sqlalchemy-migrate/migrate/versioning/version.py

283 lines
8.7 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
import os
import re
import shutil
import logging
from migrate import exceptions
from migrate.versioning import pathed, script
from datetime import datetime
import six
log = logging.getLogger(__name__)
class VerNum(object):
"""A version number that behaves like a string and int at the same time"""
_instances = dict()
def __new__(cls, value):
val = str(value)
if val not in cls._instances:
cls._instances[val] = super(VerNum, cls).__new__(cls)
ret = cls._instances[val]
return ret
def __init__(self,value):
self.value = str(int(value))
if self < 0:
raise ValueError("Version number cannot be negative")
def __add__(self, value):
ret = int(self) + int(value)
return VerNum(ret)
def __sub__(self, value):
return self + (int(value) * -1)
def __eq__(self, value):
return int(self) == int(value)
def __ne__(self, value):
return int(self) != int(value)
def __lt__(self, value):
return int(self) < int(value)
def __gt__(self, value):
return int(self) > int(value)
def __ge__(self, value):
return int(self) >= int(value)
def __le__(self, value):
return int(self) <= int(value)
def __repr__(self):
return "<VerNum(%s)>" % self.value
def __str__(self):
return str(self.value)
def __int__(self):
return int(self.value)
def __index__(self):
return int(self.value)
if six.PY3:
def __hash__(self):
return hash(self.value)
class Collection(pathed.Pathed):
"""A collection of versioning scripts in a repository"""
FILENAME_WITH_VERSION = re.compile(r'^(\d{3,}).*')
def __init__(self, path):
"""Collect current version scripts in repository
and store them in self.versions
"""
super(Collection, self).__init__(path)
# Create temporary list of files, allowing skipped version numbers.
files = os.listdir(path)
if '1' in files:
# deprecation
raise Exception('It looks like you have a repository in the old '
'format (with directories for each version). '
'Please convert repository before proceeding.')
tempVersions = dict()
for filename in files:
match = self.FILENAME_WITH_VERSION.match(filename)
if match:
num = int(match.group(1))
tempVersions.setdefault(num, []).append(filename)
else:
pass # Must be a helper file or something, let's ignore it.
# Create the versions member where the keys
# are VerNum's and the values are Version's.
self.versions = dict()
for num, files in tempVersions.items():
self.versions[VerNum(num)] = Version(num, path, files)
@property
def latest(self):
""":returns: Latest version in Collection"""
return max([VerNum(0)] + list(self.versions.keys()))
def _next_ver_num(self, use_timestamp_numbering):
if use_timestamp_numbering == True:
return VerNum(int(datetime.utcnow().strftime('%Y%m%d%H%M%S')))
else:
return self.latest + 1
def create_new_python_version(self, description, **k):
"""Create Python files for new version"""
ver = self._next_ver_num(k.pop('use_timestamp_numbering', False))
extra = str_to_filename(description)
if extra:
if extra == '_':
extra = ''
elif not extra.startswith('_'):
extra = '_%s' % extra
filename = '%03d%s.py' % (ver, extra)
filepath = self._version_path(filename)
script.PythonScript.create(filepath, **k)
self.versions[ver] = Version(ver, self.path, [filename])
def create_new_sql_version(self, database, description, **k):
"""Create SQL files for new version"""
ver = self._next_ver_num(k.pop('use_timestamp_numbering', False))
self.versions[ver] = Version(ver, self.path, [])
extra = str_to_filename(description)
if extra:
if extra == '_':
extra = ''
elif not extra.startswith('_'):
extra = '_%s' % extra
# Create new files.
for op in ('upgrade', 'downgrade'):
filename = '%03d%s_%s_%s.sql' % (ver, extra, database, op)
filepath = self._version_path(filename)
script.SqlScript.create(filepath, **k)
self.versions[ver].add_script(filepath)
def version(self, vernum=None):
"""Returns required version.
If vernum is not given latest version will be returned otherwise
required version will be returned.
:raises: : exceptions.VersionNotFoundError if respective migration
script file of version is not present in the migration repository.
"""
if vernum is None:
vernum = self.latest
try:
return self.versions[VerNum(vernum)]
except KeyError:
raise exceptions.VersionNotFoundError(
("Database schema file with version %(args)s doesn't "
"exist.") % {'args': VerNum(vernum)})
@classmethod
def clear(cls):
super(Collection, cls).clear()
def _version_path(self, ver):
"""Returns path of file in versions repository"""
return os.path.join(self.path, str(ver))
class Version(object):
"""A single version in a collection
:param vernum: Version Number
:param path: Path to script files
:param filelist: List of scripts
:type vernum: int, VerNum
:type path: string
:type filelist: list
"""
def __init__(self, vernum, path, filelist):
self.version = VerNum(vernum)
# Collect scripts in this folder
self.sql = dict()
self.python = None
for script in filelist:
self.add_script(os.path.join(path, script))
def script(self, database=None, operation=None):
"""Returns SQL or Python Script"""
for db in (database, 'default'):
# Try to return a .sql script first
try:
return self.sql[db][operation]
except KeyError:
continue # No .sql script exists
# TODO: maybe add force Python parameter?
ret = self.python
assert ret is not None, \
"There is no script for %d version" % self.version
return ret
def add_script(self, path):
"""Add script to Collection/Version"""
if path.endswith(Extensions.py):
self._add_script_py(path)
elif path.endswith(Extensions.sql):
self._add_script_sql(path)
SQL_FILENAME = re.compile(r'^.*\.sql')
def _add_script_sql(self, path):
basename = os.path.basename(path)
match = self.SQL_FILENAME.match(basename)
if match:
basename = basename.replace('.sql', '')
parts = basename.split('_')
if len(parts) < 3:
raise exceptions.ScriptError(
"Invalid SQL script name %s " % basename + \
"(needs to be ###_description_database_operation.sql)")
version = parts[0]
op = parts[-1]
# NOTE(mriedem): check for ibm_db_sa as the database in the name
if 'ibm_db_sa' in basename:
if len(parts) == 6:
dbms = '_'.join(parts[-4: -1])
else:
raise exceptions.ScriptError(
"Invalid ibm_db_sa SQL script name '%s'; "
"(needs to be "
"###_description_ibm_db_sa_operation.sql)" % basename)
else:
dbms = parts[-2]
else:
raise exceptions.ScriptError(
"Invalid SQL script name %s " % basename + \
"(needs to be ###_description_database_operation.sql)")
# File the script into a dictionary
self.sql.setdefault(dbms, {})[op] = script.SqlScript(path)
def _add_script_py(self, path):
if self.python is not None:
raise exceptions.ScriptError('You can only have one Python script '
'per version, but you have: %s and %s' % (self.python, path))
self.python = script.PythonScript(path)
class Extensions(object):
"""A namespace for file extensions"""
py = 'py'
sql = 'sql'
def str_to_filename(s):
"""Replaces spaces, (double and single) quotes
and double underscores to underscores
"""
s = s.replace(' ', '_').replace('"', '_').replace("'", '_').replace(".", "_")
while '__' in s:
s = s.replace('__', '_')
return s