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# Copyright (C) 2012 Canonical Ltd.
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# Copyright (C) 2012 Hewlett-Packard Development Company, L.P.
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# Copyright (C) 2012 Yahoo! Inc.
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# Copyright (C) 2016 Amazon.com, Inc. or its affiliates.
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# Author: Scott Moser <scott.moser@canonical.com>
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# Author: Juerg Haefliger <juerg.haefliger@hp.com>
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# Author: Joshua Harlow <harlowja@yahoo-inc.com>
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# Author: Andrew Jorgensen <ajorgens@amazon.com>
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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 version 3, as
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# published by the Free Software Foundation.
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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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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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from Cheetah.Template import Template as CTemplate
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CHEETAH_AVAILABLE = True
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except (ImportError, AttributeError):
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CHEETAH_AVAILABLE = False
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from jinja2 import Template as JTemplate
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JINJA_AVAILABLE = True
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except (ImportError, AttributeError):
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JINJA_AVAILABLE = False
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from cloudinit import log as logging
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from cloudinit import type_utils as tu
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from cloudinit import util
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LOG = logging.getLogger(__name__)
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TYPE_MATCHER = re.compile(r"##\s*template:(.*)", re.I)
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BASIC_MATCHER = re.compile(r'\$\{([A-Za-z0-9_.]+)\}|\$([A-Za-z0-9_.]+)')
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def basic_render(content, params):
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"""This does simple replacement of bash variable like templates.
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It identifies patterns like ${a} or $a and can also identify patterns like
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${a.b} or $a.b which will look for a key 'b' in the dictionary rooted
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# Only 1 of the 2 groups will actually have a valid entry.
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raise RuntimeError("Match encountered but no valid group present")
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path = collections.deque(name.split("."))
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selected_params = params
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if not isinstance(selected_params, dict):
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raise TypeError("Can not traverse into"
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" non-dictionary '%s' of type %s while"
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" looking for subkey '%s'"
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tu.obj_name(selected_params),
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selected_params = selected_params[key]
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if not isinstance(selected_params, dict):
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raise TypeError("Can not extract key '%s' from non-dictionary"
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% (key, selected_params,
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tu.obj_name(selected_params)))
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return str(selected_params[key])
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return BASIC_MATCHER.sub(replacer, content)
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def detect_template(text):
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def cheetah_render(content, params):
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return CTemplate(content, searchList=[params]).respond()
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def jinja_render(content, params):
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# keep_trailing_newline is in jinja2 2.7+, not 2.6
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add = "\n" if content.endswith("\n") else ""
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return JTemplate(content,
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undefined=jinja2.StrictUndefined,
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trim_blocks=True).render(**params) + add
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if text.find("\n") != -1:
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ident, rest = text.split("\n", 1)
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type_match = TYPE_MATCHER.match(ident)
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if CHEETAH_AVAILABLE:
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LOG.debug("Using Cheetah as the renderer for unknown template.")
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return ('cheetah', cheetah_render, text)
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return ('basic', basic_render, text)
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template_type = type_match.group(1).lower().strip()
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if template_type not in ('jinja', 'cheetah', 'basic'):
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raise ValueError("Unknown template rendering type '%s' requested"
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if template_type == 'jinja' and not JINJA_AVAILABLE:
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LOG.warn("Jinja not available as the selected renderer for"
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" desired template, reverting to the basic renderer.")
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return ('basic', basic_render, rest)
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elif template_type == 'jinja' and JINJA_AVAILABLE:
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return ('jinja', jinja_render, rest)
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if template_type == 'cheetah' and not CHEETAH_AVAILABLE:
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LOG.warn("Cheetah not available as the selected renderer for"
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" desired template, reverting to the basic renderer.")
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return ('basic', basic_render, rest)
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elif template_type == 'cheetah' and CHEETAH_AVAILABLE:
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return ('cheetah', cheetah_render, rest)
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# Only thing left over is the basic renderer (it is always available).
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return ('basic', basic_render, rest)
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def render_from_file(fn, params):
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template_type, renderer, content = detect_template(util.load_file(fn))
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LOG.debug("Rendering content of '%s' using renderer %s", fn, template_type)
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return renderer(content, params)
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def render_to_file(fn, outfn, params, mode=0o644):
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contents = render_from_file(fn, params)
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util.write_file(outfn, contents, mode=mode)
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def render_string_to_file(content, outfn, params, mode=0o644):
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contents = render_string(content, params)
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util.write_file(outfn, contents, mode=mode)
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def render_string(content, params):
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template_type, renderer, content = detect_template(content)
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return renderer(content, params)
added
removed
cloudinit/templater.py
