mirror of https://gitlab.com/litecord/litecord.git
144 lines
3.7 KiB
Python
144 lines
3.7 KiB
Python
import inspect
|
|
from pathlib import Path
|
|
from dataclasses import dataclass
|
|
from collections import namedtuple
|
|
from typing import Dict
|
|
|
|
import asyncpg
|
|
from logbook import Logger
|
|
|
|
log = Logger(__name__)
|
|
|
|
|
|
Migration = namedtuple('Migration', 'id name path')
|
|
|
|
|
|
@dataclass
|
|
class MigrationContext:
|
|
"""Hold information about migration."""
|
|
migration_folder: Path
|
|
scripts: Dict[int, Migration]
|
|
|
|
@property
|
|
def latest(self):
|
|
"""Return the latest migration ID."""
|
|
return max(self.scripts.keys())
|
|
|
|
|
|
def make_migration_ctx() -> MigrationContext:
|
|
"""Create the MigrationContext instance."""
|
|
# taken from https://stackoverflow.com/a/6628348
|
|
script_path = inspect.stack()[0][1]
|
|
script_folder = '/'.join(script_path.split('/')[:-1])
|
|
script_folder = Path(script_folder)
|
|
|
|
migration_folder = script_folder / 'scripts'
|
|
|
|
mctx = MigrationContext(migration_folder, {})
|
|
|
|
for mig_path in migration_folder.glob('*.sql'):
|
|
mig_path_str = str(mig_path)
|
|
|
|
# extract migration script id and name
|
|
mig_filename = mig_path_str.split('/')[-1].split('.')[0]
|
|
name_fragments = mig_filename.split('_')
|
|
|
|
mig_id = int(name_fragments[0])
|
|
mig_name = '_'.join(name_fragments[1:])
|
|
|
|
mctx.scripts[mig_id] = Migration(
|
|
mig_id, mig_name, mig_path)
|
|
|
|
return mctx
|
|
|
|
|
|
async def _ensure_changelog(app, ctx):
|
|
# make sure we have the migration table up
|
|
|
|
try:
|
|
await app.db.execute("""
|
|
CREATE TABLE migration_log (
|
|
change_num bigint NOT NULL,
|
|
|
|
apply_ts timestamp without time zone default
|
|
(now() at time zone 'utc'),
|
|
|
|
description text,
|
|
|
|
PRIMARY KEY (change_num)
|
|
);
|
|
""")
|
|
|
|
# if we were able to create the
|
|
# migration_log table, insert that we are
|
|
# on the latest version.
|
|
await app.db.execute("""
|
|
INSERT INTO migration_log (change_num, description)
|
|
VALUES ($1, $2)
|
|
""", ctx.latest, 'migration setup')
|
|
except asyncpg.DuplicateTableError:
|
|
log.debug('existing migration table')
|
|
|
|
|
|
async def apply_migration(app, migration: Migration):
|
|
"""Apply a single migration."""
|
|
migration_sql = migration.path.read_text(encoding='utf-8')
|
|
|
|
try:
|
|
await app.db.execute("""
|
|
INSERT INTO migration_log (change_num, description)
|
|
VALUES ($1, $2)
|
|
""", migration.id, f'migration: {migration.name}')
|
|
except asyncpg.UniqueViolationError:
|
|
log.warning('already applied {}', migration.id)
|
|
return
|
|
|
|
await app.db.execute(migration_sql)
|
|
log.info('applied {}', migration.id)
|
|
|
|
|
|
async def migrate_cmd(app, _args):
|
|
"""Main migration command.
|
|
|
|
This makes sure the database
|
|
is updated.
|
|
"""
|
|
|
|
ctx = make_migration_ctx()
|
|
|
|
await _ensure_changelog(app, ctx)
|
|
|
|
# local point in the changelog
|
|
local_change = await app.db.fetchval("""
|
|
SELECT max(change_num)
|
|
FROM migration_log
|
|
""")
|
|
|
|
local_change = local_change or 0
|
|
latest_change = ctx.latest
|
|
|
|
log.debug('local: {}, latest: {}', local_change, latest_change)
|
|
|
|
if local_change == latest_change:
|
|
print('no changes to do, exiting')
|
|
return
|
|
|
|
# we do local_change + 1 so we start from the
|
|
# next migration to do, end in latest_change + 1
|
|
# because of how range() works.
|
|
for idx in range(local_change + 1, latest_change + 1):
|
|
migration = ctx.scripts.get(idx)
|
|
|
|
print('applying', migration.id, migration.name)
|
|
await apply_migration(app, migration)
|
|
|
|
|
|
def setup(subparser):
|
|
migrate_parser = subparser.add_parser(
|
|
'migrate',
|
|
help='Run migration tasks',
|
|
description=migrate_cmd.__doc__
|
|
)
|
|
|
|
migrate_parser.set_defaults(func=migrate_cmd)
|