Fix and update alembic env and ini (#474)

Author: wu-clan

backend/alembic.ini

@@ -1,26 +1,27 @@
 # A generic, single database configuration.
 
 [alembic]
-# path to migration scripts
+# path to migration scripts.
+# Use forward slashes (/) also on windows to provide an os agnostic path
 script_location = alembic
 
-# template used to generate migration files
-file_template = %%(year)d-%%(month).2d-%%(day).2d_%%(hour).2d-%%(minute).2d_%%(rev)s_%%(slug)s
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+file_template = %%(year)d-%%(month).2d-%%(day).2d-%%(hour).2d:%%(minute).2d:%%(second).2d-%%(rev)s_%%(slug)s
 
 # sys.path path, will be prepended to sys.path if present.
 # defaults to the current working directory.
 prepend_sys_path = .
 
 # timezone to use when rendering the date within the migration file
 # as well as the filename.
-# If specified, requires the python-dateutil library that can be
-# installed by adding `alembic[tz]` to the pip requirements
-# string value is passed to dateutil.tz.gettz()
+# If specified, requires the python>=3.9 or backports.zoneinfo library.
+# Any required deps can installed by adding `alembic[tz]` to the pip requirements
+# string value is passed to ZoneInfo()
 # leave blank for localtime
 # timezone =
 
-# max length of characters to apply to the
-# "slug" field
+# max length of characters to apply to the "slug" field
 # truncate_slug_length = 40
 
 # set to 'true' to run the environment during
@@ -35,16 +36,24 @@ prepend_sys_path = .
 # version location specification; This defaults
 # to alembic/versions.  When using multiple version
 # directories, initial revisions must be specified with --version-path.
-# The path separator used here should be the separator specified by "version_path_separator"
+# The path separator used here should be the separator specified by "version_path_separator" below.
 # version_locations = %(here)s/bar:%(here)s/bat:alembic/versions
 
 # version path separator; As mentioned above, this is the character used to split
-# version_locations. Valid values are:
+# version_locations. The default within new alembic.ini files is "os", which uses os.pathsep.
+# If this key is omitted entirely, it falls back to the legacy behavior of splitting on spaces and/or commas.
+# Valid values for version_path_separator are:
 #
 # version_path_separator = :
 # version_path_separator = ;
 # version_path_separator = space
-version_path_separator = os  # default: use os.pathsep
+# version_path_separator = newline
+version_path_separator = os  # Use os.pathsep. Default configuration used for new projects.
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
 
 # the output encoding used when revision files
 # are written from script.py.mako
@@ -64,6 +73,12 @@ sqlalchemy.url = driver://user:pass@localhost/dbname
 # black.entrypoint = black
 # black.options = -l 79 REVISION_SCRIPT_FILENAME
 
+# lint with attempts to fix using "ruff" - use the exec runner, execute a binary
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = %(here)s/.venv/bin/ruff
+# ruff.options = --fix REVISION_SCRIPT_FILENAME
+
 # Logging configuration
 [loggers]
 keys = root,sqlalchemy,alembic

backend/alembic/env.py

@@ -1,45 +1,44 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
-# ruff: noqa: E402, F403, I001, RUF100
+# ruff: noqa: F403, F401, I001, RUF100
 import asyncio
 import os
 import sys
-
 from logging.config import fileConfig
 
 from alembic import context
-from sqlalchemy import engine_from_config, pool
-from sqlalchemy.ext.asyncio import AsyncEngine
+from sqlalchemy import pool
+from sqlalchemy.engine import Connection
+from sqlalchemy.ext.asyncio import async_engine_from_config
 
 sys.path.append('../')
 
+from backend.common.model import MappedBase
 from backend.core import path_conf
+from backend.database.db_mysql import SQLALCHEMY_DATABASE_URL
+
+# import your new model here
+from backend.app.admin.model import *  # noqa: F401
+from backend.app.generator.model import *  # noqa: F401
 
-if not os.path.exists(path_conf.ALEMBIC_Versions_DIR):
-    os.makedirs(path_conf.ALEMBIC_Versions_DIR)
+if not os.path.exists(path_conf.ALEMBIC_VERSION_DIR):
+    os.makedirs(path_conf.ALEMBIC_VERSION_DIR)
 
 # this is the Alembic Config object, which provides
 # access to the values within the .ini file in use.
-config = context.config
+alembic_config = context.config
 
 # Interpret the config file for Python logging.
 # This line sets up loggers basically.
-fileConfig(config.config_file_name)
+if alembic_config.config_file_name is not None:
+    fileConfig(alembic_config.config_file_name)
 
-# add your model's MetaData object here
+# model's MetaData object
 # for 'autogenerate' support
-from backend.common.model import MappedBase
-
-# if add new app, do like this
-from backend.app.admin.model import *  # noqa: F401
-from backend.app.generator.model import *  # noqa: F401
-
 target_metadata = MappedBase.metadata
 
 # other values from the config, defined by the needs of env.py,
-from backend.database.db_mysql import SQLALCHEMY_DATABASE_URL
-
-config.set_main_option('sqlalchemy.url', SQLALCHEMY_DATABASE_URL)
+alembic_config.set_main_option('sqlalchemy.url', SQLALCHEMY_DATABASE_URL)
 
 
 def run_migrations_offline():
@@ -54,49 +53,68 @@ def run_migrations_offline():
     script output.
 
     """
-    url = config.get_main_option('sqlalchemy.url')
+    url = alembic_config.get_main_option('sqlalchemy.url')
     context.configure(
         url=url,
         target_metadata=target_metadata,
         literal_binds=True,
         dialect_opts={'paramstyle': 'named'},
+        compare_type=True,
+        compare_server_default=True,
+        transaction_per_migration=True,
     )
 
     with context.begin_transaction():
         context.run_migrations()
 
 
-def do_run_migrations(connection):
+def do_run_migrations(connection: Connection) -> None:
+    # 当迁移无变化时，不生成迁移记录
+    def process_revision_directives(context, revision, directives):
+        if alembic_config.cmd_opts.autogenerate:
+            script = directives[0]
+            if script.upgrade_ops.is_empty():
+                directives[:] = []
+                print('\nNo changes in model detected')
+
     context.configure(
         connection=connection,
         target_metadata=target_metadata,
+        compare_type=True,
+        compare_server_default=True,
+        transaction_per_migration=True,
+        process_revision_directives=process_revision_directives,
     )
 
     with context.begin_transaction():
         context.run_migrations()
 
 
-async def run_migrations_online():
-    """Run migrations in 'online' mode.
-
-    In this scenario we need to create an Engine
+async def run_async_migrations() -> None:
+    """In this scenario we need to create an Engine
     and associate a connection with the context.
 
     """
-    connectable = AsyncEngine(
-        engine_from_config(
-            config.get_section(config.config_ini_section),
-            prefix='sqlalchemy.',
-            poolclass=pool.NullPool,
-            future=True,
-        )
+
+    connectable = async_engine_from_config(
+        alembic_config.get_section(alembic_config.config_ini_section, {}),
+        prefix='sqlalchemy.',
+        poolclass=pool.NullPool,
     )
 
     async with connectable.connect() as connection:
         await connection.run_sync(do_run_migrations)
 
+    await connectable.dispose()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode."""
+
+    asyncio.run(run_async_migrations())
+
 
 if context.is_offline_mode():
     run_migrations_offline()
 else:
-    asyncio.run(run_migrations_online())
+    run_migrations_online()

backend/core/path_conf.py

@@ -9,7 +9,7 @@
 BasePath = Path(__file__).resolve().parent.parent
 
 # alembic 迁移文件存放路径
-ALEMBIC_Versions_DIR = os.path.join(BasePath, 'alembic', 'versions')
+ALEMBIC_VERSION_DIR = os.path.join(BasePath, 'alembic', 'versions')
 
 # 日志文件路径
 LOG_DIR = os.path.join(BasePath, 'log')