---
title: "Generate a session token"
canonical_url: "https://www.nutrient.io/guides/dws-viewer/developer-guides/generate-a-session-token/"
md_url: "https://www.nutrient.io/guides/dws-viewer/developer-guides/generate-a-session-token.md"
last_updated: "2026-05-27T14:30:58.374Z"
description: "Learn how to generate a session token for DWS Viewer API authentication using your API key and the POST /viewer/sessions endpoint."
---

# Generate a session token

Session tokens used for authentication by DWS Viewer API can be generated using your API key through the [`POST /viewer/sessions`](https://www.nutrient.io/api/reference/viewer/public/#tag/Authorization/operation/generate-session-token) endpoint:

```shell

curl -X POST https://api.nutrient.io/viewer/sessions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer pdf_live_m1aKhcLgvDBnKjK2X8UL8rhDxuChoGwDFnStimhDGBE" \
  --fail \
  -d '{
      "allowed_documents": [
        {
          "document_id": "<document_id>",
          "document_permissions": [
            "read",
            "write",
            "download"
          ]
        }
      ],
      "exp": 1793769299
    }'

```

```powershell

curl -X POST https://api.nutrient.io/viewer/sessions ^
  -H "Content-Type: application/json" ^
  -H "Authorization: Bearer pdf_live_m1aKhcLgvDBnKjK2X8UL8rhDxuChoGwDFnStimhDGBE" ^
  --fail ^
  -d "{\"allowed_documents\": [{\"document_id\": \"<document_id>\", \"document_permissions\": [\"read\", \"write\", \"download\"]}], \"exp\": 1793769299}"

```

```http

POST https://api.nutrient.io/viewer/sessions HTTP/1.1
Content-Type: application/json
Authorization: Bearer pdf_live_m1aKhcLgvDBnKjK2X8UL8rhDxuChoGwDFnStimhDGBE

{
  "allowed_documents": [
    {
      "document_id": "<document_id>",
      "document_permissions": [
        "read",
        "write",
        "download"
      ]
    }
  ],
  "exp": 1793769299
}

```

You can then retrieve the session token from the response:

```json

{
  "jwt": "<created_session_token>"
}

```

## Complete integration example

Below is a server-side implementation example showing how to generate a session token for a document:

```js

const express = require("express");

const app = express();
app.use(express.json());

// Generate session token for a document.
app.post("/api/create-session", async (req, res) => {
  try {
    const { documentId } = req.body;
    const apiKey = process.env.NUTRIENT_DWS_VIEWER_API_KEY;

    if (!documentId) {
      return res.status(400).json({
        success: false,
        error: "Document ID is required",
      });
    }

    // Generate session token.
    const sessionPayload = {
      allowed_documents: [
        {
          document_id: documentId,
          document_permissions: ["read", "write", "download"],
        },
      ],
      exp: Math.floor(Date.now() / 1000) + 60 * 60, // 1 hour from now
    };

    const sessionResponse = await fetch(
      "https://api.nutrient.io/viewer/sessions",
      {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
          Authorization: `Bearer ${apiKey}`,
        },
        body: JSON.stringify(sessionPayload),
      },
    );

    if (!sessionResponse.ok) {
      throw new Error(`Session creation failed: ${sessionResponse.statusText}`);
    }

    const sessionResult = await sessionResponse.json();

    res.json({
      success: true,
      sessionToken: sessionResult.jwt,
    });
  } catch (error) {
    console.error("Error:", error);
    res.status(500).json({
      success: false,
      error: error.message,
    });
  }
});

```

## Document permissions

When generating session tokens, you can configure the permissions for each document in the `document_permissions` array. This enables you to control what actions users can perform on the document.

For the complete list of available permissions and their descriptions, refer to the [API reference](https://www.nutrient.io/api/reference/viewer/public/).

## Session token expiration

Session tokens expire based on the `exp` claim, which uses Unix time format (seconds since 1970-01-01T00:00:00Z). By default, session tokens expire in 1 hour if no `exp` claim is specified.

## Next steps

To use session tokens with your documents:

1. **Upload documents** — First, [upload your documents](https://www.nutrient.io/guides/dws-viewer/developer-guides/upload-documents.md) to DWS to obtain document IDs.

2. **Open in Web SDK** — Use the session token to [open the document in Nutrient Web SDK](https://www.nutrient.io/guides/dws-viewer/developer-guides/open-a-document-in-web.md).

For a complete server implementation example, refer to the [Node.js integration example](https://www.nutrient.io/guides/dws-viewer/examples/nodejs-integration-example.md) guide.

> Session tokens can be created with additional optional claims to further control their properties. Refer to our [API reference](https://www.nutrient.io/api/reference/viewer/public/) for more information.
---

## Related pages

- [Architecture of DWS Viewer API integration](/guides/dws-viewer/developer-guides/architecture.md)
- [DWS Viewer API client authentication flow](/guides/dws-viewer/developer-guides/client-authentication-flow.md)
- [DWS Viewer API backend authentication](/guides/dws-viewer/developer-guides/backend-authentication.md)
- [Dashboard](/guides/dws-viewer/developer-guides/dashboard.md)
- [Deployment options](/guides/dws-viewer/developer-guides/deployment-options.md)
- [DWS Viewer API developer guides](/guides/dws-viewer/developer-guides.md)
- [Open a document in Web SDK](/guides/dws-viewer/developer-guides/open-a-document-in-web.md)
- [Upload documents](/guides/dws-viewer/developer-guides/upload-documents.md)
- [Integrate DWS Viewer API with your own backend](/guides/dws-viewer/developer-guides/use-with-your-backend.md)