jenkins-job-builder/jenkins_jobs/formatter.py

153 lines
5.2 KiB
Python

#!/usr/bin/env python
# Copyright (C) 2015 OpenStack, LLC.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
# Manage interpolation of JJB variables into template strings.
import logging
from pprint import pformat
import re
from string import Formatter
from jenkins_jobs.errors import JenkinsJobsException
from jenkins_jobs.local_yaml import CustomLoader
logger = logging.getLogger(__name__)
def deep_format(obj, paramdict, allow_empty=False):
"""Deep format configuration.
Apply the paramdict via str.format() to all string objects found within
the supplied obj. Lists and dicts are traversed recursively.
"""
# YAML serialisation was originally used to achieve this, but that places
# limitations on the values in paramdict - the post-format result must
# still be valid YAML (so substituting-in a string containing quotes, for
# example, is problematic).
if hasattr(obj, "format"):
try:
ret = CustomFormatter(allow_empty).format(obj, **paramdict)
except KeyError as exc:
missing_key = exc.args[0]
desc = "%s parameter missing to format %s\nGiven:\n%s" % (
missing_key,
obj,
pformat(paramdict),
)
raise JenkinsJobsException(desc)
except Exception:
logging.error(
"Problem formatting with args:\nallow_empty:"
"%s\nobj: %s\nparamdict: %s" % (allow_empty, obj, paramdict)
)
raise
elif isinstance(obj, list):
ret = type(obj)()
for item in obj:
ret.append(deep_format(item, paramdict, allow_empty))
elif isinstance(obj, dict):
ret = type(obj)()
for item in obj:
try:
ret[deep_format(item, paramdict, allow_empty)] = deep_format(
obj[item], paramdict, allow_empty
)
except KeyError as exc:
missing_key = exc.args[0]
desc = "%s parameter missing to format %s\nGiven:\n%s" % (
missing_key,
obj,
pformat(paramdict),
)
raise JenkinsJobsException(desc)
except Exception:
logging.error(
"Problem formatting with args:\nallow_empty:"
"%s\nobj: %s\nparamdict: %s" % (allow_empty, obj, paramdict)
)
raise
else:
ret = obj
if isinstance(ret, CustomLoader):
# If we have a CustomLoader here, we've lazily-loaded a template
# or rendered a template to a piece of YAML;
# attempt to format it.
ret = deep_format(
ret.get_object_to_format(), paramdict, allow_empty=allow_empty
)
return ret
class CustomFormatter(Formatter):
"""
Custom formatter to allow non-existing key references when formatting a
string
"""
_expr = r"""
(?<!{){({{)* # non-pair opening {
(?:obj:)? # obj:
(?P<key>\w+) # key
(?:\|(?P<default>[^}]*))? # default fallback
}(}})*(?!}) # non-pair closing }
"""
def __init__(self, allow_empty=False):
super(CustomFormatter, self).__init__()
self.allow_empty = allow_empty
def vformat(self, format_string, args, kwargs):
matcher = re.compile(self._expr, re.VERBOSE)
# special case of returning the object if the entire string
# matches a single parameter
try:
result = re.match("^%s$" % self._expr, format_string, re.VERBOSE)
except TypeError:
return format_string.format(**kwargs)
if result is not None:
try:
return kwargs[result.group("key")]
except KeyError:
pass
# handle multiple fields within string via a callback to re.sub()
def re_replace(match):
key = match.group("key")
default = match.group("default")
if default is not None:
if key not in kwargs:
return default
else:
return "{%s}" % key
return match.group(0)
format_string = matcher.sub(re_replace, format_string)
return Formatter.vformat(self, format_string, args, kwargs)
def get_value(self, key, args, kwargs):
try:
return Formatter.get_value(self, key, args, kwargs)
except KeyError:
if self.allow_empty:
logger.debug(
"Found uninitialized key %s, replaced with empty string", key
)
return ""
raise