Part 2 of https://github.com/google/adk-python/discussions/3605.
The DatabaseSessionService now checks for the usage of a V1 schema based on the "adk_internal_metadata" table. Table creation and subsequent operations use either the V0 or V1 SQLAlchemy models accordingly. New databases will default to V1.
Migration script and CLI command will be provided in the next change.
Co-authored-by: Liang Wu <wuliang@google.com>
PiperOrigin-RevId: 845443406
Also provide a command line tool `adk migrate session` for DB migration
Addresses https://github.com/google/adk-python/discussions/3605
Addresses https://github.com/google/adk-python/issues/3681
To verify:
```
# Start one postgres DB
docker run --name my-postgres -d -e POSTGRES_DB=agent -e POSTGRES_USER=agent -e POSTGRES_PASSWORD=agent -e PGDATA=/var/lib/postgresql/data/pgdata -v pgvolume:/var/lib/postgresql/data -p 5532:5432 postgres
# Connect to an old version of ADK and produce some query data
adk web --session_service_uri=postgresql://agent:agent@localhost:5532/agent
# Check out to the latest branch and restart ADK web
# You should see error log ask you to migrate the DB
# Start a new DB
docker run --name migration-test-db \
-d \ --rm \ -e POSTGRES_DB=agent \ -e POSTGRES_USER=agent \ -e POSTGRES_PASSWORD=agent -e PGDATA=/var/lib/postgresql/data/pgdata -v migration_test_vol:/var/lib/postgresql/data -p 5533:5432 postgres
# DB Migration
adk migrate session \
--source_db_url="postgresql://agent:agent@localhost:5532/agent" \
--dest_db_url="postgresql://agent:agent@localhost:5533/agent"
# Run ADK web with the new DB
adk web --session_service_uri=postgresql+asyncpg://agent:agent@localhost:5533/agent
# You should see the data from old DB is migrated
```
Co-authored-by: Shangjie Chen <deanchen@google.com>
PiperOrigin-RevId: 837341139
George WealeandCopybara-Service
Liang WuandCopybara-Service
Shangjie ChenandCopybara-Service