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
|
#!/usr/bin/env python
###############################################################################
# Copyright (c) 2016 Ericsson AB and others.
# peter.barabas@ericsson.com
# All rights reserved. This program and the accompanying materials
# are made available under the terms of the Apache License, Version 2.0
# which accompanies this distribution, and is available at
# http://www.apache.org/licenses/LICENSE-2.0
###############################################################################
import io
import re
import yaml
from common import(
err,
ArgParser,
)
TAG_START = '%{'
TAG_END = '}'
DELIMITER = '/'
class Templater(object):
def __init__(self, base_file, template_file, output_file):
self.template_file = template_file
self.output_file = output_file
self.base = self.load_yaml(base_file)
def load_yaml(self, filename):
try:
with io.open(filename) as yaml_file:
return yaml.load(yaml_file)
except Exception as error:
err('Error opening YAML file: %s' % error)
def save_yaml(self, filename, content):
try:
with io.open(filename, 'w') as yaml_file:
yaml_file.write(content)
except Exception as error:
err('Error writing YAML file: %s' % error)
def get_indent(self, line):
return len(line) - len(line.lstrip(' '))
def format_fragment(self, fragment, indent):
result = ''
is_first_line = True
for line in fragment.splitlines():
# Skip indenting the first line as it is already indented
if is_first_line:
line += '\n'
is_first_line = False
else:
line = ' ' * indent + line + '\n'
result += line
return result.rstrip('\n')
def format_substitution(self, string):
if isinstance(string, basestring):
return string
else:
return yaml.dump(string, default_flow_style=False)
def parse_interface_tag(self, tag):
# Remove 'interface(' prefix, trailing ')' and split arguments
args = tag[len('interface('):].rstrip(')').split(',')
if len(args) == 1 and not args[0]:
err('No arguments for interface().')
elif len(args) == 2 and (not args[0] or not args[1]):
err('Empty argument for interface().')
elif len(args) > 2:
err('Too many arguments for interface().')
else:
return args
def get_interface_from_network(self, interfaces, network):
nics = self.base[interfaces]
for nic in nics:
if network in nics[nic]:
return nic
err('Network not found: %s' % network)
def get_role_interfaces(self, role):
nodes = self.base['nodes']
for node in nodes:
if role in node['role']:
return node['interfaces']
err('Role not found: %s' % role)
def lookup_interface(self, args):
nodes = self.base['nodes']
if len(args) == 1:
interfaces = nodes[0]['interfaces']
if len(args) == 2:
interfaces = self.get_role_interfaces(args[1])
return self.get_interface_from_network(interfaces, args[0])
def parse_include_tag(self, tag):
# Remove 'include(' prefix and trailing ')'
filename = tag[len('include('):].rstrip(')')
if not filename:
err('No argument for include().')
return filename
def include_file(self, filename):
fragment = self.load_yaml(filename)
return yaml.dump(fragment, default_flow_style=False)
def parse_tag(self, tag, indent):
fragment = ''
if 'interface(' in tag:
args = self.parse_interface_tag(tag)
fragment = self.lookup_interface(args)
elif 'include(' in tag:
filename = self.parse_include_tag(tag)
fragment = self.include_file(filename)
else:
path = tag.split(DELIMITER)
fragment = self.base
for i in path:
if i in fragment:
fragment = fragment.get(i)
else:
err('Error: key "%s" does not exist in base YAML file' % i)
fragment = self.format_substitution(fragment)
return self.format_fragment(fragment, indent)
def run(self):
result = ''
regex = re.compile(re.escape(TAG_START) + r'([a-z].+)' + re.escape(TAG_END),
flags=re.IGNORECASE)
with io.open(self.template_file) as f:
for line in f:
indent = self.get_indent(line)
result += re.sub(regex,
lambda match: self.parse_tag(match.group(1), indent),
line)
self.save_yaml(self.output_file, result)
def parse_arguments():
description = '''Process 'template_file' using 'base_file' as source for
template variable substitution and write the results to 'output_file'.'''
parser = ArgParser(prog='python %s' % __file__,
description=description)
parser.add_argument('base_file',
help='Base YAML filename')
parser.add_argument('template_file',
help='Fragment filename')
parser.add_argument('output_file',
help='Output filename')
args = parser.parse_args()
return(args.base_file, args.template_file, args.output_file)
def main():
base_file, template_file, output_file = parse_arguments()
templater = Templater(base_file, template_file, output_file)
templater.run()
if __name__ == '__main__':
main()
|
