molecule-verify

name	molecule-verify
description	Molecule verify assertion patterns. completeness requirements, batch operations, multi-node patterns.

Molecule Verify

Rules

1. Every configured feature MUST have assertion in verify.yml.
2. Assert IP non-empty and no collision BEFORE functional tests.
3. SINGLE pct config call per container, then assert on cached output.
4. Use ansible.builtin.uri → NM/SM API for runtime status checks. pct exec is ONLY for hypervisor-side operations that have no API equivalent.
5. NEVER use failed_when: false on client sends — let errors surface.
6. Per-feature verify MUST reconstruct dynamic groups (separate invocation).
7. Use the fleet readiness API as the sole path for container liveness: /api/fleet/ready, /api/container/{id}/ready, /api/config/self. NEVER add SSH fallback paths — if the API is unreachable, the 4-tier system is broken and must be fixed.
8. Hard-failure messages MUST include INVESTIGATE prompts with specific diagnostic steps (curl commands, journalctl checks, relay chain tracing).
9. All API calls in verify use vpn_ip for NM communication (VPN-only post-bootstrap). NEVER use ansible_host for API queries.

Completeness requirements

Per VM:

Category	Example assertions
VM state	Running, correct VMID
VM auto-start	onboot=1, startup order=N
NIC topology	net0 on correct bridge (WAN vs LAN)
Network config	WAN has IP, LAN subnet doesn't collide with WAN
Services	DHCP configured, firewall running
Optional features	MAC cloning (when WAN_MAC set), mesh (when WiFi present)
Backup	Manifest exists, has required fields, archive on disk
Deploy tracking	vm_builds.fact exists, contains expected plays
State files	.state/addresses.json exists, contains host + IPs

Per LXC:

Category	Example assertions
Container state	Running, correct VMID
Auto-start	onboot=1, startup order=N
Baked config	All baked config files exist inside container
Config validation	Service config passes validation (rsyslogd -N1, nginx -t)
Service state	systemctl is-active <service>
Network listener	Port is listening (ss -tlnp)
Functional test	Send data, verify received/processed
Multi-source test	Multiple senders/tags produce correctly separated output
No-leak test	Remote data stays in remote logs, not local syslog
Restart resilience	Stop/start service, verify listener and reception recover
Resource usage	Memory within allocation (free -m < allocated)
Logrotate	Config exists and passes logrotate --debug validation
Deploy stamp	stamp.plays contains the service entry

IP validation

- name: Read container config
  ansible.builtin.command:
    cmd: pct config {{ ct_id }}
  register: _ct_cfg
  changed_when: false

- name: Extract IP
  ansible.builtin.set_fact:
    _ct_ip: >-
      {{ _ct_cfg.stdout | regex_search('ip=([^/,]+)', '\1') | first }}

- name: Assert IP valid
  ansible.builtin.assert:
    that:
      - _ct_ip is defined
      - _ct_ip | length > 0

Batch pct config

ansible.builtin.command:
  cmd: pct config {{ ct_id }}
register: _ct_cfg

- name: Assert onboot
  ansible.builtin.assert:
    that: "'onboot: 1' in _ct_cfg.stdout"

Batch pct exec

ansible.builtin.shell:
  cmd: >-
    pct exec {{ ct_id }} -- /bin/sh -c '
    echo "IFACE=$(ip link show wg0 >/dev/null 2>&1 && echo ok || echo missing)";
    echo "SVC=$(systemctl is-enabled wg-quick@wg0 2>/dev/null || echo unknown)"
    '
  register: health
  changed_when: false

Client sends

# Let errors surface immediately
ansible.builtin.shell:
  cmd: logger --tcp {{ ct_ip }} 514 --server.host test

# Reserve failed_when: false for commands whose rc is checked by assertion

Service management

Prefer ansible.builtin.systemd over command: systemctl:

ansible.builtin.systemd:
  name: rsyslog
  state: restarted

Multi-node patterns

For 4-node tests, avoid IP recomputation. Read config once:

ansible.builtin.command:
  cmd: pct config {{ ct_id }}
register: _ct_cfg

ansible.builtin.set_fact:
  _ct_ip: >-
    {{ _ct_cfg.stdout | regex_search('ip=([^/,]+)', '\1') | first }}

Fact scoping

Facts from converge NOT available in verify. For roles with facts, re-include:

- name: Verify proxmox_igpu role
  hosts: proxmox
  gather_facts: true
  roles:
    - proxmox_igpu  # re-run to populate facts

No-leak testing

Verify remote messages don't pollute local logs:

- name: Send from remote
  ansible.builtin.shell:
    cmd: logger --tcp {{ remote_ip }} 514 "TEST-LEAK-{{ ansible_date_time.epoch }}"

- name: Verify no leak
  ansible.builtin.shell:
    cmd: grep "TEST-LEAK-{{ ansible_date_time.epoch }}" /var/log/syslog
  register: _leak
  failed_when: _leak.rc == 0

Verify task conventions

1. Fail-fast IP validation. Assert IP non-empty and no collision with host IP BEFORE functional tests. "IP is empty" is clear; "log not found" 10 tasks later is not.

2. No failed_when: false on client sends. Let logger --tcp, dig, curl fail immediately on connection error. "Connection refused" is far more useful than downstream "expected output not found."

3. set -o pipefail only on pipelines. NEVER add pipefail to single-command tasks. It adds noise and obscures the convention that pipefail signals a pipeline.

4. Use ansible.builtin.systemd over command: systemctl for restarts. Use command only for status checks and validation.

Jinja regex_search in assert

regex_search without a capture group returns a STRING match (not boolean). In assert: that: blocks, ALWAYS append is not none:

# BAD — returns string, assert sees "Conditional was derived from type str"
- _output | regex_search('RADIOS=phy')

# GOOD — explicit boolean
- _output | regex_search('RADIOS=phy') is not none

grep -c with find -exec in containers

When using find ... -exec grep -c 'pattern' {} + inside a container (via pct exec), grep -c outputs filename:count when multiple files match, but just count for a single file. Jinja2's | int filter returns 0 for filename:count strings, silently breaking assertions.

ALWAYS use grep -rch with awk sum instead:

# BAD — breaks when multiple files match
pct exec {{ ct_id }} -- find /var/log/remote/ -name '*.log' -exec grep -c 'pattern' {} + 2>/dev/null | head -1

# GOOD — numeric output regardless of file count
pct exec {{ ct_id }} -- grep -rch 'pattern' /var/log/remote/ 2>/dev/null | awk '{sum+=$1} END {print sum+0}'

Previous bug: rsyslog separation test used find -exec grep -c. On mesh1, multiple log files existed under different hostname directories. grep -c output /var/log/remote/home/e2e_daemon_a.log:11. Jinja2 | int converted this to 0, failing the assertion.

Host-to-container TCP fallback pattern

When verifying TCP-based services in containers, host-to-container TCP may fail on specific hosts (e.g., mesh1) even when ICMP ping succeeds and br_netfilter is disabled. Add a fallback path:

- name: Send log via host TCP
  ansible.builtin.shell:
    cmd: logger --tcp -n {{ container_ip }} -P 514 "test message"
  register: _send
  failed_when: false
  retries: 5
  delay: 5
  until: _send.rc == 0

- name: Diagnose TCP failure
  ansible.builtin.shell:
    cmd: |
      echo "=== nft ruleset ==="
      nft list ruleset 2>/dev/null | head -40
      echo "=== raw TCP ==="
      timeout 3 bash -c "echo test > /dev/tcp/{{ container_ip }}/514" 2>&1 && echo "ok" || echo "fail"
    executable: /bin/bash
  when: _send.rc != 0

- name: Fallback via pct exec
  ansible.builtin.shell:
    cmd: >-
      pct exec {{ ct_id }} --
      logger --tcp -n 127.0.0.1 -P 514 "test message"
  when: _send.rc  

Previous bug: mesh1 host consistently failed logger --tcp to its rsyslog container (10.10.10.14) despite ping succeeding and br_netfilter disabled. Root cause unresolved (likely nftables or conntrack). Fallback via pct exec with localhost TCP verifies rsyslog works without host-level network dependency.

Windows VM verification via QEMU Guest Agent

For Windows VMs without reliable SSH (no sshpass, LAN-only IPs), use qm guest exec instead of SSH connectivity tests:

- name: Test in-VM command via Guest Agent
  ansible.builtin.command:
    cmd: qm guest exec {{ vm_id }} --timeout 15 -- cmd /c "echo vm-ok"
  register: _exec_test
  changed_when: false
  failed_when: false

- name: Assert in-VM command works
  ansible.builtin.assert:
    that: "'vm-ok' in _exec_test.stdout"

For per-host VMID scenarios, compute the effective VMID at the start of verify:

- name: Set per-host VM ID
  ansible.builtin.set_fact:
    gaming_vm_id: "{{ (gaming_vm_id | int) + groups['gaming_nodes'].index(inventory_hostname) }}"

Previous bug: verify used sshpass for SSH testing. sshpass wasn't installed on mesh1. Switched to Guest Agent which bypasses network entirely.

DNS service verification (Pi-hole FTL)

ALWAYS check BOTH TCP and UDP listeners for DNS services. dig defaults to UDP. ss -tlnp only checks TCP — a service can bind TCP:53 but miss UDP:53 due to startup race or partial initialization.

- name: Wait for DNS on TCP+UDP port 53
  ansible.builtin.shell:
    cmd: >-
      pct exec {{ ct_id }} -- /bin/sh -c '
      tcp=$(ss -tlnp 2>/dev/null | grep -c ":53 ");
      udp=$(ss -ulnp 2>/dev/null | grep -c ":53 ");
      [ "$tcp" -gt 0 ] && [ "$udp" -gt 0 ] && echo BOTH || echo MISSING
      '
  retries: 6
  delay: 5
  until: "'BOTH' in _ftl_listen.stdout"

- name: Restart FTL if listeners are incomplete
  ansible.builtin.command:
    cmd: >-
      pct exec {{ ct_id }} -- /bin/sh -c
      'systemctl restart pihole-FTL && sleep 3'
  when: "'BOTH' not in _ftl_listen.stdout"

ALWAYS wrap DNS resolution tests in block/rescue. The retries/until pattern makes a task fatal when all retries expire — any diagnostic tasks after it never execute. Use block: for the test and rescue: for diagnostics + recovery (FTL restart + retry).

ALWAYS add a network connectivity pre-check before DNS tests: verify the container can ping its gateway and an external IP. This distinguishes "FTL is broken" from "container has no network."

Previous bug: Pi-hole DNS verify timed out in E2E tests. ss -tlnp | grep :53 passed (TCP listener present) but dig @127.0.0.1 timed out (UDP listener missing). FTL had TCP bound but UDP wasn't ready. Adding UDP check + automatic FTL restart fixed the intermittent failure.

Previous bug: DNS test used retries: 5 with until:. After all retries expired, the task failed fatally. Diagnostic tasks defined below it never executed. Switching to block/rescue ensures diagnostics always fire, and the rescue block restarts FTL + retries, recovering from transient upstream timeout.

Avoid regex_search on pct exec output

NEVER use regex_search with capture groups to parse pct exec output in set_fact or assert blocks. pct exec output passes through multiple shell layers (SSH → Proxmox host bash → lxc-attach → container shell) and may contain unexpected formatting, ANSI escapes, or extra whitespace that breaks regex matching.

Safe pattern: Use string-contains checks with in operator:

# BAD — crashes with 'NoneType' if regex returns None
- set_fact:
    val: "{{ output | regex_search('KEY=(\\S+)', '\\1') | first }}"

# GOOD — simple, robust, no crash risk
- assert:
    that: "'KEY=expected' in output"

# GOOD — for negation checks
- assert:
    that: "'KEY=0' not in output"

Previous bug: Batched rsyslog/gaming verify tasks used regex_search('MATCH=(\\S+)', '\\1') | first to extract values from pct exec output. The regex returned None on all 4 nodes, crashing set_fact with 'NoneType' object has no attribute 'group'. Replaced with string-contains checks.

Display-exclusive container assertions

When containers share a display device (iGPU DRI render node), a hookscript may stop one container when another starts (e.g., Kiosk stopped when Desktop LXC starts). Assert container config separately from running state:

- name: Assert container config is correct
  ansible.builtin.assert:
    that:
      - "'onboot: 1' in _cfg.stdout"
      - _cfg.stdout is regex('startup:.*order=6')

- name: Check if competing container is running
  ansible.builtin.command:
    cmd: pct status {{ desktop_ct_id }}
  register: _desktop_status
  changed_when: false
  failed_when: false

- name: Assert running OR stopped by hookscript
  ansible.builtin.assert:
    that: >-
      'running' in _cfg.stdout or
      ('stopped' in _cfg.stdout and 'running' in (_desktop_status.stdout | default('')))

Previous bug: Kodi and Kiosk assertions required 'running' state, but the display-exclusive hookscript correctly stopped them when the Desktop LXC started. Fix: accept 'stopped' when the competing container is running.

Multi-instance container IP from API

When the same container type deploys to multiple hosts (e.g., rsyslog on 4 nodes), the fleet API returns a single IP (last check-in) for all instances sharing the same container_id. ALWAYS use pct config for per-host container IPs in verify:

- name: Extract per-host container IP
  ansible.builtin.set_fact:
    _ct_ip: "{{ _ct_cfg.stdout | regex_search('ip=([^/,]+)', '\\1') | first }}"

Previous bug: rsyslog verify used API-returned IP for cross-service log tests. All 4 hosts got the same IP (10.10.10.14 — Home Assistant's IP), causing logger TCP to fail on 3 of 4 hosts. Fix: always use pct config for IP extraction.

systemd service state from callhome

callhome.py uses systemctl list-units which reports state as running (not active from systemctl is-active). Assertions against API systemd_services data MUST accept both values:

- _api.json.systemd_services.get('service', '') in ['active', 'running']

CRITICAL: Retries are a code smell — fix root causes, don't add wait time

NEVER use retries to paper over timing or infrastructure issues. Retries mask root causes and waste minutes per test cycle — compounding across every developer and every run.

The retry audit rule: Every retries: in verify.yml MUST have a comment explaining (1) what exact propagation delay it accounts for, and (2) the expected time. If you can't state both, the retry is hiding a bug.

Known propagation times (after relay interval fix):

• Container → NodeManager heartbeat: 5s (startup burst)
• NM → CM relay: 10s
• CM → SM relay: 10s
• Total container → SM: ~25s worst case
• Services already running by verify start: most checks should pass immediately

Hard rules:

• NEVER use retries > 6 for any check. If it doesn't work after 60s, it's broken.
• NEVER use delay > 10 for any check. Short polling finds fast successes.
• NEVER add retries when a service fails to start. Diagnose WHY it fails.
• REMOVE retries when the root cause is fixed. Zero retries is the ideal.
• NEVER add debug/diagnostic tasks as permanent verify fixtures. Fix the root cause, then remove the debug task.

Previous catastrophe (2026-04-14): kiosk-display-proxy on mesh1 was crash-looping with 957 restarts because a legacy kiosk-vnc-proxy from before the KasmVNC migration was still holding port 6080. Instead of diagnosing the root cause, retries were repeatedly increased (from 3×10s to 10×10s = 100 seconds). Debug tasks were added to capture systemctl show output. The SM heartbeat check used retries: 12, delay: 30 (6 MINUTES). The CM check was another 6 minutes. The verify phase alone burned 12+ minutes on retries that were NEVER going to succeed because the underlying issue was a port conflict, not timing.

Fix: (1) Added legacy VNC proxy cleanup before deploying new display proxies — service now starts on first attempt with zero retries. (2) Reduced relay heartbeat interval from 30s to 10s — SM/CM heartbeats arrive within seconds of verify starting, not minutes. (3) SM and CM checks: retries: 6, delay: 10 (60s max vs 360s before). Both now succeed on the FIRST attempt.

The real cost: These retries were silently burning 12+ minutes on EVERY molecule test run. Over dozens of test cycles, that's HOURS of wasted time. And the retries never surfaced the root cause — they just delayed the inevitable failure.

Common failures

• 0 assertions ran → dynamic group empty (add reconstruction)
• Rollback targets 0 hosts → empty group in cleanup
• igpu_available not defined → re-include role in verify
• Wrong IP for WAN hosts → use pct config extraction
• Per-feature scenario missing router_nodes group → LAN/WAN detection takes wrong path
• Register result used as string → ALWAYS use _var.stdout | trim, not _var directly. Register results are dicts, not strings. Previous bug: _jellyfin_verify_ip.split('.') failed because _jellyfin_verify_ip was a register result (dict), not the stdout string.
• set -o pipefail on non-pipeline commands → use ansible.builtin.command for single commands without pipes. Pipefail on non-pipeline commands adds noise and obscures the convention that pipefail signals a pipeline.
• config_files[path].keys() returns a method, not a list → use config_files[path]['keys'] to access the stored key list from callhome extensions.