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2550.2.2
by Robert Collins
Add helpers to get api versions from objects. |
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# Copyright (C) 2007 Canonical Ltd
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#
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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2550.2.3
by Robert Collins
Add require_api API. |
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"""Library API versioning support.
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Added in bzrlib 0.18 this allows export of compatibility information about
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bzrlib. Please see doc/developers/api-versioning.txt for design details and
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examples.
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"""
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2550.2.2
by Robert Collins
Add helpers to get api versions from objects. |
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import bzrlib |
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from bzrlib.lazy_import import lazy_import |
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lazy_import(globals(), """ |
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from bzrlib.errors import IncompatibleAPI
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""") |
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def get_current_api_version(object_with_api): |
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"""Return the API version tuple for object_with_api.
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:param object_with_api: An object to look for an API version on. If the
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object has a api_current_version attribute, that is used. Otherwise if
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there is a version_info attribute, its first three elements are used.
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Finally if there was no version_info attribute, the current api version
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of bzrlib itself is used.
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2550.2.3
by Robert Collins
Add require_api API. |
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Added in bzrlib 0.18.
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2550.2.2
by Robert Collins
Add helpers to get api versions from objects. |
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"""
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try: |
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return object_with_api.api_current_version |
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except AttributeError: |
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try: |
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return object_with_api.version_info[0:3] |
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except AttributeError: |
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return get_current_api_version(bzrlib) |
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def get_minimum_api_version(object_with_api): |
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"""Return the minimum API version supported by object_with_api.
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:param object_with_api: An object to look for an API version on. If the
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object has a api_minimum_version attribute, that is used. Otherwise the
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minimum api version of bzrlib itself is used.
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2550.2.3
by Robert Collins
Add require_api API. |
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Added in bzrlib 0.18.
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2550.2.2
by Robert Collins
Add helpers to get api versions from objects. |
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"""
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try: |
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return object_with_api.api_minimum_version |
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except AttributeError: |
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return get_minimum_api_version(bzrlib) |
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2550.2.3
by Robert Collins
Add require_api API. |
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def require_api(object_with_api, wanted_api): |
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"""Check if object_with_api supports the api version wanted_api.
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:param object_with_api: An object which exports an API minimum and current
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version. See get_minimum_api_version and get_current_api_version for
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details.
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:param wanted_api: The API version for which support is required.
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:return None:
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:raises IncompatibleAPI: When the wanted_api is not supported by
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object_with_api.
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Added in bzrlib 0.18.
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"""
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current = get_current_api_version(object_with_api) |
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minimum = get_minimum_api_version(object_with_api) |
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if wanted_api < minimum or wanted_api > current: |
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raise IncompatibleAPI(object_with_api, wanted_api, minimum, current) |