OkHttp lazy initialization

app/src/main/kotlin/com/google/samples/apps/nowinandroid/NiaApplication.kt

@@ -23,15 +23,14 @@ import com.google.samples.apps.nowinandroid.sync.initializers.Sync
 import com.google.samples.apps.nowinandroid.util.ProfileVerifierLogger
 import dagger.hilt.android.HiltAndroidApp
 import javax.inject.Inject
-import javax.inject.Provider
 
 /**
  * [Application] class for NiA
  */
 @HiltAndroidApp
 class NiaApplication : Application(), ImageLoaderFactory {
     @Inject
-    lateinit var imageLoader: Provider<ImageLoader>
+    lateinit var imageLoader: dagger.Lazy<ImageLoader>
 
     @Inject
     lateinit var profileVerifierLogger: ProfileVerifierLogger

build-logic/convention/src/main/kotlin/AndroidFeatureConventionPlugin.kt

@@ -44,6 +44,8 @@ class AndroidFeatureConventionPlugin : Plugin<Project> {
                 add("implementation", libs.findLibrary("androidx.hilt.navigation.compose").get())
                 add("implementation", libs.findLibrary("androidx.lifecycle.runtimeCompose").get())
                 add("implementation", libs.findLibrary("androidx.lifecycle.viewModelCompose").get())
+
+                add("implementation", libs.findLibrary("androidx.tracing.ktx").get())
             }
         }
     }

build-logic/convention/src/main/kotlin/AndroidLibraryConventionPlugin.kt

@@ -21,6 +21,7 @@ import com.google.samples.apps.nowinandroid.configureGradleManagedDevices
 import com.google.samples.apps.nowinandroid.configureKotlinAndroid
 import com.google.samples.apps.nowinandroid.configurePrintApksTask
 import com.google.samples.apps.nowinandroid.disableUnnecessaryAndroidTests
+import com.google.samples.apps.nowinandroid.libs
 import org.gradle.api.Plugin
 import org.gradle.api.Project
 import org.gradle.kotlin.dsl.configure
@@ -51,6 +52,8 @@ class AndroidLibraryConventionPlugin : Plugin<Project> {
             }
             dependencies {
                 add("testImplementation", kotlin("test"))
+
+                add("implementation", libs.findLibrary("androidx.tracing.ktx").get())
             }
         }
     }

core/network/src/main/kotlin/com/google/samples/apps/nowinandroid/core/network/di/NetworkModule.kt

@@ -17,6 +17,7 @@
 package com.google.samples.apps.nowinandroid.core.network.di
 
 import android.content.Context
+import androidx.tracing.trace
 import coil.ImageLoader
 import coil.decode.SvgDecoder
 import coil.util.DebugLogger
@@ -51,16 +52,18 @@ internal object NetworkModule {
 
     @Provides
     @Singleton
-    fun okHttpCallFactory(): Call.Factory = OkHttpClient.Builder()
-        .addInterceptor(
-            HttpLoggingInterceptor()
-                .apply {
-                    if (BuildConfig.DEBUG) {
-                        setLevel(HttpLoggingInterceptor.Level.BODY)
-                    }
-                },
-        )
-        .build()
+    fun okHttpCallFactory(): Call.Factory = trace("NiaOkHttpClient") {
+        OkHttpClient.Builder()
+            .addInterceptor(
+                HttpLoggingInterceptor()
+                    .apply {
+                        if (BuildConfig.DEBUG) {
+                            setLevel(HttpLoggingInterceptor.Level.BODY)
+                        }
+                    },
+            )
+            .build()
+    }
 
     /**
      * Since we're displaying SVGs in the app, Coil needs an ImageLoader which supports this
@@ -72,20 +75,21 @@ internal object NetworkModule {
     @Provides
     @Singleton
     fun imageLoader(
-        okHttpCallFactory: Call.Factory,
+        // We specifically request dagger.Lazy here, so that it's not instantiated from Dagger.
+        okHttpCallFactory: dagger.Lazy<Call.Factory>,
         @ApplicationContext application: Context,
-    ): ImageLoader = ImageLoader.Builder(application)
-        .callFactory(okHttpCallFactory)
-        .components {
-            add(SvgDecoder.Factory())
-        }
-        // Assume most content images are versioned urls
-        // but some problematic images are fetching each time
-        .respectCacheHeaders(false)
-        .apply {
-            if (BuildConfig.DEBUG) {
-                logger(DebugLogger())
+    ): ImageLoader = trace("NiaImageLoader") {
+        ImageLoader.Builder(application)
+            .callFactory { okHttpCallFactory.get() }
+            .components { add(SvgDecoder.Factory()) }
+            // Assume most content images are versioned urls
+            // but some problematic images are fetching each time
+            .respectCacheHeaders(false)
+            .apply {
+                if (BuildConfig.DEBUG) {
+                    logger(DebugLogger())
+                }
             }
-        }
-        .build()
+            .build()
+    }
 }

core/network/src/main/kotlin/com/google/samples/apps/nowinandroid/core/network/retrofit/RetrofitNiaNetwork.kt

@@ -16,6 +16,7 @@
 
 package com.google.samples.apps.nowinandroid.core.network.retrofit
 
+import androidx.tracing.trace
 import com.google.samples.apps.nowinandroid.core.network.BuildConfig
 import com.google.samples.apps.nowinandroid.core.network.NiaNetworkDataSource
 import com.google.samples.apps.nowinandroid.core.network.model.NetworkChangeList
@@ -73,17 +74,21 @@ private data class NetworkResponse<T>(
 @Singleton
 internal class RetrofitNiaNetwork @Inject constructor(
     networkJson: Json,
-    okhttpCallFactory: Call.Factory,
+    okhttpCallFactory: dagger.Lazy<Call.Factory>,
 ) : NiaNetworkDataSource {
 
-    private val networkApi = Retrofit.Builder()
-        .baseUrl(NIA_BASE_URL)
-        .callFactory(okhttpCallFactory)
-        .addConverterFactory(
-            networkJson.asConverterFactory("application/json".toMediaType()),
-        )
-        .build()
-        .create(RetrofitNiaNetworkApi::class.java)
+    private val networkApi = trace("RetrofitNiaNetwork") {
+        Retrofit.Builder()
+            .baseUrl(NIA_BASE_URL)
+            // We use callFactory lambda here with dagger.Lazy<Call.Factory>
+            // to prevent initializing OkHttp on the main thread.
+            .callFactory { okhttpCallFactory.get().newCall(it) }
+            .addConverterFactory(
+                networkJson.asConverterFactory("application/json".toMediaType()),
+            )
+            .build()
+            .create(RetrofitNiaNetworkApi::class.java)
+    }
 
     override suspend fun getTopics(ids: List<String>?): List<NetworkTopic> =
         networkApi.getTopics(ids = ids).data

feature/foryou/src/main/kotlin/com/google/samples/apps/nowinandroid/feature/foryou/ForYouScreen.kt

@@ -81,7 +81,7 @@ import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.max
 import androidx.compose.ui.unit.sp
-import androidx.compose.ui.util.trace
+import androidx.tracing.trace
 import androidx.hilt.navigation.compose.hiltViewModel
 import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import com.google.accompanist.permissions.ExperimentalPermissionsApi

gradle/libs.versions.toml

@@ -24,7 +24,7 @@ androidxTestCore = "1.5.0"
 androidxTestExt = "1.1.5"
 androidxTestRules = "1.5.0"
 androidxTestRunner = "1.5.2"
-androidxTracing = "1.1.0"
+androidxTracing = "1.3.0-alpha02"
 androidxUiAutomator = "2.2.0"
 androidxWindowManager = "1.2.0"
 androidxWork = "2.9.0"