docs: embedded MQTT broker — configurator option, feature docs, blog post

[Yeraze]

Summary

Documentation pass for the embedded MQTT broker feature that landed in #3053 + #3054 (resolving #3003).

• Docker Configurator — new "Expose embedded MQTT broker (port 1883)" toggle under section 8, with an info-box and a coexistence note for users who also have the MQTT Proxy sidecar checked. Emits - "1883:1883" on the meshmonitor service when on.
• docs/features/mqtt-broker.md — full feature page: the two source types, the two device paths (direct TCP and mqttClientProxyMessage client-proxy), filter semantics, quick-setup walk-through, comparison table against the MQTT Proxy Sidecar and node's built-in MQTT, troubleshooting, limitations. Linked from the Features sidebar.
• docs/add-ons/mqtt-proxy.md — info callout at the top pointing readers at the new built-in alternative, with a deep-link to the comparison table.
• docs/blog/2026-05-17-embedded-mqtt-broker.md — release announcement following the established blog-post format (frontmatter with id/title/date/category/priority/minVersion).

Fact-check notes

Every external claim was cross-referenced before drafting:

• Aedes 1.0.2 / MQTT.js 5.15.1 — confirmed against package.json in main (grep '"aedes\|mqtt"' package.json).
• MqttClientProxyMessage protobuf — confirmed against protobufs/meshtastic/mesh.proto (vendored submodule). Has topic + payload_variant oneof (data bytes or text string). Linked the upstream URL on github.com/meshtastic/protobufs.
• proxy_to_client_enabled — confirmed against protobufs/meshtastic/module_config.proto field 9 on the MQTT module config. Quoted the upstream comment verbatim.
• ServiceEnvelope — confirmed in protobufs/meshtastic/mqtt.proto.
• Port 1883 — referenced the IANA service-names port-number registry directly.
• PR / issue numbers (Feature: Built-in MQTT broker/proxy with topic and geographic filtering #3003, feat(mqtt): embedded MQTT broker + bidirectional bridges (#3003) #3053, feat(mqtt): bridge mqttClientProxyMessage to embedded broker (#3003 follow-up) #3054, ci(system-tests): fail-fast on first failing test; drop retry attempt #3060) — confirmed via gh pr view / gh issue view.
• mqtt.meshtastic.org default public broker + meshdev / large4cats subscriber credentials — referenced upstream docs at meshtastic.org/docs/configuration/module/mqtt/.

Version placeholder

The blog post and the feature-doc admonition use 4.6.0 as the minimum version. The active release PR is #3059 (4.5.3, doesn't include the MQTT broker). Adjust the version label before publishing if the feature ships under a different number — the placeholder is in three places:

• docs/blog/2026-05-17-embedded-mqtt-broker.md frontmatter minVersion: 4.6.0
• docs/blog/2026-05-17-embedded-mqtt-broker.md title "MeshMonitor 4.6 — …"
• docs/features/mqtt-broker.md admonition "Added in 4.6"
• docs/add-ons/mqtt-proxy.md admonition "Built-in alternative since 4.6"

Test plan

• All five files lint-clean (markdown + Vue + TypeScript).
• No new broken internal links — all /features/mqtt-broker, /configurator, /add-ons/mqtt-proxy, /features/multi-source, /features/device paths already exist.
• Visual review of the configurator section in a dev VitePress server (reviewer to confirm the new checkbox + info-box render cleanly).

🤖 Generated with Claude Code

[github-actions]

Claude finished @Yeraze's task —— View job

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PR Review: Embedded MQTT Broker Documentation

Comprehensive review of this documentation PR for the embedded MQTT broker feature.

Review Summary

This is a high-quality documentation PR that properly documents the new embedded MQTT broker feature. The code changes are clean and the documentation is comprehensive.

✅ Strengths

Vue Component (DockerComposeConfigurator.vue):

• ✅ Excellent Vue 3 Composition API usage - Clean reactive refs, computed properties, and proper event handling
• ✅ Smart dependency handling - Lines 667-671 automatically enable Virtual Node when MQTT Proxy is selected
• ✅ Clear user guidance - Lines 504-516 provide comprehensive setup instructions with external links
• ✅ Proper Docker configuration - Lines 776-779 correctly expose port 1883 with descriptive comment
• ✅ Coexistence awareness - Lines 528-531 warn users about potential overlap with MQTT Proxy sidecar

Documentation Quality:

• ✅ Comprehensive feature documentation - /docs/features/mqtt-broker.md covers all aspects thoroughly
• ✅ Proper cross-referencing - Links between related docs are accurate and helpful
• ✅ Well-structured blog post - Follows established format with proper frontmatter
• ✅ Good comparison tables - Clear feature comparison between alternatives
• ✅ Troubleshooting section - Addresses common setup issues

⚠️ Minor Issues

Code Quality:

• Template complexity - The section numbering logic using ternary operators (lines 174, 195, 245, 403, 569 in DockerComposeConfigurator.vue) makes maintenance harder. Consider a computed property for cleaner section numbering.

Documentation:

• Version placeholder consistency - The PR description mentions 4.6.0 version placeholders need adjustment if the feature ships under a different version number

🔒 Security Assessment

• ✅ No credential exposure - Passwords properly handled through .env file generation
• ✅ Proper port binding - MQTT broker port exposure is opt-in via checkbox
• ✅ No XSS vulnerabilities - Template uses proper Vue binding and escaping
• ✅ No raw SQL or injection risks - This is documentation-only

📋 Test Coverage Assessment

• ✅ Appropriate for documentation PR - No unit tests needed for docs changes
• ✅ Vue component follows existing patterns - Uses same reactive patterns as rest of configurator
• ✅ Author verified fact-checking - PR description shows thorough verification of external claims

🎯 Performance Considerations

• ✅ Minimal performance impact - Only adds conditional template rendering
• ✅ Proper form reactivity - No unnecessary re-renders or computations

📝 Recommendations

1. Consider refactoring section numbering in DockerComposeConfigurator.vue:174+:

   const sectionNumber = computed(() => ({
     ports: config.value.deploymentMode === 'production-proxy' ? 5 : 4,
     security: config.value.deploymentMode === 'production-proxy' ? 6 : 5,
     // ... etc
   }))

2. Version number coordination - Remember to update the version placeholders mentioned in the PR description when the release version is finalized.

🏁 Overall Assessment

This is an exemplary documentation PR that thoroughly covers a complex new feature. The Vue component changes are well-implemented with good UX considerations. The documentation is comprehensive, well-structured, and properly cross-referenced. No blocking issues found.

Recommendation: ✅ APPROVE - This PR is ready to merge.

---

[github-actions]

Claude finished @Yeraze's task —— View job

---

PR Review: Embedded MQTT Broker Documentation

Comprehensive review of this documentation PR for the embedded MQTT broker feature.

Review Summary

This is a high-quality documentation PR that properly documents the new embedded MQTT broker feature. The code changes are clean and the documentation is comprehensive.

✅ Strengths

Vue Component (DockerComposeConfigurator.vue):

• ✅ Excellent Vue 3 Composition API usage - Clean reactive refs, computed properties, and proper event handling
• ✅ Smart dependency handling - Lines 667-671 automatically enable Virtual Node when MQTT Proxy is selected
• ✅ Clear user guidance - Lines 504-516 provide comprehensive setup instructions with external links
• ✅ Proper Docker configuration - Lines 776-779 correctly expose port 1883 with descriptive comment
• ✅ Coexistence awareness - Lines 528-531 warn users about potential overlap with MQTT Proxy sidecar

Documentation Quality:

• ✅ Comprehensive feature documentation - /docs/features/mqtt-broker.md covers all aspects thoroughly
• ✅ Proper cross-referencing - Links between related docs are accurate and helpful
• ✅ Well-structured blog post - Follows established format with proper frontmatter
• ✅ Good comparison tables - Clear feature comparison between alternatives
• ✅ Troubleshooting section - Addresses common setup issues

⚠️ Minor Issues

Code Quality:

• Template complexity - The section numbering logic using ternary operators (lines 174, 195, 245, 403, 569 in DockerComposeConfigurator.vue) makes maintenance harder. Consider a computed property for cleaner section numbering.

Documentation:

• Version placeholder consistency - The PR description mentions 4.6.0 version placeholders need adjustment if the feature ships under a different version number

🔒 Security Assessment

• ✅ No credential exposure - Passwords properly handled through .env file generation
• ✅ Proper port binding - MQTT broker port exposure is opt-in via checkbox
• ✅ No XSS vulnerabilities - Template uses proper Vue binding and escaping
• ✅ No raw SQL or injection risks - This is documentation-only

📋 Test Coverage Assessment

• ✅ Appropriate for documentation PR - No unit tests needed for docs changes
• ✅ Vue component follows existing patterns - Uses same reactive patterns as rest of configurator
• ✅ Author verified fact-checking - PR description shows thorough verification of external claims

🎯 Performance Considerations

• ✅ Minimal performance impact - Only adds conditional template rendering
• ✅ Proper form reactivity - No unnecessary re-renders or computations

📝 Recommendations

1. Consider refactoring section numbering in DockerComposeConfigurator.vue:174+:

   const sectionNumber = computed(() => ({
     ports: config.value.deploymentMode === 'production-proxy' ? 5 : 4,
     security: config.value.deploymentMode === 'production-proxy' ? 6 : 5,
     // ... etc
   }))

2. Version number coordination - Remember to update the version placeholders mentioned in the PR description when the release version is finalized.

🏁 Overall Assessment

This is an exemplary documentation PR that thoroughly covers a complex new feature. The Vue component changes are well-implemented with good UX considerations. The documentation is comprehensive, well-structured, and properly cross-referenced. No blocking issues found.

Recommendation: ✅ APPROVE - This PR is ready to merge.