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Diffstat (limited to '.venv/lib/python3.12/site-packages/alembic/templates/multidb/env.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/alembic/templates/multidb/env.py | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/alembic/templates/multidb/env.py b/.venv/lib/python3.12/site-packages/alembic/templates/multidb/env.py new file mode 100644 index 00000000..e937b64e --- /dev/null +++ b/.venv/lib/python3.12/site-packages/alembic/templates/multidb/env.py @@ -0,0 +1,140 @@ +import logging +from logging.config import fileConfig +import re + +from sqlalchemy import engine_from_config +from sqlalchemy import pool + +from alembic import context + +USE_TWOPHASE = False + +# this is the Alembic Config object, which provides +# access to the values within the .ini file in use. +config = context.config + +# Interpret the config file for Python logging. +# This line sets up loggers basically. +if config.config_file_name is not None: + fileConfig(config.config_file_name) +logger = logging.getLogger("alembic.env") + +# gather section names referring to different +# databases. These are named "engine1", "engine2" +# in the sample .ini file. +db_names = config.get_main_option("databases", "") + +# add your model's MetaData objects here +# for 'autogenerate' support. These must be set +# up to hold just those tables targeting a +# particular database. table.tometadata() may be +# helpful here in case a "copy" of +# a MetaData is needed. +# from myapp import mymodel +# target_metadata = { +# 'engine1':mymodel.metadata1, +# 'engine2':mymodel.metadata2 +# } +target_metadata = {} + +# other values from the config, defined by the needs of env.py, +# can be acquired: +# my_important_option = config.get_main_option("my_important_option") +# ... etc. + + +def run_migrations_offline() -> None: + """Run migrations in 'offline' mode. + + This configures the context with just a URL + and not an Engine, though an Engine is acceptable + here as well. By skipping the Engine creation + we don't even need a DBAPI to be available. + + Calls to context.execute() here emit the given string to the + script output. + + """ + # for the --sql use case, run migrations for each URL into + # individual files. + + engines = {} + for name in re.split(r",\s*", db_names): + engines[name] = rec = {} + rec["url"] = context.config.get_section_option(name, "sqlalchemy.url") + + for name, rec in engines.items(): + logger.info("Migrating database %s" % name) + file_ = "%s.sql" % name + logger.info("Writing output to %s" % file_) + with open(file_, "w") as buffer: + context.configure( + url=rec["url"], + output_buffer=buffer, + target_metadata=target_metadata.get(name), + literal_binds=True, + dialect_opts={"paramstyle": "named"}, + ) + with context.begin_transaction(): + context.run_migrations(engine_name=name) + + +def run_migrations_online() -> None: + """Run migrations in 'online' mode. + + In this scenario we need to create an Engine + and associate a connection with the context. + + """ + + # for the direct-to-DB use case, start a transaction on all + # engines, then run all migrations, then commit all transactions. + + engines = {} + for name in re.split(r",\s*", db_names): + engines[name] = rec = {} + rec["engine"] = engine_from_config( + context.config.get_section(name, {}), + prefix="sqlalchemy.", + poolclass=pool.NullPool, + ) + + for name, rec in engines.items(): + engine = rec["engine"] + rec["connection"] = conn = engine.connect() + + if USE_TWOPHASE: + rec["transaction"] = conn.begin_twophase() + else: + rec["transaction"] = conn.begin() + + try: + for name, rec in engines.items(): + logger.info("Migrating database %s" % name) + context.configure( + connection=rec["connection"], + upgrade_token="%s_upgrades" % name, + downgrade_token="%s_downgrades" % name, + target_metadata=target_metadata.get(name), + ) + context.run_migrations(engine_name=name) + + if USE_TWOPHASE: + for rec in engines.values(): + rec["transaction"].prepare() + + for rec in engines.values(): + rec["transaction"].commit() + except: + for rec in engines.values(): + rec["transaction"].rollback() + raise + finally: + for rec in engines.values(): + rec["connection"].close() + + +if context.is_offline_mode(): + run_migrations_offline() +else: + run_migrations_online() |