whep-castlabs

castLabs DRM Subscriber (whep-castlabs)

This example extends a standard WHEPClient subscribe flow with castLabs DRMtoday integration to compare encrypted baseline playback and DRM-decrypted playback.

It is the subscriber-side pair for whip-castlabs.

What This Example Demonstrates

• dual subscriber paths in one page:
  • baseline subscriber (expected encrypted/garbled playback)
  • DRM subscriber (castLabs/decrypted playback path)
• applying CastLabs subscriber settings to DRM configuration
• wiring peer ontrack handling through castLabs transform APIs
• start/stop lifecycle for DRM subscriber while baseline can run continuously

CastLabs Subscriber Settings

The subscriber form includes:

• environment: DRMtoday environment where your encrypted stream configuration resides.
• merchant: DRMtoday merchant account.
• encryption mode / scheme setting: encryption profile associated with the stream.
• decrypt mode: ClearKey or Production DRM flow.
• key id / iv: values supplied by your merchant.

Notes:

• current key material handling in this example expects hex input values.
• form values are persisted and auto-restored with local storage helpers.

Subscriber Flow in This Example

Baseline Subscriber

• starts automatically on page load
• standard WHEP path without DRM transform
• useful for validating that encrypted content is not directly viewable

DRM Subscriber

On DRM subscribe start, the example:

1. reads/saves CastLabs settings
2. builds DRM config (environment, merchant, encryption/decrypt mode, keyId/iv)
3. runs rtcDrmConfigure(...)
4. creates WHEP subscriber with insertable streams enabled
5. routes peer ontrack to rtcDrmOnTrack(...) for decrypted playback

Minimal Developer Snippet

import { rtcDrmConfigure } from '@public/libs/castlabs/rtc-drm-transform/rtc-drm-transform.min.js'

await rtcDrmConfigure(drmConfig)

const subscriber = new red5prosdk.WHEPClient()
await subscriber.init({
  endpoint,
  streamName,
  connectionParams,
  rtcConfiguration: {
    ...rtcConfiguration,
    encodedInsertableStreams: true,
  },
})

subscriber.on('*', (event) => {
  if (event.type === 'WebRTC.PeerConnection.Available') {
    const pc = subscriber.getPeerConnection()
    pc.ontrack = (e) => {
      rtcDrmOnTrack(e, drmConfig)
    }
  }
})

await subscriber.subscribe()

Browser Requirements

This example requires modern browser support for:

• Web Workers
• Insertable Streams
• TransformStream

Polyfills are included in the example page for track processor/generator APIs where needed.

DRMtoday Context

This README does not attempt to document DRMtoday platform configuration. Use castLabs DRMtoday documentation for environment, merchant, and key provisioning details.

Endpoint and connectionParams: Standalone vs Stream Manager

CastLabs subscriber behavior is independent from deployment mode. Endpoint and connection setup follows the same WHEP pattern as other examples.

Standalone Server

const endpoint = `https://${host}:443/live/whep/${streamName}`
const connectionParams = {}

Stream Manager

const endpoint = `https://${host}/as/v1/proxy/whep/${app}/${streamName}`
const connectionParams = {
  // e.g. region, nodeGroup, auth metadata
}

Where to Look in This Example

• baseline subscriber startup: startBaselineSubscribe()
• DRM subscriber startup: startDrmSubscribe()
• castLabs form read/save: readCastLabsSubForm() / saveCastLabsSubSettings()
• DRM config + configure call: rtcDrmConfigure(...)
• decrypted playback hook: rtcDrmOnTrack(...)
• shared subscriber factory: createSubscriber()

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Pair this with whip-castlabs for the sender-side encryption worker/transform setup.