Merge pull request #4450 from smotornyuk/alembic

sqlalchemy-migrate -> Alembic

.gitignore

@@ -23,6 +23,7 @@ tmp/*
 solr_runtime/*
 fl_notes.txt
 *.ini
+!ckan/migration/alembic.ini
 .noseids
 *~
 .idea

ckan/cli/db.py

@@ -1,7 +1,8 @@
 # encoding: utf-8
 
+import os
 import logging
-
+import ckan.migration as migration_repo
 import click
 
 from ckan.cli import error_shout
@@ -44,8 +45,8 @@ def cleandb():
 
 
 @db.command(u'upgrade', short_help=u'Upgrade the database')
-@click.option(u'-v', u'--version', help=u'Migration version')
-def updatedb(version=None):
+@click.option(u'-v', u'--version', help=u'Migration version', default=u'head')
+def updatedb(version):
     u'''Upgrading the database'''
     try:
         import ckan.model as model
@@ -56,17 +57,49 @@ def updatedb(version=None):
         click.secho(u'Upgrading DB: SUCCESS', fg=u'green', bold=True)
 
 
-@db.command(u'version', short_help=u'Returns current version of data schema')
-def version():
-    u'''Return current version'''
-    log.info(u"Returning current DB version")
+@db.command(u'downgrade', short_help=u'Downgrade the database')
+@click.option(u'-v', u'--version', help=u'Migration version', default=u'base')
+def downgradedb(version):
+    u'''Downgrading the database'''
     try:
-        from ckan.model import Session
-        ver = Session.execute(u'select version from '
-                              u'migrate_version;').fetchall()
-        click.secho(
-            u"Latest data schema version: {0}".format(ver[0][0]),
-            bold=True
-        )
+        import ckan.model as model
+        model.repo.downgrade_db(version)
     except Exception as e:
         error_shout(e)
+    else:
+        click.secho(u'Downgrading DB: SUCCESS', fg=u'green', bold=True)
+
+
+@db.command(u'version', short_help=u'Returns current version of data schema')
+@click.option(u'--hash', is_flag=True)
+def version(hash):
+    u'''Return current version'''
+    log.info(u"Returning current DB version")
+    import ckan.model as model
+    model.repo.setup_migration_version_control()
+    current = model.repo.current_version()
+    if not hash:
+        current = _version_hash_to_ordinal(current)
+    click.secho(
+        u'Current DB version: {}'.format(current),
+        fg=u'green', bold=True
+    )
+
+
+def _version_hash_to_ordinal(version):
+    if u'base' == version:
+        return 0
+    versions_dir = os.path.join(
+        os.path.dirname(migration_repo.__file__), u'versions'
+    )
+    versions = sorted(os.listdir(versions_dir))
+
+    # latest version looks like `123abc (head)`
+    if version.endswith(u'(head)'):
+        return int(versions[-1].split(u'_')[0])
+    for name in versions:
+        if version in name:
+            return int(name.split(u'_')[0])
+    error_shout(u'Version `{}` was not found in {}'.format(
+        version, versions_dir
+    ))

ckan/lib/cli.py

@@ -351,7 +351,8 @@ class ManageDb(CkanCommand):
     def command(self):
         cmd = self.args[0]
 
-        self._load_config(cmd!='upgrade')
+        self._load_config(cmd != 'upgrade')
+
         import ckan.model as model
         import ckan.lib.search as search
 
@@ -375,10 +376,9 @@ def command(self):
             if self.verbose:
                 print('Cleaning DB: SUCCESS')
         elif cmd == 'upgrade':
-            if len(self.args) > 1:
-                model.repo.upgrade_db(self.args[1])
-            else:
-                model.repo.upgrade_db()
+            model.repo.upgrade_db(*self.args[1:])
+        elif cmd == 'downgrade':
+            model.repo.downgrade_db(*self.args[1:])
         elif cmd == 'version':
             self.version()
         elif cmd == 'create-from-model':

ckan/migration/README

@@ -1,4 +1 @@
-This is a database migration repository.
-
-More information at
-http://code.google.com/p/sqlalchemy-migrate/
+Generic single-database configuration.

ckan/migration/__init__.py

@@ -0,0 +1,22 @@
+# encoding: utf-8
+
+
+def skip_based_on_legacy_engine_version(op, filename):
+    u'''Safe way to update instances sqlalchemy-migrate migrations applied.
+
+    CKAN `db upgrade/init` command is trying to obtain current version
+    of sqlalchemy-migrate migrations from database. In that case, we
+    are going to compare existing version from DB with alembic
+    migration script's prefix in filename which defines corresponding
+    version of sqlalchemy-migrate script.  We need this, because
+    alembic uses string ids instead of incremental numbers for
+    identifying current migration version. If alembic script's version
+    is less than version of currently applied sqlalchemy migration,
+    than it just marked as applied, but no SQL queries will be
+    actually executed. Thus there are no difference between updating
+    existing portals and initializing new ones.
+    '''
+    conf = op.get_context().config
+    version = conf.get_main_option(u'sqlalchemy_migrate_version')
+    if version:
+        return int(version) >= int(filename.split(u'_', 1)[0])

ckan/migration/alembic.ini

@@ -0,0 +1,82 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = .
+
+# template used to generate migration files
+# file_template = %%(rev)s_%%(slug)s
+
+# timezone to use when rendering the date
+# within the migration file as well as the filename.
+# string value is passed to dateutil.tz.gettz()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+#truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; this defaults
+# to ckan/migration/alembic/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path
+# version_locations = %(here)s/bar %(here)s/bat ckan/migration/alembic/versions
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+# This value does not affects CKAN commands, but developers are able
+# to execute alembic commands(i.e. `alembic heads`, `alembic
+# revision`) directly from this folder with line bellow. If it
+# configured to correct values, migrations can even be applied(but it
+# strongly discouraged - use CKAN's upgrade command instead). This
+# functionality is considered as internal, so don't rely on it,
+# because it may be removed in future. Use official CKAN commands
+# rather than direct interactions with alembic
+sqlalchemy.url = postgresql://ckan_default:pass@localhost/ckan_default
+
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

ckan/migration/env.py

@@ -0,0 +1,75 @@
+# encoding: utf-8
+
+from __future__ import with_statement
+from alembic import context
+from sqlalchemy import engine_from_config, pool
+# from logging.config import fileConfig
+from ckan.model import init_model
+from ckan.model.meta import metadata
+
+# 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.
+# fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+target_metadata = 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():
+    """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.
+
+    """
+    url = config.get_main_option(u"sqlalchemy.url")
+    context.configure(
+        url=url, target_metadata=target_metadata, literal_binds=True
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online():
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section),
+        prefix=u'sqlalchemy.',
+        poolclass=pool.NullPool
+    )
+    connection = connectable.connect()
+    init_model(connection)
+
+    context.configure(connection=connection, target_metadata=target_metadata)
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

ckan/migration/script.py.mako

@@ -0,0 +1,24 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+branch_labels = ${repr(branch_labels)}
+depends_on = ${repr(depends_on)}
+
+
+def upgrade():
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade():
+    ${downgrades if downgrades else "pass"}