Merge pull request #6035 from element-hq/fix/remove-fragment-part-in-mxc-urls

Add `MediaSource.safeUrl` for removing invalid fragment part from URLs

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/timeline/model/event/TimelineItemStickerContent.kt

@@ -30,5 +30,5 @@ data class TimelineItemStickerContent(
 
     /* Stickers are supposed to be small images so
        we allow using the mediaSource (unless the url is empty) */
-    val preferredMediaSource = if (mediaSource.url.isEmpty()) thumbnailSource else mediaSource
+    val preferredMediaSource = if (mediaSource.safeUrl.isEmpty()) thumbnailSource else mediaSource
 }

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/media/MediaSource.kt

@@ -9,6 +9,7 @@
 package io.element.android.libraries.matrix.api.media
 
 import android.os.Parcelable
+import kotlinx.parcelize.IgnoredOnParcel
 import kotlinx.parcelize.Parcelize
 
 @Parcelize
@@ -16,9 +17,20 @@ data class MediaSource(
     /**
      * Url of the media.
      */
-    val url: String,
+    private val url: String,
     /**
      * This is used to hold data for encrypted media.
      */
     val json: String? = null,
-) : Parcelable
+) : Parcelable {
+    /**
+     * A URL with invalid parts (like `#fragment`, if it's an MXC url) removed.
+     */
+    @IgnoredOnParcel
+    val safeUrl = if (url.startsWith("mxc")) {
+        // We've seen some MXC urls in the wild having some `mxc://foo/bar#auto` fragment suffix, which is invalid
+        url.substringBefore("#")
+    } else {
+        url
+    }
+}

libraries/matrix/api/src/test/kotlin/io/element/android/libraries/matrix/api/media/MediaSourceTest.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.matrix.api.media
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.matrix.test.media.aMediaSource
+import org.junit.Test
+
+class MediaSourceTest {
+    @Test
+    fun `safeUrl removes the fragment part in MXC urls`() {
+        val mediaSource = aMediaSource(url = "mxc://matrix.org/url#fragment")
+        assertThat(mediaSource.safeUrl).isEqualTo("mxc://matrix.org/url")
+    }
+
+    @Test
+    fun `safeUrl keeps the fragment part in a non-MXC url`() {
+        val mediaSource = aMediaSource(url = "https://matrix.org/url#fragment")
+        assertThat(mediaSource.safeUrl).isEqualTo("https://matrix.org/url#fragment")
+    }
+}

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/media/RustMediaLoader.kt

@@ -91,7 +91,7 @@ class RustMediaLoader(
         return if (json != null) {
             RustMediaSource.fromJson(json)
         } else {
-            RustMediaSource.fromUrl(url)
+            RustMediaSource.fromUrl(safeUrl)
         }
     }
 }

libraries/matrixmedia/impl/src/main/kotlin/io/element/android/libraries/matrix/ui/media/CoilMediaFetcher.kt

@@ -27,15 +27,15 @@ internal class CoilMediaFetcher(
     private val mediaData: MediaRequestData,
 ) : Fetcher {
     override suspend fun fetch(): FetchResult? {
-        val source = mediaData.source
-        if (source == null) {
+        val mediaSource = mediaData.source
+        if (mediaSource == null) {
             Timber.e("MediaData source is null")
             return null
         }
         return when (val kind = mediaData.kind) {
-            is MediaRequestData.Kind.Content -> fetchContent(source)
-            is MediaRequestData.Kind.Thumbnail -> fetchThumbnail(source, kind)
-            is MediaRequestData.Kind.File -> fetchFile(source, kind)
+            is MediaRequestData.Kind.Content -> fetchContent(mediaSource)
+            is MediaRequestData.Kind.Thumbnail -> fetchThumbnail(mediaSource, kind)
+            is MediaRequestData.Kind.File -> fetchFile(mediaSource, kind)
         }
     }
 

libraries/matrixmedia/impl/src/main/kotlin/io/element/android/libraries/matrix/ui/media/MediaRequestDataKeyer.kt

@@ -25,5 +25,5 @@ internal class MediaRequestDataKeyer : Keyer<MediaRequestData> {
 }
 
 private fun MediaRequestData.toKey(): String? {
-    return source?.let { "${it.url}_$kind" }
+    return source?.let { "${it.safeUrl}_$kind" }
 }

libraries/mediaviewer/impl/src/main/kotlin/io/element/android/libraries/mediaviewer/impl/viewer/MediaViewerDataSource.kt

@@ -126,7 +126,7 @@ class MediaViewerDataSource(
             when (mediaItem) {
                 is MediaItem.DateSeparator -> Unit
                 is MediaItem.Event -> {
-                    val sourceUrl = mediaItem.mediaSource().url
+                    val sourceUrl = mediaItem.mediaSource().safeUrl
                     val localMedia = localMediaStates.getOrPut(sourceUrl) {
                         mutableStateOf(AsyncData.Uninitialized)
                     }
@@ -153,7 +153,7 @@ class MediaViewerDataSource(
     }.toImmutableList()
 
     fun clearLoadingError(data: MediaViewerPageData.MediaViewerData) {
-        localMediaStates[data.mediaSource.url]?.value = AsyncData.Uninitialized
+        localMediaStates[data.mediaSource.safeUrl]?.value = AsyncData.Uninitialized
     }
 
     suspend fun loadMore(direction: Timeline.PaginationDirection) {
@@ -162,7 +162,7 @@ class MediaViewerDataSource(
 
     suspend fun loadMedia(data: MediaViewerPageData.MediaViewerData) {
         Timber.d("loadMedia for ${data.eventId}")
-        val localMediaState = localMediaStates.getOrPut(data.mediaSource.url) {
+        val localMediaState = localMediaStates.getOrPut(data.mediaSource.safeUrl) {
             mutableStateOf(AsyncData.Uninitialized)
         }
         localMediaState.value = AsyncData.Loading()

libraries/push/impl/src/main/kotlin/io/element/android/libraries/push/impl/notifications/NotificationMediaRepo.kt

@@ -101,7 +101,7 @@ class DefaultNotificationMediaRepo(
         }
     }
 
-    private fun MediaSource.cachedFile(): File? = mxcTools.mxcUri2FilePath(url)?.let {
+    private fun MediaSource.cachedFile(): File? = mxcTools.mxcUri2FilePath(safeUrl)?.let {
         File("${cacheDir.path}/$CACHE_NOTIFICATION_SUBDIR/$it")
     }
 }

libraries/voiceplayer/impl/src/main/kotlin/io/element/android/libraries/voiceplayer/impl/VoiceMessageMediaRepo.kt

@@ -95,7 +95,7 @@ class DefaultVoiceMessageMediaRepo(
         }
     }
 
-    private val cachedFile: File? = mxcTools.mxcUri2FilePath(mediaSource.url)?.let {
+    private val cachedFile: File? = mxcTools.mxcUri2FilePath(mediaSource.safeUrl)?.let {
         File("${cacheDir.path}/$CACHE_VOICE_SUBDIR/$it")
     }
 }