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
|
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (c) 2017 Cisco and/or its affiliates.
#
# 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.
#
import enum
from netmodel.model.mapper import ObjectSpecification
from vicn.core.exception import VICNException
#------------------------------------------------------------------------------
# Enums
#------------------------------------------------------------------------------
class RequirementScope(enum.Enum):
INSTANCE = 'Instance'
CLASS = 'Class'
#------------------------------------------------------------------------------
# Exceptions
#------------------------------------------------------------------------------
class RequirementError(VICNException):
def __init__(self, instance, attr):
super().__init__()
self._instance = instance
self._attr = attr
def __str__(self):
return "Requirement on {}.{} could not be satisfied:".format(
self._instance, self._attr)
class RequiredAttributeError(RequirementError):
def __str__(self):
return super().__str__() + "could not find attribute {}".format(
self._attr)
class RequiredPropertyError(RequirementError):
def __init__(self, instance, attr, prop):
super().__init__(instance, attr)
self._prop = prop
def __str__(self):
return super().__str__()+ "property {} is not verified".format(
self._prop)
#------------------------------------------------------------------------------
# Class: Property
#------------------------------------------------------------------------------
class Property:
TYPE_ANY_OF = 0
#XXX cant think of a good use case for that
#TYPE_ALL_OF = 1
def __init__(self, value, property_type=TYPE_ANY_OF):
self._type = property_type
try:
self._value = set(value)
except TypeError: #value is not iterable, it is a single value
self._value = set()
self._value.add(value)
@property
def property_type(self):
return self._type
@property
def value(self):
return self._value
def check(self, value):
return value in self._value
def __str__(self):
return str(self._value)
def merge(self, other):
assert self._type is other.property_type, \
"Properties must be of same type to be merged"
#if self._type is TYPE_ANY_OF:
self._value.intersection_update(other.value)
#elif self._type is TYPE_ALL_OF:
# self._value.union_update(other.value)
#------------------------------------------------------------------------------
# Class: Requirement
#------------------------------------------------------------------------------
class Requirement(ObjectSpecification):
"""Resource requirement
This class allows to specify a requirement on a given resource, or on a
class of resources (all instances of a given class).
"""
#--------------------------------------------------------------------------
# Constructor
#--------------------------------------------------------------------------
def __init__(self, requirement_type, properties = None,
capabilities = None, scope = RequirementScope.INSTANCE,
fatal = True, must_be_setup = False):
"""
Args:
requirement_type (): the attribute on which the requirement is made
properties (Optional[XXX]): XXX (defaults to None)
scope (Optional[enum RequirementScope]): Is the requirement dealing
with an instance, or a class (all instance of the class)
(defaults to RequirementScope.INSTANCE)
fatal (Optional[bool]): is the failure of the requirement fatal
(raises an error), or not (raises a warning) (defaults to True)
must_be_setup (Optional[bool]): defaults to False
"""
self._type = requirement_type
self._properties = {}
if properties:
for prop in properties:
self._properties[prop] = Property(properties[prop])
self._capabilities = capabilities if capabilities else set()
self._scope = scope
self._fatal = fatal
self._must_be_up = must_be_setup
#--------------------------------------------------------------------------
# Accessors and properties
#--------------------------------------------------------------------------
@property
def properties(self):
return self._properties
@property
def requirement_type(self):
return self._type
@property
def must_be_up(self):
return self._must_be_up
#--------------------------------------------------------------------------
# Display
#--------------------------------------------------------------------------
def __str__(self):
prop_str = "{" + ",".join(map(lambda x: "'{}': {}".format(x,
self._properties[x]), self._properties.keys())) +"}"
return "<type={}, properties={}, must_be_up={}>".format(self._type,
prop_str, self._must_be_up)
#--------------------------------------------------------------------------
# Requirement operators
#--------------------------------------------------------------------------
def check(self, instance):
if not hasattr(instance, self._type):
raise RequiredAttributeError(instance, self._type)
instance_attr = getattr(instance, self._type)
if not instance_attr:
raise TypeError("instance_attr is none")
for prop in self.properties:
if not hasattr(instance_attr, prop):
raise RequiredAttributeError(instance, self._type)
if not self._properties[prop].check(getattr(instance_attr, prop)):
raise RequiredPropertyError(instance, self._type, prop)
return True
#--------------------------------------------------------------------------
# Requirement logic
#--------------------------------------------------------------------------
def merge(self, other):
assert other.requirement_type == self._type, \
"Cannot merge Requirements with different types"
for prop in other.properties:
if prop in self._properties:
self._properties[prop].merge(other.properties[prop])
else:
self._properties[prop] = other.properties[prop]
if other._capabilities:
self._capabilities |= other._capabilities
#------------------------------------------------------------------------------
# Class: Requirement list
#------------------------------------------------------------------------------
class RequirementList(list):
def __init__(self,x=None):
super().__init__()
if x:
self.extend(x)
def append(self,x):
assert isinstance(x,Requirement)
# XXX O(n) right now, might be able to do better
for req in self:
if req.requirement_type == x.requirement_type:
req.merge(x)
return
super().append(x)
def extend(self, x):
for y in x:
self.append(y)
|
