jenkins-job-builder/jenkins_jobs/formatter.py

135 lines
4.5 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 _string
import logging
import re
from string import Formatter
from jinja2 import Undefined
from jinja2.exceptions import UndefinedError
from .errors import JenkinsJobsException
logger = logging.getLogger(__name__)
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 }
"""
_matcher = re.compile(_expr, re.VERBOSE)
_whole_matcher = re.compile(f"^{_expr}$", re.VERBOSE)
def __init__(self, allow_empty=False):
super().__init__()
self.allow_empty = allow_empty
def vformat(self, format_string, args, kwargs):
# Special case of returning the object preserving it's type if the entire string
# matches a single parameter.
result = self._whole_matcher.match(format_string)
if result is not None:
try:
value = kwargs[result.group("key")]
except KeyError:
pass
else:
if not isinstance(value, Undefined):
return value
# 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 or isinstance(kwargs[key], Undefined):
return default
else:
return "{%s}" % key
return match.group(0)
format_string = self._matcher.sub(re_replace, format_string)
try:
return super().vformat(format_string, args, kwargs)
except (JenkinsJobsException, UndefinedError, ValueError) as x:
if len(format_string) > 40:
short_fmt = format_string[:80] + "..."
else:
short_fmt = format_string
raise JenkinsJobsException(f"While formatting string {short_fmt!r}: {x}")
def enum_required_params(self, format_string):
def re_replace(match):
key = match.group("key")
return "{%s}" % key
prepared_format_string = self._matcher.sub(re_replace, format_string)
for literal_text, field_name, format_spec, conversion in self.parse(
prepared_format_string
):
if field_name is None:
continue
arg_used, rest = _string.formatter_field_name_split(field_name)
if arg_used == "" or type(arg_used) is int:
raise JenkinsJobsException(
f"Positional format arguments are not supported: {format_string!r}"
)
yield arg_used
def enum_param_defaults(self, format_string):
for match in self._matcher.finditer(format_string):
key = match.group("key")
default = match.group("default")
if default is not None:
yield (key, default)
def get_value(self, key, args, kwargs):
try:
return super().get_value(key, args, kwargs)
except KeyError:
if self.allow_empty:
logger.debug(
"Found uninitialized key %s, replaced with empty string", key
)
return ""
raise JenkinsJobsException(f"Missing parameter: {key!r}")
def enum_str_format_required_params(format, pos):
formatter = CustomFormatter()
try:
yield from formatter.enum_required_params(str(format))
except JenkinsJobsException as x:
raise x.with_pos(pos)
def enum_str_format_param_defaults(format):
formatter = CustomFormatter()
yield from formatter.enum_param_defaults(str(format))