okd/roles/lib_yaml_editor/library/yedit.py

#!/usr/bin/env python
#     ___ ___ _  _ ___ ___    _ _____ ___ ___
#    / __| __| \| | __| _ \  /_\_   _| __|   \
#   | (_ | _|| .` | _||   / / _ \| | | _|| |) |
#    \___|___|_|\_|___|_|_\/_/_\_\_|_|___|___/_ _____
#   |   \ / _ \  | \| |/ _ \_   _| | __|   \_ _|_   _|
#   | |) | (_) | | .` | (_) || |   | _|| |) | |  | |
#   |___/ \___/  |_|\_|\___/ |_|   |___|___/___| |_|

'''
module for managing yaml files
'''

import os
import re

import yaml
# This is here because of a bug that causes yaml
# to incorrectly handle timezone info on timestamps
def timestamp_constructor(_, node):
    ''' return timestamps as strings'''
    return str(node.value)
yaml.add_constructor(u'tag:yaml.org,2002:timestamp', timestamp_constructor)


class YeditException(Exception):
    ''' Exception class for Yedit '''
    pass

class Yedit(object):
    ''' Class to modify yaml files '''
    re_valid_key = r"(((\[-?\d+\])|(\w+)).?)+$"
    re_key = r"(?:\[(-?\d+)\])|(\w+)"

    def __init__(self, filename=None, content=None, content_type='yaml'):
        self.content = content
        self.filename = filename
        self.__yaml_dict = content
        self.content_type = content_type
        if self.filename and not self.content:
            self.load(content_type=self.content_type)

    @property
    def yaml_dict(self):
        ''' getter method for yaml_dict '''
        return self.__yaml_dict

    @yaml_dict.setter
    def yaml_dict(self, value):
        ''' setter method for yaml_dict '''
        self.__yaml_dict = value

    @staticmethod
    def remove_entry(data, key):
        ''' remove data at location key '''
        if not (key and re.match(Yedit.re_valid_key, key) and isinstance(data, (list, dict))):
            return None

        key_indexes = re.findall(Yedit.re_key, key)
        for arr_ind, dict_key in key_indexes[:-1]:
            if dict_key and isinstance(data, dict):
                data = data.get(dict_key, None)
            elif arr_ind and isinstance(data, list) and int(arr_ind) <= len(data) - 1:
                data = data[int(arr_ind)]
            else:
                return None

        # process last index for remove
        # expected list entry
        if key_indexes[-1][0]:
            if isinstance(data, list) and int(key_indexes[-1][0]) <= len(data) - 1:
                del data[int(key_indexes[-1][0])]

        # expected dict entry
        elif key_indexes[-1][1]:
            if isinstance(data, dict):
                del data[key_indexes[-1][1]]

    @staticmethod
    def add_entry(data, key, item=None):
        ''' Get an item from a dictionary with key notation a.b.c
            d = {'a': {'b': 'c'}}}
            key = a.b
            return c
        '''
        if not (key and re.match(Yedit.re_valid_key, key) and isinstance(data, (list, dict))):
            return None

        curr_data = data

        key_indexes = re.findall(Yedit.re_key, key)
        for arr_ind, dict_key in key_indexes[:-1]:
            if dict_key:
                if isinstance(data, dict) and data.has_key(dict_key):
                    data = data[dict_key]
                    continue

                data[dict_key] = {}
                data = data[dict_key]

            elif arr_ind and isinstance(data, list) and int(arr_ind) <= len(data) - 1:
                data = data[int(arr_ind)]
            else:
                return None

        # process last index for add
        # expected list entry
        if key_indexes[-1][0] and isinstance(data, list) and int(key_indexes[-1][0]) <= len(data) - 1:
            data[int(key_indexes[-1][0])] = item

        # expected dict entry
        elif key_indexes[-1][1] and isinstance(data, dict):
            data[key_indexes[-1][1]] = item

        return curr_data

    @staticmethod
    def get_entry(data, key):
        ''' Get an item from a dictionary with key notation a.b.c
            d = {'a': {'b': 'c'}}}
            key = a.b
            return c
        '''
        if not (key and re.match(Yedit.re_valid_key, key) and isinstance(data, (list, dict))):
            return None

        key_indexes = re.findall(Yedit.re_key, key)
        for arr_ind, dict_key in key_indexes:
            if dict_key and isinstance(data, dict):
                data = data.get(dict_key, None)
            elif arr_ind and isinstance(data, list) and int(arr_ind) <= len(data) - 1:
                data = data[int(arr_ind)]
            else:
                return None

        return data

    def write(self):
        ''' write to file '''
        if not self.filename:
            raise YeditException('Please specify a filename.')

        with open(self.filename, 'w') as yfd:
            yfd.write(yaml.safe_dump(self.yaml_dict, default_flow_style=False))

    def read(self):
        ''' write to file '''
        # check if it exists
        if not self.exists():
            return None

        contents = None
        with open(self.filename) as yfd:
            contents = yfd.read()

        return contents

    def exists(self):
        ''' return whether file exists '''
        if os.path.exists(self.filename):
            return True

        return False

    def load(self, content_type='yaml'):
        ''' return yaml file '''
        contents = self.read()

        if not contents:
            return None

        # check if it is yaml
        try:
            if content_type == 'yaml':
                self.yaml_dict = yaml.load(contents)
            elif content_type == 'json':
                self.yaml_dict = json.loads(contents)
        except yaml.YAMLError as _:
            # Error loading yaml or json
            return None

        return self.yaml_dict

    def get(self, key):
        ''' get a specified key'''
        try:
            entry = Yedit.get_entry(self.yaml_dict, key)
        except KeyError as _:
            entry = None

        return entry

    def delete(self, key):
        ''' put key, value into a yaml file '''
        try:
            entry = Yedit.get_entry(self.yaml_dict, key)
        except KeyError as _:
            entry = None
        if not entry:
            return  (False, self.yaml_dict)

        Yedit.remove_entry(self.yaml_dict, key)
        return (True, self.yaml_dict)

    def put(self, key, value):
        ''' put key, value into a yaml file '''
        try:
            entry = Yedit.get_entry(self.yaml_dict, key)
        except KeyError as _:
            entry = None

        if entry == value:
            return (False, self.yaml_dict)

        Yedit.add_entry(self.yaml_dict, key, value)
        return (True, self.yaml_dict)

    def create(self, key, value):
        ''' create the file '''
        if not self.exists():
            self.yaml_dict = {key: value}
            return (True, self.yaml_dict)

        return (False, self.yaml_dict)

def main():
    '''
    ansible oc module for secrets
    '''

    module = AnsibleModule(
        argument_spec=dict(
            state=dict(default='present', type='str',
                       choices=['present', 'absent', 'list']),
            debug=dict(default=False, type='bool'),
            src=dict(default=None, type='str'),
            content=dict(default=None, type='dict'),
            key=dict(default=None, type='str'),
            value=dict(default=None, type='str'),
            value_format=dict(default='yaml', choices=['yaml', 'json'], type='str'),
        ),
        #mutually_exclusive=[["src", "content"]],

        supports_check_mode=True,
    )
    state = module.params['state']

    yamlfile = Yedit(module.params['src'], module.params['content'])

    rval = yamlfile.load()
    if not rval and state != 'present':
        module.fail_json(msg='Error opening file [%s].  Verify that the' + \
                             ' file exists, that it is has correct permissions, and is valid yaml.')

    if state == 'list':
        module.exit_json(changed=False, results=rval, state="list")

    if state == 'absent':
        rval = yamlfile.delete(module.params['key'])
        module.exit_json(changed=rval[0], results=rval[1], state="absent")

    if state == 'present':

        if module.params['value_format'] == 'yaml':
            value = yaml.load(module.params['value'])
        elif module.params['value_format'] == 'json':
            value = json.loads(module.params['value'])

        if rval:
            rval = yamlfile.put(module.params['key'], value)
            module.exit_json(changed=rval[0], results=rval[1], state="present")

        if not module.params['content']:
            rval = yamlfile.create(module.params['key'], value)
        else:
            yamlfile.write()
            rval = yamlfile.load()
        module.exit_json(changed=rval[0], results=rval[1], state="present")

    module.exit_json(failed=True,
                     changed=False,
                     results='Unknown state passed. %s' % state,
                     state="unknown")

# pylint: disable=redefined-builtin, unused-wildcard-import, wildcard-import, locally-disabled
# import module snippets.  This are required
from ansible.module_utils.basic import *

main()