Jinja2 sort filter and Python 3

[Sergey Baranov]

Hi everyone!

I'm using this jinja2 macro for xml configs:

{%- macro print_opts(options, indent='  ', count=0) %}

{% for key in options.keys() | sort2 %}

  {% set value = options[key] %}

  {% if value is string %}

    {{- indent*count }}{{ key }} {{ '"' + value.split('\t') | join('" "') + '"' }}

  {% elif value in [true, false] %}

    {{- indent*count }}{{ key }} {{ value | lower }}

  {% elif value is number %}

    {{- indent*count }}{{ key }} {{ value }}

  {% elif value is mapping %}

    {{- indent*count }}<{{ key }}>

     {{ print_opts(value, indent, count+1) -}}

    {{- indent*count }}</{{ key.split()[0] }}>

  {% elif value is sequence %}

    {% for i in value | sort2 -%}

      {{ print_opts({key: i}, indent, count) -}}

    {%- endfor %}

  {% else %}

    {{- indent*count }}{{ key }} "{{ value }}"

  {% endif %}

{% endfor %}

{% endmacro %}

This macro works fine with Python 2, but I need Python 3 support also. The problem is sort filter.

First, I've had the problem with dict sorting in Py3 (unorderable types: dict() < dict()) and created this custom sort filter:

from jinja2._compat import string_types

from operator import itemgetter

def environmentfilter(f):

    """Decorator for marking environment dependent filters.  The current

    :class:`Environment` is passed to the filter as first argument.

    """

    f.environmentfilter = True

    return f

@environmentfilter

def do_sort(environment, value, reverse=False, case_sensitive=False,

           attribute=None):

    if not case_sensitive:

        def sort_func(item):

            if isinstance(item, string_types):

                item = item.lower()

            return item

    else:

        sort_func = None

    if attribute is not None:

        getter = make_attrgetter(environment, attribute)

        def sort_func(item, processor=sort_func or (lambda x: x)):

            return processor(getter(item))

    print(type(value))

    if isinstance(value, list) and isinstance(value[0], dict):

        return sorted(value, key=lambda x:sorted(x.keys()), reverse=reverse)

    else:

        return sorted(value, key=sort_func, reverse=reverse)

class FilterModule(object):

    '''

    custom jinja2 sort filter

    '''

    def filters(self):

        return {

            'sort2': do_sort

        }

Here I am using different sorted key for list of dicts. But then I catch the next problem - list sorting.

With Python 2  print(type(value)) returns <type 'list'> and sorting works as expected

With Python 3 it returns <class 'dict_keys'> and I am getting different sorting per each ansible role running, config file always has changed state.

Please help me resolve this problem. Maybe someone knows a simpler solution to make this macro work on both Python versions.

Thanks