integrate-file-viewer

---

name: integrate-file-viewer description: "MUST be used whenever integrating CogniteFileViewer into a Flows app to preview CDF files (PDFs, images, text). Do NOT manually wire up react-pdf or file resolution — this skill handles installation, Vite config, worker setup, and component usage. Triggers: file viewer, file preview, CogniteFileViewer, PDF viewer, view CDF files, document viewer, preview file." allowed-tools: Read, Glob, Grep, Edit, Write, Bash

Integrate CogniteFileViewer

Add CogniteFileViewer to this Flows app to preview CDF files (PDF, image, text).

Dependencies

The file-viewer library files (copied in Step 2) require this npm package:

Package	Version
react-pdf	^9.1.1

pdfjs-dist ships as a dependency of react-pdf at the correct version — do not install it separately. react and @cognite/sdk are assumed to already be present in Flows apps.

---

Your job

Complete these steps in order. Read each file before modifying it.

---

Step 1 — Understand the app

Read these files before touching anything:

• package.json — detect package manager (packageManager field or lock file) and existing deps
• vite.config.ts — understand current Vite setup
• The component where the viewer should be added

---

Step 2 — Copy the file-viewer source files

The file-viewer library lives in the code/ directory next to this skill file. Read and copy all files from there into src/cognite-file-viewer/ inside the app:

• code/types.ts
• code/mimeTypes.ts
• code/fileResolution.ts
• code/useViewport.ts
• code/useFileResolver.ts
• code/useDocumentAnnotations.ts
• code/DocumentAnnotationOverlay.tsx
• code/CogniteFileViewer.tsx
• code/index.ts

The PDF.js worker is configured inside CogniteFileViewer.tsx — no separate consumer setup is needed.

---

Step 3 — Install dependencies

Install react-pdf (see Dependencies above) using the app's package manager:

• pnpm → pnpm add react-pdf@^9.1.1
• npm → npm install react-pdf@^9.1.1
• yarn → yarn add react-pdf@^9.1.1

pnpm users: pnpm's strict linking may prevent the browser from resolving pdfjs-dist. Either add pdfjs-dist as a direct dependency (pnpm add pdfjs-dist), or add public-hoist-pattern[]=pdfjs-dist to .npmrc.

---

Step 4 — Configure Vite

Add optimizeDeps.exclude: ['pdfjs-dist'] to vite.config.ts to prevent Vite from pre-bundling pdfjs-dist (which breaks the worker):

export default defineConfig({
  // ... existing config ...
  optimizeDeps: {
    exclude: ['pdfjs-dist'],
  },
});

---

Step 5 — Use the component

Import and render CogniteFileViewer from the locally copied files:

import { CogniteFileViewer } from './cognite-file-viewer';

Get the sdk from the useDune() hook (already available in every Flows app):

import { useDune } from '@cognite/dune';
const { sdk } = useDune();

Supported file types

Type	Formats
PDF	.pdf — page navigation, zoom, pan, diagram annotation overlay
Office documents	Word, PowerPoint, Excel, ODS, ODP, ODT, RTF, TSV — converted to PDF via the CDF Document Preview API, then rendered identically to PDF
Image	JPEG, PNG, WebP, SVG, TIFF — zoom, pan, rotation
Text	.txt, .csv, .json — rendered as preformatted text
Other	Falls back to renderUnsupported

Minimal usage

This is all you need — zoom, pan, and touch gestures are handled internally:

<CogniteFileViewer
  source={{ type: 'internalId', id: file.id }}
  client={sdk}
  style={{ width: '100%', height: '600px' }}
/>

The component needs a defined height. If the parent has no explicit height, the viewer will collapse to zero. Always set a height via style, className, or the parent container.

File source

Pass any of three source types:

// By instance ID (data-modelled file — enables annotations)
<CogniteFileViewer
  source={{ type: 'instanceId', space: 'my-space', externalId: 'my-file' }}
  client={sdk}
/>

// By CDF internal ID
<CogniteFileViewer
  source={{ type: 'internalId', id: 12345 }}
  client={sdk}
/>

// By direct URL
<CogniteFileViewer
  source={{ type: 'url', url: 'https://...', mimeType: 'application/pdf' }}
/>

Prefer instanceId when available — it's the only source type that enables the diagram annotation overlay. When listing files via sdk.files.list(), check file.instanceId first:

source={
  file.instanceId
    ? { type: 'instanceId', space: file.instanceId.space, externalId: file.instanceId.externalId }
    : { type: 'internalId', id: file.id }
}

Full props reference

<CogniteFileViewer
  // Required
  source={source}
  client={sdk}              // required for instanceId and internalId sources

  // PDF pagination
  page={page}               // controlled current page (1-indexed)
  onPageChange={setPage}
  onDocumentLoad={({ numPages }) => setNumPages(numPages)}

  // Zoom & pan (works on PDF and images)
  zoom={zoom}               // 1 = 100%; Ctrl/Cmd+wheel, pinch-to-zoom, and middle-click drag built in
  onZoomChange={setZoom}
  minZoom={0.25}            // default
  maxZoom={5}               // default
  panOffset={pan}           // controlled pan offset; resets on page change
  onPanChange={setPan}

  // Fit mode
  fitMode="width"           // 'width' fits to container width; 'page' fits entire page in container

  // Rotation (PDFs and images)
  rotation={rotation}       // 0 | 90 | 180 | 270

  // Diagram annotations (instanceId sources only)
  showAnnotations={true}    // default
  onAnnotationClick={(annotation) => { /* annotation.linkedResource has space + externalId */ }}
  onAnnotationHover={(annotation) => {}}

  // Custom annotation tooltip (replaces native <title> tooltip)
  renderAnnotationTooltip={(annotation, rect) => (
    <div style={{
      position: 'absolute',
      left: rect.x + rect.width,
      top: rect.y,
      zIndex: 11,
    }}>
      {annotation.text}
    </div>
  )}

  // Custom overlay (SVG paths, highlights, drawings — works on PDF and images)
  renderOverlay={({ width, height, originalWidth, originalHeight, pageNumber, rotation }) => (
    <svg
      width={width}
      height={height}
      viewBox={`0 0 ${originalWidth} ${originalHeight}`}
      preserveAspectRatio="none"
      style={{ position: 'absolute', top: 0, left: 0, pointerEvents: 'all' }}
    >
      <path d="..." stroke="cyan" fill="none" />
    </svg>
  )}

  // Custom renderers (all optional)
  renderLoading={() => <MySpinner />}
  renderError={(error) => <MyError message={error.message} />}
  renderUnsupported={(mimeType) => <div>Cannot preview {mimeType}</div>}

  // Layout
  className="..."
  style={{ width: '100%', height: '100%' }}
/>

---

Tips & tricks

Reset page, zoom and rotation when the source changes. The component does not reset these automatically when you switch files — do it yourself:

const navigateToFile = (file: FileInfo) => {
  setSelectedFile(file);
  setPage(1);
  setZoom(1);
  setRotation(0);
};

Gate pagination UI on numPages > 0. onDocumentLoad only fires for PDFs. Don't render pagination controls until you know there are pages to paginate:

{numPages > 0 && (
  <>
    <button disabled={page <= 1} onClick={() => setPage(p => p - 1)}>‹</button>
    <span>{page} / {numPages}</span>
    <button disabled={page >= numPages} onClick={() => setPage(p => p + 1)}>›</button>
  </>
)}

Annotation click → navigate to linked file. annotation.linkedResource contains the space and externalId of the linked CDF instance. Match it against file.instanceId to navigate:

onAnnotationClick={(annotation) => {
  if (!annotation.linkedResource) return;
  const { space, externalId } = annotation.linkedResource;
  const linked = files.find(
    f => f.instanceId?.space === space && f.instanceId?.externalId === externalId
  );
  if (linked) navigateToFile(linked);
}}

Touch support is built in. Two-finger pinch-to-zoom and two-finger drag-to-pan work on touch devices automatically. No configuration needed.

Pan is middle-click drag (when zoomed in) on desktop. Left-click remains free for annotation clicks and text selection.

Ctrl/Cmd + wheel zooms toward the cursor — also built in. Wire zoom/onZoomChange if you want programmatic zoom buttons or to persist zoom state; otherwise it works fully uncontrolled.

renderOverlay receives original page dimensions (originalWidth, originalHeight) so you can set up an SVG viewBox in the original coordinate space. Paths drawn in PDF-point or image-pixel coordinates will map correctly to the rendered page at any zoom level.

---

Common pitfalls

Problem	Cause	Fix
Failed to resolve module specifier 'pdf.worker.mjs'	pdfjs-dist not hoisted (pnpm)	Add public-hoist-pattern[]=pdfjs-dist to .npmrc, or pnpm add pdfjs-dist directly
API version does not match Worker version	pdfjs-dist version mismatch between app and react-pdf	Do not install pdfjs-dist separately — let react-pdf provide it. If already installed, remove it
Annotations never show	instanceId is undefined — annotation overlay is disabled without it	Use instanceId source, or fall back and accept no annotations for classic files
Annotations show but are empty	File has no CogniteDiagramAnnotation edges in CDF	Expected — only P&ID/diagram files synced to the data model have annotations
Viewer collapses to zero height	Parent has no explicit height	Set height via style, className, or parent CSS