zulip/zerver/migrations/0375_invalid_characters_in_...

85 lines
2.8 KiB
Python

import unicodedata
from django.db import connection, migrations
from django.db.backends.base.schema import BaseDatabaseSchemaEditor
from django.db.migrations.state import StateApps
# There are 66 Unicode non-characters; see
# https://www.unicode.org/faq/private_use.html#nonchar4
unicode_non_chars = {
chr(x)
for r in [
range(0xFDD0, 0xFDF0), # FDD0 through FDEF, inclusive
range(0xFFFE, 0x110000, 0x10000), # 0xFFFE, 0x1FFFE, ... 0x10FFFE inclusive
range(0xFFFF, 0x110000, 0x10000), # 0xFFFF, 0x1FFFF, ... 0x10FFFF inclusive
]
for x in r
}
def character_is_printable(character: str) -> bool:
return not (unicodedata.category(character) in ["Cc", "Cs"] or character in unicode_non_chars)
def fix_stream_names(apps: StateApps, schema_editor: BaseDatabaseSchemaEditor) -> None:
Stream = apps.get_model("zerver", "Stream")
Realm = apps.get_model("zerver", "Realm")
total_fixed_count = 0
realm_ids = Realm.objects.values_list("id", flat=True)
if len(realm_ids) == 0:
return
print()
for realm_id in realm_ids:
print(f"Processing realm {realm_id}")
realm_stream_dicts = Stream.objects.filter(realm_id=realm_id).values("id", "name")
occupied_stream_names = {stream_dict["name"] for stream_dict in realm_stream_dicts}
for stream_dict in realm_stream_dicts:
stream_name = stream_dict["name"]
fixed_stream_name = "".join(
[
character if character_is_printable(character) else "\N{REPLACEMENT CHARACTER}"
for character in stream_name
]
)
if fixed_stream_name == stream_name:
continue
if fixed_stream_name == "":
fixed_stream_name = "(no name)"
# The process of stripping invalid characters can lead to collisions,
# with the new stream name being the same as the name of another existing stream.
# We append underscore until the name no longer conflicts.
while fixed_stream_name in occupied_stream_names:
fixed_stream_name += "_"
occupied_stream_names.add(fixed_stream_name)
total_fixed_count += 1
with connection.cursor() as cursor:
cursor.execute(
"UPDATE zerver_stream SET name = %s WHERE id = %s",
[fixed_stream_name, stream_dict["id"]],
)
print(f"Fixed {total_fixed_count} stream names")
class Migration(migrations.Migration):
atomic = False
dependencies = [
("zerver", "0374_backfill_user_delete_realmauditlog"),
]
operations = [
migrations.RunPython(
fix_stream_names,
reverse_code=migrations.RunPython.noop,
elidable=True,
),
]