Fix ChatTheme crashing in Compose previews and VRT tests when ChatClient is not initialized (#6366)

Co-authored-by: Claude <noreply@anthropic.com>

Author: VelikovPetar

stream-chat-android-compose/src/main/java/io/getstream/chat/android/compose/ui/theme/ChatTheme.kt

@@ -308,9 +308,11 @@ private val LocalMediaGalleryConfig = compositionLocalOf<MediaGalleryConfig> {
  * @param durationFormatter [DurationFormatter] Used to format durations in the app.
  * @param channelNameFormatter [ChannelNameFormatter] Used throughout the app for channel names.
  * @param messagePreviewFormatter [MessagePreviewFormatter] Used to generate a string preview for the given message.
- * @param imageLoaderFactory A factory that creates new Coil [ImageLoader] instances. If used in combination with
- * [asyncImageHeadersProvider] you must override the [StreamCoilImageLoaderFactory.imageLoader] method accepting the
- * interceptors parameter.
+ * @param imageLoaderFactory A factory that creates new Coil [ImageLoader] instances. If you provide a custom factory
+ * **and** use a custom CDN (via [io.getstream.chat.android.client.ChatClient.Builder]) or
+ * [asyncImageHeadersProvider], you must override the [StreamCoilImageLoaderFactory.imageLoader] overload that accepts
+ * interceptors; otherwise those features are silently ignored. If you don't use either, overriding the single-arg
+ * method is sufficient.
  * @param imageAssetTransformer [ImageAssetTransformer] Used to transform image assets.
  * @param imageHeadersProvider [ImageHeadersProvider] Deprecated. Use [asyncImageHeadersProvider] instead. Headers
  * provided here are injected synchronously on the main thread, which blocks the UI for any non-trivial work.
@@ -458,17 +460,12 @@ public fun ChatTheme(
     }
 
     val context = LocalContext.current
-    val cdn = remember { ChatClient.instance().cdn }
-    val imageLoader = remember(imageLoaderFactory, asyncImageHeadersProvider, cdn) {
+    val imageLoader = remember(imageLoaderFactory, asyncImageHeadersProvider) {
         val interceptors = buildList {
             asyncImageHeadersProvider?.let { add(ImageHeadersInterceptor(it)) }
-            cdn?.let { add(CDNImageInterceptor(it)) }
-        }
-        if (interceptors.isEmpty()) {
-            imageLoaderFactory.imageLoader(context.applicationContext)
-        } else {
-            imageLoaderFactory.imageLoader(context.applicationContext, interceptors)
+            add(CDNImageInterceptor())
         }
+        imageLoaderFactory.imageLoader(context.applicationContext, interceptors)
     }
 
     @Suppress("DEPRECATION")

stream-chat-android-ui-common/src/main/kotlin/io/getstream/chat/android/ui/common/images/internal/CDNImageInterceptor.kt

@@ -19,6 +19,7 @@ package io.getstream.chat.android.ui.common.images.internal
 import coil3.intercept.Interceptor
 import coil3.network.httpHeaders
 import coil3.request.ImageResult
+import io.getstream.chat.android.client.ChatClient
 import io.getstream.chat.android.client.cdn.CDN
 import io.getstream.chat.android.core.internal.InternalStreamChatApi
 import io.getstream.log.taggedLogger
@@ -34,13 +35,21 @@ import kotlinx.coroutines.withContext
  * them for the same key.
  *
  * Only HTTP/HTTPS URLs are intercepted; local resources, content URIs, etc. pass through unchanged.
+ *
+ * The [CDN] instance is resolved lazily via [cdn] on each request, so the interceptor
+ * is safe to install even before [ChatClient] is initialized (e.g. Compose previews, VRT tests).
+ * When [cdn] returns `null` the request passes through unchanged.
  */
 @InternalStreamChatApi
-public class CDNImageInterceptor(private val cdn: CDN) : Interceptor {
+public class CDNImageInterceptor(
+    private val cdn: () -> CDN? = { if (ChatClient.isInitialized) ChatClient.instance().cdn else null },
+) : Interceptor {
 
     private val logger by taggedLogger("Chat:CDNImageInterceptor")
 
     override suspend fun intercept(chain: Interceptor.Chain): ImageResult {
+        val cdn = cdn() ?: return chain.proceed()
+
         val request = chain.request
         val url = request.data.toString()
 

stream-chat-android-ui-common/src/main/kotlin/io/getstream/chat/android/ui/common/images/internal/StreamCoil.kt

@@ -19,7 +19,6 @@ package io.getstream.chat.android.ui.common.images.internal
 import android.content.Context
 import coil3.ImageLoader
 import coil3.SingletonImageLoader
-import io.getstream.chat.android.client.ChatClient
 import io.getstream.chat.android.core.internal.InternalStreamChatApi
 import io.getstream.chat.android.ui.common.images.StreamImageLoaderFactory
 
@@ -48,10 +47,7 @@ public object StreamCoil {
     }
 
     private fun newImageLoaderFactory(): SingletonImageLoader.Factory {
-        val cdn = ChatClient.instance().cdn
-        val interceptors = buildList {
-            cdn?.let { add(CDNImageInterceptor(it)) }
-        }
+        val interceptors = listOf(CDNImageInterceptor())
         return StreamImageLoaderFactory(interceptors).apply {
             imageLoaderFactory = this
         }

stream-chat-android-ui-common/src/test/kotlin/io/getstream/chat/android/ui/common/images/internal/CDNImageInterceptorTest.kt

@@ -48,7 +48,7 @@ internal class CDNImageInterceptorTest {
             override suspend fun imageRequest(url: String) =
                 CDNRequest("https://cdn.example.com/image.jpg")
         }
-        val interceptor = CDNImageInterceptor(cdn)
+        val interceptor = CDNImageInterceptor { cdn }
         val request = ImageRequest.Builder(context)
             .data("https://original.com/image.jpg")
             .build()
@@ -66,7 +66,7 @@ internal class CDNImageInterceptorTest {
             override suspend fun imageRequest(url: String) =
                 CDNRequest(url, mapOf("Authorization" to "Bearer token", "X-Custom" to "value"))
         }
-        val interceptor = CDNImageInterceptor(cdn)
+        val interceptor = CDNImageInterceptor { cdn }
         val request = ImageRequest.Builder(context)
             .data("https://original.com/image.jpg")
             .build()
@@ -85,7 +85,7 @@ internal class CDNImageInterceptorTest {
             override suspend fun imageRequest(url: String) =
                 CDNRequest(url, mapOf("Authorization" to "CDN-token"))
         }
-        val interceptor = CDNImageInterceptor(cdn)
+        val interceptor = CDNImageInterceptor { cdn }
         val existingHeaders = NetworkHeaders.Builder()
             .add("Authorization", "Original-token")
             .add("X-Existing", "keep-me")
@@ -112,7 +112,7 @@ internal class CDNImageInterceptorTest {
                 return CDNRequest("https://should-not-be-used.com")
             }
         }
-        val interceptor = CDNImageInterceptor(cdn)
+        val interceptor = CDNImageInterceptor { cdn }
         val request = ImageRequest.Builder(context)
             .data("content://media/image.jpg")
             .build()
@@ -132,7 +132,7 @@ internal class CDNImageInterceptorTest {
                 throw RuntimeException("CDN unavailable")
             }
         }
-        val interceptor = CDNImageInterceptor(cdn)
+        val interceptor = CDNImageInterceptor { cdn }
         val request = ImageRequest.Builder(context)
             .data("https://original.com/image.jpg")
             .build()
@@ -143,6 +143,19 @@ internal class CDNImageInterceptorTest {
         assertTrue("Should fall back to direct proceed on CDN error", chain.directProceed)
     }
 
+    @Test
+    fun `intercept passes through when cdn returns null`() = runTest {
+        val interceptor = CDNImageInterceptor { null }
+        val request = ImageRequest.Builder(context)
+            .data("https://original.com/image.jpg")
+            .build()
+        val chain = FakeCoilChain(request)
+
+        interceptor.intercept(chain)
+
+        assertTrue("Should pass through when CDN is null", chain.directProceed)
+    }
+
     @Suppress("EmptyFunctionBlock")
     private class FakeCoilChain(
         override val request: ImageRequest,