Integrate pdfRest with Bubble to Automate PDF Workflows

Bubble.io is a powerful no-code/low-code platform that lets you build and launch fully functional web applications visually, without writing any traditional code. Using its built-in API Connector plugin, you can connect your app to external APIs like pdfRest to create powerful, automated document workflows.

To get started, sign up for a free Starter account with pdfRest to generate your dedicated API Key. You’ll use this key to authenticate requests from Bubble.io.

Tutorial: Enhancing Your Bubble App with pdfRest

Objective

This tutorial will demonstrate how to:

1. Install and configure the Bubble.io API Connector for pdfRest.
2. Create Bubble visual elements for file upload and action buttons.
3. Call pdfRest APIs for Upload, Convert to PDF/A, and Merge PDFs.
4. Configure workflows to trigger the API calls and provide links to download your new files.

Step 1: Install and Configure the API Connector Plugin

• In the Bubble Editor, open the Plugins tab, and select Add plugins.
• Search for and install the API Connector.
• Create a new API named pdfRest.

In the API setup:

• Add a Shared header for authentication:
  • Key = Api-Key
  • Value = your pdfRest API key
  • Check the box to mark this as PRIVATE

• For each endpoint, add a new POST call:
  • Upload API → POST https://api.pdfrest.com/upload
  • Convert to PDF/A API → POST https://api.pdfrest.com/pdfa
  • Merge PDFs API → POST https://api.pdfrest.com/merged-pdf
• Set the Body type as Multipart/form-data
• Ensure responses are returned in JSON for easy parsing

Step 2: Define Your Desired API Endpoint Parameters

Each endpoint requires specific parameters in its API call. Click the name of the APIs below for direct links to their documentation.

• Upload API
  • Parameters
    • file: The file to be uploaded to the pdfRest server
    • url: The URL of a file publicly available on the internet to upload to the pdfRest server

• Convert to PDF/A API
  • Parameters:
    • One of:
      • file: The file to be sent in the request's form data (dynamic)
      • id: The id of the uploaded file on the pdfRest server (dynamic)
    • output_type: The desired PDF/A type for the output file (optional)
    • rasterize_if_errors_encountered: Whether a page should be rasterized in the event an error is encountered (optional)
    • output: The name of the output file (optional)

• Merge PDFs API
  • Parameters
    • id: The list of file id's uploaded to the pdfRest server
      • For id's value, use <idX> where X is the number of the file, as shown in the image below. You may use as many <idX>'s as you like, but remember to include the same amount of values for the type and pages lists!
    • type: The list of input types for the given documents
      • Either file or id, but for the purposes of this example they will all be id
    • pages: What pages of each document should be in the final merged document (for this example, 1-last uses all pages).

If you'd like to use a tool that isn't explicitly shown here, most tools can be easily added simply by defining the parameters as shown in the pdfRest API Toolkit Reference Guide.

Step 3: Create Visual Elements in Bubble

1. On your page, drag out a Group. This will contain the UI for the file action.
2. Inside the Group, add a File Uploader element. This lets users select a PDF. For merging PDFs, use two or more File Uploader elements.
3. Add a Dropdown if you want the user to select options (e.g., PDF/A conformance level via the output_type parameter).
4. Add a Button (e.g. “Convert to PDF/A” or “Merge PDFs”).

These elements will connect to workflows that call the pdfRest API.

A simple visual implementation of Convert to PDF/A might look like the following:

For defining the options in the drop down, make sure to match the values exactly as defined in the Convert to PDF/A documentation.

A simple implementation of a Merge PDFs workflow might look like the following:

Note that this uses two File Uploader components. You can customize this with as many as required for your particular implementation.

Step 4: Configure Workflows

For each button, create a Workflow that connects the visual elements to the API calls:

Convert to PDF/A Workflow

A workflow for Convert to PDF/A might look like the following:

To accomplish this, define the following:

• Click the + button, hover over Plugins, and select pdfRest - PDF/A from the options.
• Pass the file from the FileUploader for your PDF/A group.
• Also pass the output_type value from the Dropdown element you created earlier
  • Include any other optional values, such as rasterize_if_errors_encountered if you'd like to dynamically change the value from its default.

• Finally, click the + button again and choose Navigation -> Open an external website
  • Here, you can use the Result of step 1 (pdfRest - PDF/A)'s outputUrl
  • If configured in this way, it will open the processed PDF into a new tab

Merge PDFs Workflow (Backend)

A Workflow for Merge PDFs might look like the following:

Before any other configuration, we'll define a new Data type called OutputFile. This will contain the url of the processed output file.

• Choose the Data tab in the navigation on the left side of the screen
• In the New type field, enter OutputFile

• Add a Field on OutputFile called url

Back in the Workflow tab, define the following:

• Click the + button, then choose Plugins -> pdfRest - Upload.
• Set either the url or file parameter to the user inputs (for the purposes of this example, file is used).
  • Repeat the above step for however many files the user is merging together.

• Click the + button, then choose Plugins -> pdfRest - Merge.
• Define the id for each uploaded file with Result of step X (pdfRest - Upload)'s files: first item's id.
  • Make sure you choose first item's id, as there will always only be one item in the files array from each Upload call.
  • Note that for the purposes of this example, there are only two files, but this can be expanded to your needs.

• To use a Download File button, click the + button and choose, Data (Things) -> Create a new thing...
  • Choose the Data type OutputFile that was defined earlier
  • Set the url to be equal to Result of step 3 (pdfRest - Merge)'s outputUrl
• Finally, click the + button and choose, Element Actions -> Display data in a group/popup
  • Set the Element to Group OutputFile, and Data to Display as Result of Step 4 (Create a new OutputFile...)

When configured correctly, the Download button should then take you to the URL of the newly merged documents.

Conclusion

By installing the API Connector, creating visual elements, and configuring workflows, you’ve now linked Bubble.io to the pdfRest API Toolkit's Upload, PDF/A, and Merge PDFs endpoints. The pdfRest API Toolkit includes many tools for Compression, Security, Digital Signatures, and so much more that can be connected in similar fashion.

Once you’ve mastered this foundation, you can extend your Bubble.io app into a complete document automation platform! Sign up for a free pdfRest Starter account and start exploring the possibilities.