Slack and Discord bridge

Bridge external chat platforms into FluxyChat rooms with two-way channel mappings: room messages are delivered out to the platform, and signed webhooks sync replies back.

Manage bridges from the dashboard Bridges page or the admin REST API.

Create a bridge

curl -X POST "$WORKER_URL/admin/bridges" \
  -H "Authorization: Bearer $ADMIN_JWT" \
  -H "Content-Type: application/json" \
  -d '{
    "platform": "slack",
    "name": "Support Slack",
    "token": "xoxb-...",
    "signingSecret": "a1b2c3..."
  }'

Supported platforms: slack, discord.

• token (optional) is the bot token used for outbound delivery.
• signingSecret (optional, but inbound returns 503 without it) is the Slack signing secret or the Discord application public key.
• Both secrets are encrypted at rest when the worker has WEBHOOK_SECRET_ENCRYPTION_KEY configured.

Rotate or add secrets later without recreating the bridge (recreating deletes its mappings and message map):

curl -X PATCH "$WORKER_URL/admin/bridges/br_abc123" \
  -H "Authorization: Bearer $ADMIN_JWT" \
  -H "Content-Type: application/json" \
  -d '{ "signingSecret": "rotated-secret" }'

Inbound webhook URLs

Point your Slack Event Subscriptions or Discord interactions endpoint at:

Inbound requests are verified before parsing:

• Slack: x-slack-signature (v0 scheme); x-slack-request-timestamp must be within 5 minutes.
• Discord: x-signature-ed25519 over {timestamp}{body}.

Failures are fail-closed: 401 for a bad or stale signature, 503 signature_not_configured when the bridge has no secret. Slack URL verification (url_verification challenge) is answered after the signature check.

Channel mappings

Map an external channel ID to a FluxyChat room:

curl -X POST "$WORKER_URL/admin/bridges/mappings" \
  -H "Authorization: Bearer $ADMIN_JWT" \
  -H "Content-Type: application/json" \
  -d '{
    "bridgeId": "br_abc123",
    "roomId": "room_support",
    "externalChannelId": "C01234567",
    "externalChannelName": "#support",
    "syncDirection": "both"
  }'

syncDirection accepts both (default), inbound, or outbound.

Outbound delivery

Messages sent in a mapped room of a connected bridge are queued in bridge_deliveries and delivered with the bridge credentials:

• Slack: chat.postMessage with the bot token, or the configured webhookUrl (incoming webhook) when no token is set.
• Discord: POST /channels/{channel_id}/messages with the bot token, or the configured webhook URL.

Failures retry with backoff (60s, 5m, 30m, 1h) on the webhook-flush cron until BRIDGE_MAX_ATTEMPTS (default 5), then land as failed with the provider error surfaced on the bridge. Inspect the last 20 deliveries:

curl "$WORKER_URL/admin/bridges/br_abc123/deliveries" \
  -H "Authorization: Bearer $ADMIN_JWT"

Messages imported from a platform are never echoed back to that same platform.

Connect and monitor

# List bridges
curl "$WORKER_URL/admin/bridges" -H "Authorization: Bearer $ADMIN_JWT"

# Connect / disconnect
curl -X POST "$WORKER_URL/admin/bridges/br_abc123/connect" \
  -H "Authorization: Bearer $ADMIN_JWT"

# Stats
curl "$WORKER_URL/admin/bridges/stats" -H "Authorization: Bearer $ADMIN_JWT"

Troubleshooting

• 503 on webhook — no signing secret configured. Add one from the dashboard (Secrets) or with PATCH.
• 401 on webhook — signature mismatch or a Slack timestamp older than 5 minutes.
• 404 on webhook — verify bridgeId and platform match (slack bridge only accepts the /slack/ path).
• Messages not appearing inbound — confirm a mapping exists for the external channel_id and the bridge status is connected.
• Outbound stuck pending or failed — check GET /deliveries for lastError; delivery needs a bot token or a webhook URL.
• Slack duplicates — ignore bot subtypes; the parser skips message events with subtype.

See also Webhooks catalog for delivery signing and replay tooling, and Matrix bridge for federation.