Skip to content

Connector event triggers

A connector trigger starts a workflow when something happens in a connected service: a finished Granola meeting note, a Slack message, a new Databricks job run.

Connector triggers come in two kinds. Push triggers receive events the service sends to Flero, within seconds. Polling triggers ask the service for new items on an interval.

For the triggers each connector offers, see its page in the Connector catalog.

Push (real-time) triggers

Connector Triggers What you need
Granola Note generated, Note edited, Note shared with me A Granola API key on a Business or Enterprise plan
Slack New message, Slash command, Button clicked A Slack app owned by your Slack workspace, created through Add Flero to Slack. Limited availability.

Other connectors, Microsoft Outlook included, offer polling triggers only.

The events URL

Each credential gets one events URL. Every active workflow whose push trigger uses that credential shares it. The URL looks like:

https://acme.flero.ai/trigger/connector/<token>

The trigger panel shows it under Events URL, with a status line:

  • Granola: Flero registers the URL with Granola for you when you publish a workflow that uses the trigger. The panel then says "Flero registered this events URL with Granola".
  • Slack: the URL is built into the Slack app that Add Flero to Slack creates. The panel shows whether Slack has verified it.

Verification

Flero checks every push delivery before anything runs:

Connector Check
Slack Slack's request signature, made with your app's signing secret, no older than five minutes
Granola Standard Webhooks signature with the secret Granola issued at registration, no older than five minutes

A delivery that fails the check gets 401 and starts nothing. Services retry deliveries. Flero drops a repeat of the same delivery that arrives within 15 minutes.

Turning off

Setting the workflow inactive stops it from running. The registration at the service stays in place:

  • Granola: the webhook endpoint stays registered. Deliveries with no active workflow start nothing.
  • Slack: the app stays installed. Events with no active workflow start nothing, and a slash command with no active workflow gets a private reply saying so.

Polling triggers

Most connectors offer polling triggers built from their list and get operations, for example List runs on Databricks or Get Many messages on Outlook. Each poll calls the operation and starts a run when there are new items.

Setting Notes
Credential The stored credential for the service.
Event Which operation to poll.
Poll interval 1m, 5m (default), 15m, 30m, 1h, 6h or 24h.
Polling mode On change (default) fires only for items Flero has not seen before. Continuous fires for every item returned, on every poll.

The operation's own fields, such as a folder or a job filter, appear below these.

How polling behaves

  • The first poll counts everything as new. On activation, every item on the first page of results is new, so the first run can carry items that already existed.
  • One run per poll. A poll that finds five new items starts one run carrying all five, unless the trigger says it fires once per item.
  • A runaway trigger pauses itself. If a polling trigger fires more than 20 times in 5 minutes, Flero stops firing it for 15 minutes.
  • Polls are API calls. They count against the service's rate limits. Use a longer interval for services with tight limits.
  • Do not poll an action. Some connectors list operations that create, send or move things as polling triggers. Polling one performs the action on every poll. Pick a list or get operation.

Reading the trigger output

The trigger node outputs the items for this run. Read them from the node, using your trigger node's name:

{{ $node["Granola Trigger"].output.note_id }}
{{ $node["Slack Trigger"].output.text }}

Push deliveries often carry only an id. Chain a connector action to fetch the full record, for example Granola → Get note.

Availability

Some connector triggers are in limited release and do not appear in the node palette for every workspace. The connector catalog marks them. Where a connector has no usable trigger, a Schedule trigger followed by the connector's list operation does the same job.

Troubleshooting

Symptom Check
Push trigger never fires Is the workflow active? Does the panel say the events URL is registered or verified? For Granola, does your plan include webhooks?
Slack events URL stays "waiting for verification" Open the Slack app's Event Subscriptions page and click Verify.
Slack trigger ignores a channel Invite the app to private channels with /invite @<app name>. Public channels you pick are joined automatically.
First polling run has old items Expected on the first poll. Filter them out, or start the workflow once and discard that run.
Polling trigger stopped firing for a while It fired more than 20 times in 5 minutes and paused for 15 minutes. Lengthen the interval or narrow the filter.

Found something out of date? This page lives in the Flero docs content set.