Search and Redact PDFs

Document Engine lets you create redactions using simple text search rules. Any piece of text matching a provided query will be covered by redaction annotations. To create redactions, use the createRedactions action with a text strategy.

To learn more about redaction strategies, go to the API Reference.

You can configure some visual aspects of the redaction annotation, including its background color and overlay text, by passing an optional content object to the createRedactions action. To learn more about all configurable options, refer to the API Reference.

The following example redacts any occurrence of the phrase ACME Bank:

{
  "type": "createRedactions",
  "strategy": "text",
  "strategyOptions": {
    "text": "ACME Bank"
  }
}

Applying Redactions

After redaction annotations are created, they need to be applied to the document to effectively and permanently remove the covered content. You can achieve this by adding the applyRedactions action to the /build instructions.

Before you get started, make sure Document Engine is up and running.

You’ll be sending multipart POST requests with instructions to Document Engine’s /api/build endpoint. To learn more about multipart requests, refer to our blog post on the topic, A Brief Tour of Multipart Requests.

Check out the API Reference to learn more about the /api/build endpoint and all the actions you can perform on PDFs with Document Engine.

Creating and Applying Redactions in a File on Disk

Send a multipart request to the /api/build endpoint attached with the input file and the instructions JSON:

curl -X POST http://localhost:5000/api/build \
  -H "Authorization: Token token=<API token>" \
  -F file=@/path/to/example-document.pdf \
  -F instructions='{
  "parts": [
    {
      "file": "document",
      "actions": [
        {
          "type": "createRedactions",
          "strategy": "text",
          "strategyOptions": {
            "text": "ACME Bank"
          }
        },
        {
          "type": "applyRedactions"
        }
      ]
    }
  ]
}' \
  -o result.pdf

POST /api/build HTTP/1.1
Content-Type: multipart/form-data; boundary=customboundary
Authorization: Token token=<API token>

--customboundary
Content-Disposition: form-data; name="file"; filename="example-document.pdf"
Content-Type: application/pdf

<PDF data>
--customboundary
Content-Disposition: form-data; name="instructions"
Content-Type: application/json

{
  "parts": [
    {
      "file": "document",
      "actions": [
        {
          "type": "createRedactions",
          "strategy": "text",
          "strategyOptions": {
            "text": "ACME Bank"
          }
        },
        {
          "type": "applyRedactions"
        }
      ]
    }
  ]
}
--customboundary--

This creates redaction annotations and applies them to the file, removing the content beneath them.

Creating and Applying Redactions in a File from a URL

Send a request to the /api/build endpoint and include a URL pointing to the file you want to redact:

curl -X POST http://localhost:5000/api/build \
  -H "Authorization: Token token=<API token>" \
  -F instructions='{
  "parts": [
    {
      "file": {
        "url": "https://pspdfkit.com/downloads/examples/credit-card-application.pdf"
      },
      "actions": [
        {
          "type": "createRedactions",
          "strategy": "text",
          "strategyOptions": {
            "text": "ACME Bank"
          }
        },
        {
          "type": "applyRedactions"
        }
      ]
    }
  ]
}' \
  -o result.pdf

POST /api/build HTTP/1.1
Content-Type: multipart/form-data; boundary=customboundary
Authorization: Token token=<API token>

--customboundary
Content-Disposition: form-data; name="instructions"
Content-Type: application/json

{
  "parts": [
    {
      "file": {
        "url": "https://pspdfkit.com/downloads/examples/credit-card-application.pdf"
      },
      "actions": [
        {
          "type": "createRedactions",
          "strategy": "text",
          "strategyOptions": {
            "text": "ACME Bank"
          }
        },
        {
          "type": "applyRedactions"
        }
      ]
    }
  ]
}
--customboundary--

This creates redaction annotations and applies them to the file, removing the content beneath them.