diff options
Diffstat (limited to 'cloudinit/templater.py')
| -rw-r--r-- | cloudinit/templater.py | 111 |
1 files changed, 69 insertions, 42 deletions
diff --git a/cloudinit/templater.py b/cloudinit/templater.py index a00ade20..1e147d4a 100644 --- a/cloudinit/templater.py +++ b/cloudinit/templater.py @@ -12,17 +12,19 @@ import collections import re - +import sys try: from Cheetah.Template import Template as CTemplate + CHEETAH_AVAILABLE = True except (ImportError, AttributeError): CHEETAH_AVAILABLE = False try: - from jinja2 import Template as JTemplate from jinja2 import DebugUndefined as JUndefined + from jinja2 import Template as JTemplate + JINJA_AVAILABLE = True except (ImportError, AttributeError): JINJA_AVAILABLE = False @@ -31,26 +33,28 @@ except (ImportError, AttributeError): from cloudinit import log as logging from cloudinit import type_utils as tu from cloudinit import util - +from cloudinit.atomic_helper import write_file LOG = logging.getLogger(__name__) TYPE_MATCHER = re.compile(r"##\s*template:(.*)", re.I) -BASIC_MATCHER = re.compile(r'\$\{([A-Za-z0-9_.]+)\}|\$([A-Za-z0-9_.]+)') -MISSING_JINJA_PREFIX = u'CI_MISSING_JINJA_VAR/' +BASIC_MATCHER = re.compile(r"\$\{([A-Za-z0-9_.]+)\}|\$([A-Za-z0-9_.]+)") +MISSING_JINJA_PREFIX = "CI_MISSING_JINJA_VAR/" class UndefinedJinjaVariable(JUndefined): """Class used to represent any undefined jinja template variable.""" def __str__(self): - return u'%s%s' % (MISSING_JINJA_PREFIX, self._undefined_name) + return "%s%s" % (MISSING_JINJA_PREFIX, self._undefined_name) def __sub__(self, other): - other = str(other).replace(MISSING_JINJA_PREFIX, '') + other = str(other).replace(MISSING_JINJA_PREFIX, "") raise TypeError( 'Undefined jinja variable: "{this}-{other}". Jinja tried' ' subtraction. Perhaps you meant "{this}_{other}"?'.format( - this=self._undefined_name, other=other)) + this=self._undefined_name, other=other + ) + ) def basic_render(content, params): @@ -73,67 +77,75 @@ def basic_render(content, params): while len(path) > 1: key = path.popleft() if not isinstance(selected_params, dict): - raise TypeError("Can not traverse into" - " non-dictionary '%s' of type %s while" - " looking for subkey '%s'" - % (selected_params, - tu.obj_name(selected_params), - key)) + raise TypeError( + "Can not traverse into" + " non-dictionary '%s' of type %s while" + " looking for subkey '%s'" + % (selected_params, tu.obj_name(selected_params), key) + ) selected_params = selected_params[key] key = path.popleft() if not isinstance(selected_params, dict): - raise TypeError("Can not extract key '%s' from non-dictionary" - " '%s' of type %s" - % (key, selected_params, - tu.obj_name(selected_params))) + raise TypeError( + "Can not extract key '%s' from non-dictionary '%s' of type %s" + % (key, selected_params, tu.obj_name(selected_params)) + ) return str(selected_params[key]) return BASIC_MATCHER.sub(replacer, content) def detect_template(text): - def cheetah_render(content, params): return CTemplate(content, searchList=[params]).respond() def jinja_render(content, params): # keep_trailing_newline is in jinja2 2.7+, not 2.6 add = "\n" if content.endswith("\n") else "" - return JTemplate(content, - undefined=UndefinedJinjaVariable, - trim_blocks=True).render(**params) + add + return ( + JTemplate( + content, undefined=UndefinedJinjaVariable, trim_blocks=True + ).render(**params) + + add + ) if text.find("\n") != -1: ident, rest = text.split("\n", 1) else: ident = text - rest = '' + rest = "" type_match = TYPE_MATCHER.match(ident) if not type_match: if CHEETAH_AVAILABLE: LOG.debug("Using Cheetah as the renderer for unknown template.") - return ('cheetah', cheetah_render, text) + return ("cheetah", cheetah_render, text) else: - return ('basic', basic_render, text) + return ("basic", basic_render, text) else: template_type = type_match.group(1).lower().strip() - if template_type not in ('jinja', 'cheetah', 'basic'): - raise ValueError("Unknown template rendering type '%s' requested" - % template_type) - if template_type == 'jinja' and not JINJA_AVAILABLE: - LOG.warning("Jinja not available as the selected renderer for" - " desired template, reverting to the basic renderer.") - return ('basic', basic_render, rest) - elif template_type == 'jinja' and JINJA_AVAILABLE: - return ('jinja', jinja_render, rest) - if template_type == 'cheetah' and not CHEETAH_AVAILABLE: - LOG.warning("Cheetah not available as the selected renderer for" - " desired template, reverting to the basic renderer.") - return ('basic', basic_render, rest) - elif template_type == 'cheetah' and CHEETAH_AVAILABLE: - return ('cheetah', cheetah_render, rest) + if template_type not in ("jinja", "cheetah", "basic"): + raise ValueError( + "Unknown template rendering type '%s' requested" + % template_type + ) + if template_type == "jinja" and not JINJA_AVAILABLE: + LOG.warning( + "Jinja not available as the selected renderer for" + " desired template, reverting to the basic renderer." + ) + return ("basic", basic_render, rest) + elif template_type == "jinja" and JINJA_AVAILABLE: + return ("jinja", jinja_render, rest) + if template_type == "cheetah" and not CHEETAH_AVAILABLE: + LOG.warning( + "Cheetah not available as the selected renderer for" + " desired template, reverting to the basic renderer." + ) + return ("basic", basic_render, rest) + elif template_type == "cheetah" and CHEETAH_AVAILABLE: + return ("cheetah", cheetah_render, rest) # Only thing left over is the basic renderer (it is always available). - return ('basic', basic_render, rest) + return ("basic", basic_render, rest) def render_from_file(fn, params): @@ -143,7 +155,8 @@ def render_from_file(fn, params): # If it is given a str that has non-ascii then it will raise a # UnicodeDecodeError. So we explicitly convert to unicode type here. template_type, renderer, content = detect_template( - util.load_file(fn, decode=False).decode('utf-8')) + util.load_file(fn, decode=False).decode("utf-8") + ) LOG.debug("Rendering content of '%s' using renderer %s", fn, template_type) return renderer(content, params) @@ -168,4 +181,18 @@ def render_string(content, params): _template_type, renderer, content = detect_template(content) return renderer(content, params) + +def render_cloudcfg(variant, template, output): + + with open(template, "r") as fh: + contents = fh.read() + tpl_params = {"variant": variant} + contents = (render_string(contents, tpl_params)).rstrip() + "\n" + util.load_yaml(contents) + if output == "-": + sys.stdout.write(contents) + else: + write_file(output, contents, omode="w") + + # vi: ts=4 expandtab |