SaltStack: Custom state and execution module for ansible-like 'assemble' function

_modules\ssx.py

import os
import salt.loader
import salt.utils
import salt.utils.jinja
import salt.utils.files

from salt.exceptions import SaltInvocationError, CommandExecutionError


def get_assemble_fragments(fragments_path, include_pattern=None, exclude_pattern=None):
    # Verify given fragments path
    if not os.path.isabs(fragments_path):
        raise SaltInvocationError('Fragments path must be absolute: {0}'.format(fragments_path))
    if not os.path.isdir(fragments_path):
        raise SaltInvocationError('Fragments path must exist and be a directory: {0}'.format(fragments_path))

    # Get list of all fragment files
    fragment_file_paths = set()
    try:
        # List all directory entries without using recursion
        for entry_name in os.listdir(fragments_path):
            entry_path = os.path.join(fragments_path, entry_name)

            # Skip entry if path is not a file
            if not os.path.isfile(entry_path):
                continue

            # Skip entry if name does not match include/exclude_pat
            if not salt.utils.check_include_exclude(entry_path, include_pattern, exclude_pattern):
                continue

            # Append entry to set of source files
            fragment_file_paths.add(entry_path)
    except Exception as exc:
        raise CommandExecutionError('Could not build list of fragment files: {0}'.format(exc))

    # Collect content of all fragment files, sorted by name/path
    fragments = []
    try:
        for fragment_file_path in sorted(fragment_file_paths):
            with open(fragment_file_path, 'r') as fragment_file:
                fragments.append({'source': fragment_file_path, 'content': fragment_file.read()})
    except Exception as exc:
        raise CommandExecutionError('Unable to collect content of fragment files: {0}'.format(exc))

    # Return collected fragments
    return fragments

_states\ssx.py

# noinspection PyUnresolvedReferences
from salt.states.file import *


def _error(ret, err_msg):
    ret['result'] = False
    ret['comment'] = err_msg
    return ret


def assemble(name,
             fragments,
             include_pat=None,
             exclude_pat=None,
             template_src=None,
             **kwargs):
    ret = {
        'name': name,
        'changes': {},
        'pchanges': {},
        'result': True,
        'comment': ''
    }

    # Fetch all fragments by executing ssx.get_assemble_fragments
    try:
        fragments = __salt__['ssx.get_assemble_fragments'](fragments_path=fragments, include_pattern=include_pat,
                                                           exclude_pattern=exclude_pat)
    except Exception as exc:
        return _error(ret, exc)

    # Remove specific, dangerous keys before passing all kwargs to file.managed
    for key in ('source', 'source_hash', 'contents', 'contents_grains', 'contents_pillar'):
        kwargs.pop(key, None)

    # Override kwargs for contents/source for fragments rendering
    if not template_src:
        fragment_contents = ([fragment['content'] for fragment in fragments])
        kwargs.update({
            'name': name,
            'contents': fragment_contents
        })
    else:
        context = kwargs.get('context', {})
        context.update({'__fragments__': fragments})
        kwargs.update({
            'name': name,
            'source': template_src,
            'context': context
        })

    # Execute file.managed state with modified kwargs, merge the results and return
    ret.update(__states__['file.managed'](**kwargs))
    return ret

assemble.j2

THIS IS HEADA!
{%- for fragment in __fragments__ %}
# {{ fragment.source }} {{ '{{{' }}
{{ fragment.content -}}
# {{ '}}}' }}
{%- endfor %}
THIS IS FOOTA!

assemble.sls

/tmp/development/salt/assemble1.cfg:
  ssx.assemble:
    - fragments: /tmp/development/salt/assemble1-fragments
    
/tmp/development/salt/assemble2.cfg:
  ssx.assemble:
    - fragments: /tmp/development/salt/assemble2-fragments
    - include_pat: '*.conf'
    - template: jinja
    - template_src: salt://assemble.j2
    - check_cmd: /bin/true