--- title: "Search and redact PDF server-side | Nutrient SDK" canonical_url: "https://www.nutrient.io/guides/document-engine/redaction/search-and-redact/" md_url: "https://www.nutrient.io/guides/document-engine/redaction/search-and-redact.md" last_updated: "2026-06-11T00:00:00.000Z" description: "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." --- # 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](https://www.nutrient.io/api/reference/document-engine/upstream/#model/BuildInstructions) with a `text` strategy. To learn more about redaction strategies, go to the [API reference](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Build-API/#create-redactions). 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](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Build-API/#create-redactions). The following example redacts any occurrence of the phrase ACME Bank: ```json { type: "createRedactions", strategy: "text", strategyOptions: { text: "ACME Bank" } } ``` ## Matching wrapped text with `word_based` Use the `word_based` strategy when the text you want to redact may wrap across line breaks, tables, or columns. This strategy ignores whitespace between characters — including spaces, tabs, newlines, and Unicode space variants — but punctuation must still match exactly. Queries must be at least three characters long. For example, a query for `Smith, John` matches `Smith,\nJohn`, but it won’t match `Smith John` because the comma is missing in the document text: ```json { type: "createRedactions", strategy: "word_based", strategyOptions: { word_based: "Smith, John" } } ``` ### 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](https://www.nutrient.io/api/reference/document-engine/upstream/#model/BuildInstructions) to the `/build` [instructions](https://www.nutrient.io/api/reference/document-engine/upstream/#model/BuildInstructions). - Ensure [Document Engine is up and running](https://www.nutrient.io/sdk/document-engine/getting-started.md). - Send a [multipart POST request](https://www.baeldung.com/postman-form-data-raw-x-www-form-urlencoded) with [instructions](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Build-API) to Document Engine’s `/api/build` endpoint. For more information, refer to the [API reference](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Build-API) to learn about the `/api/build` endpoint and all the actions you can perform on PDFs with Document Engine. For an overview of multipart requests, refer to the [brief tour of multipart requests](https://www.nutrient.io/blog/a-brief-tour-of-multipart-requests/) blog post. ## Creating and Applying Redactions in a File on Disk Send a multipart request to the [`/api/build` endpoint](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Document-Editing/operation/build-document) attached with the input file and the [`instructions` JSON](https://www.nutrient.io/api/reference/document-engine/upstream/#model/BuildInstructions): ### SHELL ```shell curl -X POST http://localhost:5000/api/build \ -H "Authorization: Token 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 ``` ### HTTP ```http POST /api/build HTTP/1.1 Content-Type: multipart/form-data; boundary=customboundary Authorization: Token token= --customboundary Content-Disposition: form-data; name="file"; filename="example-document.pdf" Content-Type: application/pdf --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](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Document-Editing/operation/build-document) and include a URL pointing to the file you want to redact: ### SHELL ```shell curl -X POST http://localhost:5000/api/build \ -H "Authorization: Token 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 ``` ### HTTP ```http POST /api/build HTTP/1.1 Content-Type: multipart/form-data; boundary=customboundary Authorization: Token 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. --- ## Related pages - [PDF Redaction Server](/guides/document-engine/redaction.md) - [Introduction to PDF redaction](/guides/document-engine/redaction/introduction.md) - [Redact PDFs using RegEx](/guides/document-engine/redaction/regex-patterns.md) - [Preset pattern redaction](/guides/document-engine/redaction/preset-patterns.md)