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Custom LCP client (iOS)

When readium_lcp_pods links liblcp, this package adapts and registers it for you. Register your own client instead when:

  • your app adds R2LCPClient some other way (Swift Package Manager, Carthage, or a framework added in Xcode), since this package's pod can't see it then; or
  • you want a different LCPClient, such as a test client.

A registered client always takes precedence over the one readium_lcp_pods links.

1. Declare the registry​

This package's Swift module can't be imported from an app (its Nitro headers are C++), so declare its registry in your bridging header:

MyApp-Bridging-Header.h
#import <Foundation/Foundation.h>

@interface RNRLCPClientRegistry : NSObject
+ (BOOL)registerClient:(id)client;
@end

2. Adapt R2LCPClient​

import R2LCPClient
import ReadiumLCP

final class LiblcpClient: ReadiumLCP.LCPClient {
  func createContext(jsonLicense: String, hashedPassphrase: LCPPassphraseHash, pemCrl: String) throws -> LCPClientContext {
    try R2LCPClient.createContext(jsonLicense: jsonLicense, hashedPassphrase: hashedPassphrase, pemCrl: pemCrl)
  }

  func decrypt(data: Data, using context: LCPClientContext) -> Data? {
    R2LCPClient.decrypt(data: data, using: context as! DRMContext)
  }

  func findOneValidPassphrase(jsonLicense: String, hashedPassphrases: [LCPPassphraseHash]) -> LCPPassphraseHash? {
    R2LCPClient.findOneValidPassphrase(jsonLicense: jsonLicense, hashedPassphrases: hashedPassphrases)
  }
}

3. Register it at launch​

In application(_:didFinishLaunchingWithOptions:), before JS calls LCP.initialize():

RNRLCPClientRegistry.registerClient(LiblcpClient())

registerClient returns false if the object isn't a ReadiumLCP.LCPClient.

On Android, Readium loads liblcp from the classpath, so there's nothing to register.