? Worst case, I guess that I can revert to using environment variables and have the settings.py file refer to them. But I'd like to understand what I'm doing wrong rather than giving up.
Thanks for any guidance.

In case anyone runs across this question, I finally got it to work with service and password files thanks to some guidance from Ken Whitesell on the Django forum. Here is what I needed to do:
I had to create Windows environment variables for PGPASSFILE and PSERVICEFILE that point to the two files. I placed them both in C:\Program Files\PostgreSQL\14\etc, although I’m guessing that they can go into other directories as long as the environment variables point to them.
Next, I had to modify my database record in Django's settings.py as follows (which is different from what the Django docs specify):
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql',
'HOST': 'localhost',
'NAME': 'MyDbName',
'OPTIONS': {
'service': 'test_svc_1',
},
},
}
The service name in OPTIONS needs to match the service name in the PGSERVICEFILE.
Two differences from the Django docs:
I needed to include the database name.
I couldn’t get it to work with a ‘passfile’ entry in the OPTIONS dictionary, but it does work when I delete that. Perhaps I was doing something wrong, but I tried several different options and folders.
EDIT: Let me add some explanation points to avoid misunderstanding.
Django documentation is correct, but I would add one note about defining path on Windows (with forward slashes /) as they noted in other documents, where need to write path to file.
Your way above (without passfile key is working because you added PGPASSFILE environment variable and psycopg2 reads path from it.
But you can specify path to pgpass.conf directly (or retrieve it from environment variable, see commented line below).
Also DB host and DB name should be placed in .pg_service.conf file. See all parameter key words in PostgreSQL docs.
Considering this, the following files example should work (taking your settings values):
# C:\Program Files\PostgreSQL\14\etc\.pg_service.conf
[test_svc_1]
host=localhost
user=django_admin
dbname=MyDbName
port=5432
# Django `settings.py`
import os
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.postgresql',
'OPTIONS': {
'service': 'test_svc_1',
# 'passfile': os.getenv("PGPASSFILE"),
'passfile': "C:/Program Files/PostgreSQL/14/etc/pgpass.conf",
},
}
}
And of course, line with correct credentials in pgpass.conf must be present:
#hostname:port:database:username:password
localhost:5432:MyDbName:django_admin:your_secret

Turns out that the service name on the ~/.pg_service.conf file must be the database name, i.e: [djangodb] . After that it was not necessary to pass DBNAME. And the environment variable should call the service name only, not the file path. I also was having problems in Django 4 to find my env vars on the settings.py file with os.environ.get('VAR'). After changing to str(os.getenv('VAR')) things got smooth. Bye.

Using Process Monitor I found that the location of the file is in %APPDATA%\Roaming\postgresql\.pg_service.conf
Putting the file in that location didn't have any problems and I didn't have to set any system variables.
In the file I put the host, port, user and password and in django settings I only specified the database and the service.
The postgresql documentation is apparently not correct.

Django(djongo) can't connect to MondoDB Atlas after Heroku deployment

I managed to get it working locally (different cluster, separate settings.py), but not after when deployed to Heroku.
Heroku - automatically adds DATABASE_URL config var with a postgresql, and I cannot remove/edit it.
MongoDB Atlas - I've set the MongoDB Atlas cluster to allow IPs from everywhere. And the password has no funny characters.
django production settings.py
DATABASES = {
'default': {
'ENGINE': 'djongo',
'NAME': 'DBProd',
'CLIENT': {
'host': "mongodb+srv://XXX:YYY#ZZZ.pc4rx.mongodb.net/DBProd?retryWrites=true&w=majority",
}
}
}
I ran migrate straight after the deployment and it's all green OKs
heroku run python manage.py migrate
Everything works functional wise, just that the data are not stored in the MongoDB Atlas cluster. There are lots of posts from various sites on this, but they all have different instructions... Some of the posts I tried to follow:
https://developer.mongodb.com/how-to/use-atlas-on-heroku/
Django + Heroku + MongoDB Atlas (Djongo) = DatabaseError with No Exception
Connecting Heroku App to Atlas MongoDB Cloud service
-- A very confused beginner

For whoever lands on this. Add 'authMechanism': 'SCRAM-SHA-1', below 'host' will fix the issue.

This happened to me as well, in my case, somehow Heroku added postgresql as an add-on for my app so have to delete that first.
Check Heroku documentation about postgresql and how to destroy add-on:
https://devcenter.heroku.com/changelog-items/438
https://devcenter.heroku.com/articles/managing-add-ons
Then you need to configure MongoDB as your database by adding a MONGODB_URI config var with your database url. You should be ready to connect to your MongoDB now!
The following doc also helps:
https://www.mongodb.com/developer/how-to/use-atlas-on-heroku/

I've been having the same issue. Everything works fine locally. The problem is when deploying on Heroku. I have added 'authMechanism': 'SCRAM-SHA-1' and I have also configured MongoDB as my database by adding a MONGODB_URI config var. Heroku still autoconfigures DATABASE_URL config var with a postgresql, and I cannot remove/edit it.
In my Javascript code I used fetch('127.0.0.1:8000/<something>') which I specified in my urls.py and that way views.py read data from pymongo and returned it as a response.
After deploying my app to Heroku (and hardcoding the 127.0.0.1:8000 to <myappname>.heroku.com) the same fetch method seems to return [] instead of json containing values from MongoDB.
This is the most identical issue I found in a post I hope I'm not out of subject.

Trouble accessing Heroku's config vars with os.environ in Django/Python

I'm hosting a Django app on Heroku and I do not want my database credentials in the settings.py file to be visible in GitHub. Rather, I want them to be accessed in Heroku's config vars. Heroku's docs says it's possible to access the config vars in Python code like this:
from boto.s3.connection import S3Connection
s3 = S3Connection(os.environ['S3_KEY'], os.environ['S3_SECRET'])
So I set the relevant config vars like this:
heroku config:set PASSWORD=madeuppassword
And I tried to access the config vars in the source code like is says like this:
DATABASES = {
'default': {
'ENGINE': os.environ['ENGINE'],
'NAME': os.environ['NAME'],
'USER': os.environ['USER'],
'PORT': os.environ['PORT'],
'PASSWORD': os.environ['PASSWORD'],
'HOST': os.environ['HOST']
}
}
However when running the server I get this error in my command prompt:
raise KeyError(key) from None
KeyError: 'ENGINE'
To the best of my knowledge I set and accessed Heroku's config vars as it's demonstrated in their docs but I keep getting this error. What am I possibly doing wrong that it keeps bringing up this error?
Any help is appreciated!

How do I tell django to use --skip-secure-auth when connecting to mysql?

My django setup needs to connect to a mysql backend. I am getting the following error:
(2049, "Connection using old (pre-4.1.1) authentication protocol refused (client option 'secure_auth' enabled)")
Googling around tells my that that error means I need to use the ' --skip-secure-auth' command line switch. I can not find any way to get django to use this switch, or it's equivalent.
How can I do that? (or alternately what is the real problem, if I am way off base.)

Have you tried OPTIONS?
DATABASES = {
'default': {
'ENGINE': 'django.db.backends.mysql',
'OPTIONS': {
'secure-auth': False,
},
}
}
sources:
django documentation
mysql documentation