Suspend and Resume
Flows can be suspended until resumed or cancelled event(s) are received. This feature is most useful to implement approval steps but can be used for other purposes as well.
You can find ready-to-use Approval Scripts on Windmill Hub. For example:
Add Approval Script
You can think of a scenario where only specific people can resume or cancel a Flow. To achieve this they would need to receive a personalized URL via some external communication channel (like e-mail, SMS or chat message).
Important thing to remember is that the number of required approvals can be customized. This allows some flexibility for cases where you either require approvals from all authorized people or only from one.
Example with Gmail
Add Gmail Resource
Lets start with adding a Gmail Resource. On the
Resources page, click "Add a
resource/API", select the gmail OAuth API and click "Sign in with Google".
As Google is an OAuth provider, you will be redirected to select your Google account. To make the Approval Script work, you need to sign in and allow Windmill to send e-mails on your behalf.
Reusing Script from Windmill Hub
Let's create a Flow as described in the
getting started section.
Our first step will be an Approval Script from
Windmill Hub, so click the + sign in the left pane
and select "Approval (Script)".
Once the step is added, you'll be presented with some pre-made Scripts from the Hub. Select the one named "Suspend/resume a flow by sending approval URL via email (gmail)".
Make sure to fill required fields: for gmail_auth, select your newly added
Gmail resource and define email addresses in the approver_emails input.
Run the Flow
For the sake of this example let's add a "dummy" Script as a second step in our Flow.
The Flow is now ready for testing, let's click "Test flow" in the top-right corner.
You can notice that after the first step, the Flow is suspended and is waiting for approval. An e-mail should have been sent to the email addresses you specified. It contains a link to a webpage that looks like the following:
Let's approve and resume the Flow and see that it has successfully ran the second step as well.
