borgmatic/borgmatic/config/generate.py

91 lines
3.0 KiB
Python

from collections import OrderedDict
from ruamel import yaml
INDENT = 4
def write_configuration(config_filename, config):
'''
Given a target config filename and a config data structure of nested OrderedDicts, write out the
config to file as YAML.
'''
with open(config_filename, 'w') as config_file:
config_file.write(yaml.round_trip_dump(config, indent=INDENT, block_seq_indent=INDENT))
def _insert_newline_before_comment(config, field_name):
'''
Using some ruamel.yaml black magic, insert a blank line in the config right befor the given
field and its comments.
'''
config.ca.items[field_name][1].insert(
0,
yaml.tokens.CommentToken('\n', yaml.error.CommentMark(0), None),
)
def add_comments_to_configuration(config, schema, indent=0):
'''
Using descriptions from a schema as a source, add those descriptions as comments to the given
config before each field. This function only adds comments for the top-most config map level.
Indent the comment the given number of characters.
'''
for index, field_name in enumerate(config.keys()):
field_schema = schema['map'].get(field_name, {})
description = field_schema.get('desc')
# No description to use? Skip it.
if not schema or not description:
continue
config.yaml_set_comment_before_after_key(
key=field_name,
before=description,
indent=indent,
)
if index > 0:
_insert_newline_before_comment(config, field_name)
def _section_schema_to_sample_configuration(section_schema):
'''
Given the schema for a particular config section, generate and return sample config for that
section. Include comments for each field based on the schema "desc" description.
'''
section_config = yaml.comments.CommentedMap([
(field_name, field_schema['example'])
for field_name, field_schema in section_schema['map'].items()
])
add_comments_to_configuration(section_config, section_schema, indent=INDENT)
return section_config
def _schema_to_sample_configuration(schema):
'''
Given a loaded configuration schema, generate and return sample config for it. Include comments
for each section based on the schema "desc" description.
'''
config = yaml.comments.CommentedMap([
(section_name, _section_schema_to_sample_configuration(section_schema))
for section_name, section_schema in schema['map'].items()
])
add_comments_to_configuration(config, schema)
return config
def generate_sample_configuration(config_filename, schema_filename):
'''
Given a target config filename and the path to a schema filename in pykwalify YAML schema
format, write out a sample configuration file based on that schema.
'''
schema = yaml.round_trip_load(open(schema_filename))
config = _schema_to_sample_configuration(schema)
write_configuration(config_filename, config)