odwyersoftware/django-rename-app

A Django Management Command to rename existing Django Applications.

django-rename-app

A Django Management Command to rename existing Django Applications.

Installation

pip install django-rename-app.

Add to your Django settings.py INSTALLED_APPS:

INSTALLED_APPS = [
    ...
    'django_rename_app',
    ...
]

Usage

python manage.py rename_app <old_app_name> <new_app_name>

For full detailed instructions see https://odwyer.software/blog/how-to-rename-an-existing-django-application

django-rename-app's Issues

Don't attempt to rename table if it doesn't exist

Thanks for this package, it was a big help! One thing I noticed while trying to use it is that the following query was tripping up on models/tables that had been removed at some point from the original app:

query = (
    f'ALTER TABLE "{old_table_name}" '
    f'RENAME TO "{new_table_name}"'
)

Adding IF EXISTS to the query helped to skip tables that no longer exist.

query = (
    f'ALTER TABLE IF EXISTS "{old_table_name}" '
    f'RENAME TO "{new_table_name}"'
)

I can fork and submit a PR if you'd like.

[Bug] Handle truncation of long table names the same way Django does - Postgres

I had a table which would have had a name (after the app rename process) like:

asdfasd_contests_contesttrackattachmentrequirement_contest_track

which is 64 characters long.

As documented here, the default maximum table name for Postgres is 63 characters, so truncation is necessary: https://www.postgresql.org/docs/9.1/sql-syntax-lexical.html#:~:text=By%20default%2C%20NAMEDATALEN%20is%2064,in%20src%2Finclude%2Fpg_config_manual.

The name that I ended up with:
asdfasd_contests_contesttrackattachmentrequirement_contest_trac

How django truncates the table name:
asdfasd_contests_contesttrackattachmentrequirement_contest_7599

I'm looking into how this 7599 is determined - probably just a hash algo.

Rename permissions in auth_permissions table

I think it will be good to update the existing rows name and codename columns in auth_permissions table.

Not renaming id_seq sequences ?

I have some leftover id_seq sequences having the old prefix - is this the expected behavior?

Print only SQL commands

Hi @odwyersoftware, thank you for this package, it really helped me.

A nice feature would be just print the commands to the console and then we can simply copy & paste instead of adding it to requirements/building docker image/etc.

I can add this feature if you accept it.

Unable to rename tables when they contain uppercase letters

Renaming does not seem possible when a table name contains upper case letters; i.e. psycopg2 doesn't seem to properly handle that case, even so you pass the name within double quotes to the rename_app call:

# python3 manage.py rename_app  "MyProject" "myproject"
Renaming MyProject to myproject
models: {'team': <class 'myproject.models.Team'>, 'topic': <class 'myproject.models.Topic'>, 'mode': <class 'myproject.models.Mode'>}
renaming team table from: MyProject_team to: myproject_team.
Rename query failed: "ALTER TABLE MyProject_team RENAME TO myproject_team"
Traceback (most recent call last):
  File "/usr/local/lib/python3.9/site-packages/django/db/backends/utils.py", line 87, in _execute
    return self.cursor.execute(sql)
psycopg2.errors.UndefinedTable: relation "myproject_team" does not exist

Fixed by: #9

Table indices are not included in rename process.

HEY!

Hey, you're still active on Github, update ur Mega.NZ Lib!
Please...

model_name not defined

Here is the error from line 79:
f"Renaming {model_name} table from: {old_table_name} to: {new_table_name}." NameError: name 'model_name' is not defined