TwiML Redirect Widget

Studio uses Widgets to represent various parts of Twilio's functionality that can then be stitched together in your Studio Flow to build out robust applications that require no coding on your part.

The TwiML Redirect Widget allows you to redirect a call or message to TwiML hosted somewhere other than your Studio Flow and, optionally, return control of the call back to Studio after the TwiML you redirect to is complete.

The URL you redirect to with this Widget must host valid TwiML. TwiML can be hosted and served in many ways, including but not limited to:

• As a static asset served by your own server
• As a Serverless Asset
• In a TwiML Bin (supports mustache templates)
• As the result of calling a Serverless Function

Required configuration for TwiML Redirect

The TwiML Redirect Widget requires only one piece of information to function properly:

Note: Studio does not actually make the HTTP request to this URL. Instead, Studio prints the TwiML, which instructs Twilio Voice or Messaging to make a new request to the URL you specify.

How to pass parameters to a TwiML Redirect URL

If you want to pass parameters to a TwiML Redirect URL from your Studio Flow, you can pass them in a query string as part of your URL.

For example, if you want to pass the Digits variable from the Gather widget, you should enter the following in the URL field for the TwiML Redirect widget:

https://example.com/myfunction?Digits={{widgets.MY_WIDGET_NAME.Digits}}

How to return control to Studio

To return control of the call or message to Studio, you must specify a <Redirect> to your Studio Webhook URL and append ?FlowEvent=return. Studio will inject any additional parameters specified in the return URL to your Studio context. These parameters will then be available in your Studio Flow via Liquid template variables.

Example:

<Response>
  <Say>Returning you back to the Studio Flow.</Say>
  <Redirect>https://webhooks.twilio.com/v1/Accounts/{AccountSid}/Flows/{FlowSid}?FlowEvent=return&amp;foo=bar</Redirect>
</Response>

The URL parameter foo illustrated above will be passed automatically into your Flow and can be referenced via Liquid as {{widgets.your_redirect_widget_name.foo}}.

Tip: To retrieve the Studio Webhook URL in your Studio flow, click the red Trigger widget. The URL starting with https://webhooks.twilio.com/v1/... is the Webhook URL for this Flow.

Optional configuration for TwiML Redirect

The TwiML Redirect Widget accepts a few configuration options that you can use to further customize how Studio redirects to your URL that hosts TwiML, and returning control back to Studio:

TwiML Redirect Transitions

These events trigger transitions from this Widget to another Widget in your Flow:

Regaining control of a Voice call

Please note that your Studio Flow will not be able to regain control of a Voice call that is timed out after passing the call to your TwiML Redirect URL. The only way your Studio Flow can regain control of a Voice call that has been passed to a TwiML URL is if you first append the parameter FlowEvent=return to your URL. This will tell the TwiML that executes to return control back to Studio when execution is complete.

Learn more

Want to learn more about how you can use TwiML Redirects to customize your Studio Flow? Check out these guides:

• Learn how to write TwiML for handling Voice calls
• Learn how to write TwiML for handling messages
• Learn how to use a TwiML Bin to host serverless TwiML that your Studio Flow can use
• Learn how to use Twilio Functions to enhance Studio Voice calls with custom TwiML

We can't wait to see what you build!