[APT-9577] Add DRM for downloads for offline usage : when remove a do…

…wnloaded audio, release and remove the downloaded license and its download info
scribd · Feb 12, 2024 · 114ee3b · 114ee3b
1 parent 60fe940
commit 114ee3b
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Showing 4 changed files with 63 additions and 2 deletions.
diff --git a/Armadillo/src/main/java/com/scribd/armadillo/download/DownloadEngine.kt b/Armadillo/src/main/java/com/scribd/armadillo/download/DownloadEngine.kt
@@ -76,9 +76,15 @@ internal class ExoplayerDownloadEngine @Inject constructor(
         })
     }
 
-    override fun removeDownload(audiobook: AudioPlayable) = downloadManager.removeDownload(audiobook.request.url)
+    override fun removeDownload(audiobook: AudioPlayable) {
+        downloadManager.removeDownload(audiobook.request.url)
+        offlineDrmManager.removeDownloadedDrmLicense(audiobook)
+    }
 
-    override fun removeAllDownloads() = downloadManager.removeAllDownloads()
+    override fun removeAllDownloads() {
+        downloadManager.removeAllDownloads()
+        offlineDrmManager.removeAllDownloadedDrmLicenses()
+    }
 
     override fun updateProgress() = downloadTracker.updateProgress()
 

diff --git a/Armadillo/src/main/java/com/scribd/armadillo/download/drm/DashDrmLicenseDownloader.kt b/Armadillo/src/main/java/com/scribd/armadillo/download/drm/DashDrmLicenseDownloader.kt
@@ -55,6 +55,18 @@ internal class DashDrmLicenseDownloader @Inject constructor(context: Context) :
         }
     }
 
+    override suspend fun releaseDrmLicense(drmDownload: DrmDownload) {
+        val offlineHelper = when (drmDownload.drmType) {
+            DrmType.WIDEVINE -> OfflineLicenseHelper.newWidevineInstance(drmDownload.licenseServer, drmDataSourceFactory, drmEventDispatcher)
+        }
+        try {
+            offlineHelper.releaseLicense(drmDownload.drmKeyId)
+        } catch (e: Exception) {
+            Log.e(DrmLicenseDownloader.TAG, "Failure to release downloaded DRM license", e)
+            throw DrmDownloadException(e)
+        }
+    }
+
     private fun DefaultHttpDataSource.Factory.addCustomHeaders(customHeaders: Map<String, String>) {
         customHeaders.takeIf { it.isNotEmpty() }?.let { headers ->
             setDefaultRequestProperties(headers)

diff --git a/Armadillo/src/main/java/com/scribd/armadillo/download/drm/DrmLicenseDownloader.kt b/Armadillo/src/main/java/com/scribd/armadillo/download/drm/DrmLicenseDownloader.kt
@@ -21,4 +21,9 @@ internal interface DrmLicenseDownloader {
         customRequestHeaders: Map<String, String>,
         drmInfo: DrmInfo,
     ): DrmDownload
+
+    /**
+     * Release a downloaded DRM license so it's no longer valid for usage.
+     */
+    suspend fun releaseDrmLicense(drmDownload: DrmDownload)
 }
diff --git a/Armadillo/src/main/java/com/scribd/armadillo/download/drm/OfflineDrmManager.kt b/Armadillo/src/main/java/com/scribd/armadillo/download/drm/OfflineDrmManager.kt
@@ -12,6 +12,7 @@ import com.scribd.armadillo.models.AudioPlayable
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.supervisorScope
 import javax.inject.Inject
 import javax.inject.Named
 import javax.inject.Singleton
@@ -48,4 +49,41 @@ internal class OfflineDrmManager @Inject constructor(
             }
         }
     }
+
+    fun removeDownloadedDrmLicense(audiobook: AudioPlayable) {
+        globalScope.launch(Dispatchers.IO) {
+            audiobook.request.drmInfo?.let { drmInfo ->
+                secureStorage.getDrmDownload(context, audiobook.request.url, drmInfo.drmType)?.let { drmDownload ->
+                    // Remove the persisted download info immediately so audio playback would stop using the offline license
+                    secureStorage.removeDrmDownload(context, audiobook.request.url, drmInfo.drmType)
+
+                    // Release the DRM license
+                    when (val type = drmDownload.audioType) {
+                        C.TYPE_DASH -> dashDrmLicenseDownloader
+                        else -> throw DrmContentTypeUnsupportedException(type)
+                    }.releaseDrmLicense(drmDownload)
+                }
+            }
+        }
+    }
+
+    fun removeAllDownloadedDrmLicenses() {
+        globalScope.launch(Dispatchers.IO) {
+            // Make sure that a removal fails, it won't affect the removal of other licenses
+            supervisorScope {
+                secureStorage.getAllDrmDownloads(context).forEach { drmDownloadPair ->
+                    launch {
+                        // Remove the persisted download info immediately so audio playback would stop using the offline license
+                        secureStorage.removeDrmDownload(context, drmDownloadPair.key)
+
+                        // Release the DRM license
+                        when (val type = drmDownloadPair.value.audioType) {
+                            C.TYPE_DASH -> dashDrmLicenseDownloader
+                            else -> throw DrmContentTypeUnsupportedException(type)
+                        }.releaseDrmLicense(drmDownloadPair.value)
+                    }
+                }
+            }
+        }
+    }
 }