avoid-omap-ruamel.py

# ruamel.yaml adds !!omap when using ordered dicts
# and there is no switch to avoid such  behaviour
# Here is a workarond to put all keys in specific order
# and instead of following constuctions:
# list:
#   - !!omap
#     - [key1, value1]
#     - [key2, value2]
# create this one:
# list:
#   - key1: value1
#     key2: value2
#
# Issue: https://bitbucket.org/ruamel/yaml/issues/226/unable-to-generate-yaml-without-omap-with

import sys
from ruamel.yaml.comments import CommentedMap as OrderedDict  # to avoid '!!omap' in yaml

import ruamel.yaml

yaml = ruamel.yaml.YAML()  # defaults to round-trip
yaml.version = '1.1'

data = [
    OrderedDict([
        ('hosts', 'all'), 
        ('vars', {'some_var': True}),
        ('tasks', [
            OrderedDict([('name', 'print some_var'), ('debug', {'var': 'some_var'})])
        ]),
    ])
]

yaml.dump(data, sys.stdout)