1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
|
#!/usr/bin/env python3
#
# Copyright (C) 2017 Codethink Limited
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library. If not, see <http://www.gnu.org/licenses/>.
#
# Authors:
# Tristan Van Berkom <tristan.vanberkom@codethink.co.uk>
#
import jinja2
from collections import Mapping
from .. import _yaml
from .._exceptions import LoadError, LoadErrorReason
from .optionbool import OptionBool
from .optionenum import OptionEnum
from .optionflags import OptionFlags
from .optioneltmask import OptionEltMask
from .optionarch import OptionArch
OPTION_TYPES = {
OptionBool.OPTION_TYPE: OptionBool,
OptionEnum.OPTION_TYPE: OptionEnum,
OptionFlags.OPTION_TYPE: OptionFlags,
OptionEltMask.OPTION_TYPE: OptionEltMask,
OptionArch.OPTION_TYPE: OptionArch,
}
class OptionPool():
def __init__(self, element_path):
self.options = {} # The Options
self.variables = None # The Options resolved into typed variables
# We hold on to the element path for the sake of OptionEltMask
self.element_path = element_path
# jinja2 environment, with default globals cleared out of the way
self.environment = jinja2.Environment(undefined=jinja2.StrictUndefined)
self.environment.globals = []
# load()
#
# Loads the options described in the project.conf
#
# Args:
# node (dict): The loaded YAML options
#
def load(self, options):
for option_name, option_definition in _yaml.node_items(options):
opt_type_name = _yaml.node_get(option_definition, str, 'type')
try:
opt_type = OPTION_TYPES[opt_type_name]
except KeyError:
p = _yaml.node_get_provenance(option_definition, 'type')
raise LoadError(LoadErrorReason.INVALID_DATA,
"{}: Invalid option type '{}'".format(p, opt_type_name))
option = opt_type(option_name, option_definition, self)
self.options[option_name] = option
# load_yaml_values()
#
# Loads the option values specified in a key/value
# dictionary loaded from YAML
#
# Args:
# node (dict): The loaded YAML options
#
def load_yaml_values(self, node):
for option_name, _ in _yaml.node_items(node):
try:
option = self.options[option_name]
except KeyError as e:
p = _yaml.node_get_provenance(node, option_name)
raise LoadError(LoadErrorReason.INVALID_DATA,
"{}: Unknown option '{}' specified".format(p, option_name))
option.load_value(node)
# load_cli_values()
#
# Loads the option values specified in a list of tuples
# collected from the command line
#
# Args:
# cli_options (list): A list of (str, str) tuples
#
def load_cli_values(self, cli_options):
for option_name, option_value in cli_options:
try:
option = self.options[option_name]
except KeyError as e:
raise LoadError(LoadErrorReason.INVALID_DATA,
"Unknown option '{}' specified on the command line".format(option_name))
option.set_value(option_value)
# resolve()
#
# Resolves the loaded options, this is just a step which must be
# performed after loading all options and their values, and before
# ever trying to evaluate an expression
#
def resolve(self):
self.variables = {}
for option_name, option in self.options.items():
# Delegate one more method for options to
# do some last minute validation once any
# overrides have been performed.
#
option.resolve()
self.variables[option_name] = option.value
# evaluate()
#
# Evaluates a jinja2 style expression with the loaded options in context.
#
# Args:
# expression (str): The jinja2 style expression
#
# Returns:
# (bool): Whether the expression resolved to a truthy value or a falsy one.
#
# Raises:
# LoadError: If the expression failed to resolve for any reason
#
def evaluate(self, expression):
#
# Variables must be resolved at this point.
#
try:
template_string = "{{% if {} %}} True {{% else %}} False {{% endif %}}".format(expression)
template = self.environment.from_string(template_string)
context = template.new_context(self.variables, shared=True)
result = template.root_render_func(context)
evaluated = jinja2.utils.concat(result)
val = evaluated.strip()
if val == "True":
return True
elif val == "False":
return False
else: # pragma: nocover
raise LoadError(LoadErrorReason.EXPRESSION_FAILED,
"Failed to evaluate expression: {}".format(expression))
except jinja2.exceptions.TemplateError as e:
raise LoadError(LoadErrorReason.EXPRESSION_FAILED,
"Failed to evaluate expression ({}): {}".format(expression, e))
# process_node()
#
# Args:
# node (Mapping): A YAML Loaded dictionary
#
def process_node(self, node):
# A conditional will result in composition, which can
# in turn add new conditionals to the root.
#
# Keep processing conditionals on the root node until
# all directly nested conditionals are resolved.
#
while self.process_one_node(node):
pass
# Now recurse into nested dictionaries and lists
# and process any indirectly nested conditionals.
#
for key, value in _yaml.node_items(node):
if isinstance(value, Mapping):
self.process_node(value)
elif isinstance(value, list):
self.process_list(value)
# Recursion assistent for lists, in case there
# are lists of lists.
#
def process_list(self, values):
for value in values:
if isinstance(value, Mapping):
self.process_node(value)
elif isinstance(value, list):
self.process_list(value)
# Process a single conditional, resulting in composition
# at the root level on the passed node
#
# Return true if a conditional was processed.
#
def process_one_node(self, node):
conditions = _yaml.node_get(node, list, '(?)', default_value=[]) or None
assertion = _yaml.node_get(node, str, '(!)', default_value='') or None
# Process assersions first, we want to abort on the first encountered
# assertion in a given dictionary, and not lose an assertion due to
# it being overwritten by a later assertion which might also trigger.
if assertion is not None:
p = _yaml.node_get_provenance(node, '(!)')
raise LoadError(LoadErrorReason.USER_ASSERTION,
"{}: {}".format(p, assertion.strip()))
if conditions is not None:
# Collect provenance first, we need to delete the (?) key
# before any composition occurs.
provenance = [
_yaml.node_get_provenance(node, '(?)', indices=[i])
for i in range(len(conditions))
]
del node['(?)']
for condition, p in zip(conditions, provenance):
tuples = list(_yaml.node_items(condition))
if len(tuples) > 1:
raise LoadError(LoadErrorReason.INVALID_DATA,
"{}: Conditional statement has more than one key".format(p))
expression, value = tuples[0]
try:
if self.evaluate(expression):
_yaml.composite(node, value)
except LoadError as e:
# Prepend the provenance of the error
raise LoadError(e.reason, "{}: {}".format(p, e)) from e
return True
return False
|
