File Uploader workflow arriving null

Need help APIs
1

How do I pass a FileUploader element’s URL to an API Connector call in a workflow? The value is arriving as null when I try to use FileUploader A’s value’s URL in the API call body. What’s the correct way to capture and pass a file URL from a FileUploader to an external webhook?

2

✦ AI

The most likely reason you’re getting null for FileUploader A's value's URL in your API Connector call is timing: the file upload isn’t always finished by the time your workflow tries to use its URL. Here’s how to make sure you’re capturing and passing the file URL correctly:

How to do it:

  1. Trigger the workflow only after upload is complete
  • In the Workflow tab, use the event “When FileUploader A’s value is changed”. This event only fires after the file has finished uploading and Bubble has the file’s URL.
  • Don’t trigger the API call from a button click unless you’re sure the upload is done.
  1. Reference the file’s URL in the API call
  • In your API Connector action (in the workflow), set the relevant parameter or body field to:
    FileUploader A's value's URL
  • This will be the full S3 (or storage) URL of the uploaded file.
  1. If you need to trigger from a button (e.g., “Submit”)
  • Make sure the file is uploaded before the button is clickable. You can do this by:
  • Disabling the button until FileUploader A's value is not empty.
  • Or, show a loading indicator until the upload is done.

If you’re still getting null:

  • Check the workflow event: If you’re using “When Button is clicked”, and the file is still uploading, FileUploader A's value will be empty or null.
  • Check privacy rules: If you have privacy rules on the File data type, make sure the current user is allowed to see the file’s URL.
  • Check the API Connector call: Make sure you’re referencing the correct dynamic value in the body/parameter field.

Summary of steps in Bubble UI:

  • Go to the Workflow tab.
  • Add a new event: Elements → An input’s value is changed → FileUploader A.
  • Add an action: Plugins → Your API Connector call.
  • In the API call’s body/parameter, use: FileUploader A's value's URL.

If you need to use a button:

  • In the button’s workflow, add an “Only when” condition:
    FileUploader A's value is not empty
  • Or, disable the button until the file is uploaded:
    In the button’s “This element is clickable” property, set:
    FileUploader A's value is not empty

Less likely, but possible:

  • If you’re using a multi-file uploader, you’ll need to use FileUploader A's value's URL:first item or loop through the list.
  • If you’re using a custom file upload plugin, the property name might be different.

Let me know if you’re triggering the workflow from a button or another event — that’s usually the key detail here.