@onefootprint/footprint-expo-camera-module

Expo SDK bridge that exposes the native document capture screen from @onefootprint/footprint-native-camera-module to React Native code. Pairs with @onefootprint/footprint-expo (the SDK that handles the rest of the onboarding flow + the upload).

What this package does

• Provides a single async function: captureDocument({ documentSide, appearance, l10n, ... }).
• Presents the native capture screen modally on iOS (SwiftUI via UIHostingController) and as an Activity on Android (Compose via ActivityResultContract).
• Returns the captured image as a base64 JPEG. The SDK calls footprintQueries.uploadDoc(...) afterwards.

What this package does NOT do

• It does not own the UI — that lives in footprint-native-camera-module. This package is a ~150-line bridge that translates JS calls to native calls.
• It does not handle uploads. The SDK takes the returned image and uploads via the existing footprintQueries client.
• It does not duplicate detection or camera primitives. Both come from the native camera module.

Usage

import { captureDocument } from '@onefootprint/footprint-expo-camera-module';

const result = await captureDocument({
  documentSide: 'front',
  appearance: {
    theme: 'light',
    variables: {
      colorAccent: '#0052FF',
      buttonPrimaryBg: '#0052FF',
      buttonBorderRadius: '12px',
    },
  },
  l10n: { language: 'en' },
});

// result: { imageBase64, documentSide, capturedManually, fromGallery }
// then: await footprintQueries.uploadDoc({ ... })

Appearance and L10n mirror the shapes used by the rest of the Footprint SDKs (footprint-js, footprint-swift, footprint_flutter) — integrators can pass the same object they pass elsewhere.

Config plugin

Adds the iOS camera + photo-library usage descriptions to Info.plist, and the camera + photo permissions to AndroidManifest.xml. Wire it in app.json:

{
  "expo": {
    "plugins": [
      [
        "@onefootprint/footprint-expo-camera-module",
        {
          "cameraPermission": "Take a photo of your ID",
          "photoLibraryPermission": "Pick an ID photo from your library"
        }
      ]
    ]
  }
}

Dev workflow

Both this bridge and the native camera module are linked via yalc during local dev. To make a code change:

# 1. If you changed Kotlin / Swift in the native camera module:
cd ../footprint-native-camera-module
pnpm build:native             # rebuilds xcframework + AAR
yalc publish

# 2. Build this bridge:
cd ../footprint-expo-camera-module
yalc update                    # pulls the camera module update (if step 1 ran)
pnpm build                     # compiles TS + the config plugin
yalc publish

# 3. In the consuming app (e.g. demo-expo):
yalc update                    # pulls both bridges
pnpm install
npx expo prebuild --clean      # regenerates native projects + autolinks
npx expo run:ios               # (or run:android)

Or run pnpm dev:local from this directory to watch + auto-yalc-publish on every change.

Package layout

src/                           # TypeScript: captureDocument + types
ios/
├── FootprintExpoCameraModule.podspec     # depends on FootprintNativeCameraSwift (from the native module)
├── FootprintExpoCameraModule.swift       # Expo Module — presents the SwiftUI screen
└── CaptureDocumentOptionsRecord.swift    # Records for JS interop
android/
├── build.gradle                          # depends on the native camera module's android/ subproject
└── src/main/java/.../
    ├── FootprintExpoCameraModule.kt      # Expo Module — launches the Activity via the contract
    └── CaptureDocumentOptionsRecord.kt
plugin/src/                    # Expo config plugin (permissions injection)

Nothing UI-shaped lives here. The screen, overlays, capture pipeline, and translations all live in footprint-native-camera-module.

Publishing to npm

Published as @onefootprint/footprint-expo-camera-module via the mobile_npm_publish GitHub workflow (npm OIDC trusted publishing). prepack runs pnpm build, so build/ + plugin/build/ are freshly compiled into the tarball. Publish this bridge after the native camera module, and keep its @onefootprint/footprint-native-camera-module peer range in sync with that module's version.