Simplify the future of our migration history

src/pretix/base/management/commands/makemigrations.py

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+"""
+Django, for theoretically very valid reasons, creates migrations for *every single thing*
+we change on a model. Even the `help_text`! This makes sense, as we don't know if any
+database backend unknown to us might actually use this information for its database schema.
+
+However, pretix only supports PostgreSQL, MySQL, MariaDB and SQLite and we can be pretty
+certain that some changes to models will never require a change to the database. In this case,
+not creating a migration for certain changes will save us some performance while applying them
+*and* allow for a cleaner git history. Win-win!
+
+Only caveat is that we need to do some dirty monkeypatching to achieve it...
+"""
+from django.core.management.commands.makemigrations import Command as Parent
+from django.db import models
+from django.db.migrations.operations import models as modelops
+from django_countries.fields import CountryField
+
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("verbose_name")
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("verbose_name_plural")
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("ordering")
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("get_latest_by")
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("default_manager_name")
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("permissions")
+modelops.AlterModelOptions.ALTER_OPTION_KEYS.remove("default_permissions")
+IGNORED_ATTRS = [
+    # (field type, attribute name, blacklist of field sub-types)
+    (models.Field, 'verbose_name', []),
+    (models.Field, 'help_text', []),
+    (models.Field, 'validators', []),
+    (models.Field, 'editable', [models.DateField, models.DateTimeField, models.DateField, models.BinaryField]),
+    (models.Field, 'blank', [models.DateField, models.DateTimeField, models.AutoField, models.NullBooleanField,
+                             models.TimeField]),
+    (models.CharField, 'choices', [CountryField])
+]
+
+original_deconstruct = models.Field.deconstruct
+
+
+def new_deconstruct(self):
+    name, path, args, kwargs = original_deconstruct(self)
+    for ftype, attr, blacklist in IGNORED_ATTRS:
+        if isinstance(self, ftype) and not any(isinstance(self, ft) for ft in blacklist):
+            kwargs.pop(attr, None)
+    return name, path, args, kwargs
+
+
+models.Field.deconstruct = new_deconstruct
+
+
+class Command(Parent):
+    pass

src/pretix/base/management/commands/migrate.py

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+"""
+Django tries to be helpful by suggesting to run "makemigrations" in red font on every "migrate"
+run when there are things we have no migrations for. Usually, this is intended, and running
+"makemigrations" can really screw up the environment of a user, so we want to prevent novice
+users from doing that by going really dirty and fitlering it from the output.
+"""
+import sys
+
+from django.core.management.base import OutputWrapper
+from django.core.management.commands.migrate import Command as Parent
+
+
+class OutputFilter(OutputWrapper):
+    blacklist = (
+        "Your models have changes that are not yet reflected",
+        "Run 'manage.py makemigrations' to make new "
+    )
+
+    def write(self, msg, style_func=None, ending=None):
+        if any(b in msg for b in self.blacklist):
+            return
+        super().write(msg, style_func, ending)
+
+
+class Command(Parent):
+    def __init__(self, stdout=None, stderr=None, no_color=False, force_color=False):
+        super().__init__(stdout, stderr, no_color, force_color)
+        self.stdout = OutputFilter(stdout or sys.stdout)