signalk-slack-notify

Send Signal K notifications to Slack through an incoming webhook.

Create Slack account and private free Workspace

https://app.slack.com/get-started#/createnew

• Make you own Slack workspace
• Add #alert channel
• Select alert levels

Make a Bot

https://api.slack.com/apps

• Create A New App (From scratch)
• Name Your bot & pick your workplace

Basic Information

• Configure "Display Information"
• Add "Incoming Webhooks"

Incoming Webhooks

• Activate Incoming Webhooks
• Add "Add New Webhook to Workspace"

Test post

• Select channel, e.g. #alerts -> Allow
• Copy Webhook URL (will be used in SIgnal K plugin)

Signal K Plugin Config

Signal K notifications to Slack

• Paste Slack Webhook URL to plugin config
• Add message title
• Add Slack channel, default #alert
• Select alert levels to send

Behaviour

State change deduplication

Slack notifications are only sent when a notification's state actually changes. If Signal K repeatedly delivers the same state for a path (e.g. alarm → alarm → alarm), only the first occurrence triggers a Slack message. A new message is sent as soon as the state transitions to a different value (e.g. alarm → warn or alarm → normal).

State history is reset when the plugin stops or restarts, so the first notification after a restart always fires.

Development

• npm install
• npm run format checks formatting
• npm run lint runs ESLint
• npm run typecheck runs strict TypeScript checks
• npm test runs the Node test suite
• npm run build compiles the plugin to dist/
• npm run audit fails on high or critical vulnerabilities
• npm run verify runs the full release-readiness gate: format, lint, typecheck, tests, build, audit, and npm pack --dry-run