Parse YAML inventory files with ansible-inventory

[gdevenyi]

Based on the stalled fboender/ansible-cmdb#204 by arnisoph (refs fboender#154), reworked to fix a control-flow bug in the original.

The bug

YAML is Ansible's inventory format of choice these days, but a .yml/.yaml inventory was handed to the ini parser. It doesn't fail — it silently invents hosts out of the YAML structure.

Given an ordinary YAML inventory, the parsed host list was:

'all'  'children'  'comment'  'dev'  'dtap'  'hosts'  'prod'  'vars'
'debian.dev.local'  'eek.electricmonk.nl'  'jib.electricmonk.nl'  ...

Eight fabricated hosts from YAML keywords, with host variables attached to the wrong entries. After this change:

debian.dev.local    -> {'dtap': 'dev'}
jib.electricmonk.nl -> {'comment': 'Workstation', 'dtap': 'prod'}

The fix

Detect .yml/.yaml and shell out to ansible-inventory -i <file> --list, which emits the same JSON structure as a dynamic inventory script — so the existing DynInvParser consumes it unchanged.

Error handling is a little firmer than the original: if ansible-inventory isn't on PATH we say Ansible needs installing rather than surfacing a bare OSError, and a non-zero exit relays its stderr and skips the inventory instead of feeding the parser empty output.

Reworked from the original

The upstream patch inserted a bare if ahead of the existing elif os.path.isfile(...):

if os.path.isfile(p) and util.is_executable(p):
    self._parse_dyn_inventory(p)
if os.path.isfile(p) and p.endswith(('.yml', '.yaml')):   # <-- new bare if
    self._parse_ansible_inventory(p)
elif os.path.isfile(p):
    self._parse_hosts_inventory(p)

That detaches the elif from the executable check, so an executable non-YAML inventory matches the dynamic-script branch and then the static-file branch, and gets parsed twice. This version uses elif so the chain stays exclusive.

I also dropped the original's proc.communicate(input), which passed the builtin input function.

Testing

Adds testYamlInventory with a YAML fixture, asserting both that real hosts and their vars are picked up and that YAML keywords don't leak in as hosts. It skips cleanly when ansible-inventory is unavailable, so it won't break environments without Ansible.

Full suite 10/10 pass. Regression-checked ini, directory, and executable dynamic inventories to confirm the dispatch chain still routes each correctly.

[Copilot]

Pull request overview

This PR adds first-class support for YAML (.yml/.yaml) Ansible inventory files by dispatching them to ansible-inventory --list and then reusing the existing dynamic-inventory JSON parsing path, preventing YAML keywords from being misinterpreted as hosts by the INI parser.

Changes:

• Route .yml/.yaml inventory files through ansible-inventory --list and ingest its JSON output.
• Add a YAML inventory fixture and a unit test to ensure real hosts/vars are parsed and YAML structural keywords do not appear as hosts.
• Improve error handling around invoking ansible-inventory (missing executable / non-zero exit).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
src/ansiblecmdb/ansible.py	Adds YAML inventory detection and a parser that shells out to ansible-inventory and feeds its JSON into DynInvParser.
test/test.py	Adds a skip-guarded unit test validating YAML inventory parsing behavior.
test/f_inventory/inventory.yml	Adds a YAML inventory fixture used by the new test.

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[gdevenyi]

Merge note: conflicts with #10 in ansible.py and test.py, whichever lands second.

test.py is trivial (keep both sides). ansible.py is not: this PR adds a YAML branch to the inventory dispatch chain and #10 makes the executable branch fall back to static parsing. Taking either side loses the other, and combining them naively sends a chmod +x'ed .yml to the ini parser — the exact bug this PR fixes.

The resolution that works is to factor the shared path into a _parse_static_inventory() helper called from both branches, which also fixes the executable-YAML case neither PR handles alone. Code in the guide: #1 (comment)

Clean against every other open PR.