Extract code to retrieve .well-known files to its own modules.

libraries/wellknown/impl/src/main/kotlin/io/element/android/libraries/wellknown/impl/DefaultWellknownRetriever.kt

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+/*
+ * Copyright 2025 New Vector 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.wellknown.impl
+
+import com.squareup.anvil.annotations.ContributesBinding
+import io.element.android.libraries.core.uri.ensureProtocol
+import io.element.android.libraries.di.AppScope
+import io.element.android.libraries.network.RetrofitFactory
+import io.element.android.libraries.wellknown.api.ElementWellKnown
+import io.element.android.libraries.wellknown.api.WellKnown
+import io.element.android.libraries.wellknown.api.WellKnownBaseConfig
+import io.element.android.libraries.wellknown.api.WellknownRetriever
+import timber.log.Timber
+import javax.inject.Inject
+
+@ContributesBinding(AppScope::class)
+class DefaultWellknownRetriever @Inject constructor(
+    private val retrofitFactory: RetrofitFactory,
+) : WellknownRetriever {
+    override suspend fun getWellKnown(baseUrl: String): WellKnown? {
+        val wellknownApi = buildWellknownApi(baseUrl) ?: return null
+        return try {
+            wellknownApi.getWellKnown().map()
+        } catch (e: Exception) {
+            Timber.e(e, "Failed to retrieve well-known data for $baseUrl")
+            null
+        }
+    }
+
+    override suspend fun getElementWellKnown(baseUrl: String): ElementWellKnown? {
+        val wellknownApi = buildWellknownApi(baseUrl) ?: return null
+        return try {
+            wellknownApi.getElementWellKnown().map()
+        } catch (e: Exception) {
+            Timber.e(e, "Failed to retrieve Element well-known data for $baseUrl")
+            null
+        }
+    }
+
+    private fun buildWellknownApi(accountProviderUrl: String): WellknownAPI? {
+        return try {
+            retrofitFactory.create(accountProviderUrl.ensureProtocol())
+                .create(WellknownAPI::class.java)
+        } catch (e: Exception) {
+            // If the base URL is not valid, we cannot retrieve the well-known data
+            Timber.e(e, "Failed to create Retrofit instance for $accountProviderUrl")
+            null
+        }
+    }
+}
+
+private fun InternalElementWellKnown.map() = ElementWellKnown(
+    registrationHelperUrl = registrationHelperUrl,
+    enforceElementPro = enforceElementPro,
+)
+
+private fun InternalWellKnown.map() = WellKnown(
+    homeServer = homeServer?.map(),
+    identityServer = identityServer?.map(),
+)
+
+private fun InternalWellKnownBaseConfig.map() = WellKnownBaseConfig(
+    baseURL = baseURL,
+)

libraries/wellknown/impl/src/main/kotlin/io/element/android/libraries/wellknown/impl/InternalElementWellKnown.kt

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+/*
+ * Copyright 2025 New Vector 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.wellknown.impl
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * Example:
+ * <pre>
+ * {
+ *     "registration_helper_url": "https://element.io"
+ * }
+ * </pre>
+ * .
+ */
+@Serializable
+data class InternalElementWellKnown(
+    @SerialName("registration_helper_url")
+    val registrationHelperUrl: String? = null,
+    @SerialName("enforce_element_pro")
+    val enforceElementPro: Boolean? = null,
+)

libraries/wellknown/impl/src/main/kotlin/io/element/android/libraries/wellknown/impl/InternalWellKnown.kt

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+/*
+ * Copyright 2023, 2024 New Vector 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.wellknown.impl
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * https://matrix.org/docs/spec/client_server/r0.4.0.html#server-discovery
+ * <pre>
+ * {
+ *     "m.homeserver": {
+ *         "base_url": "https://matrix.org"
+ *     },
+ *     "m.identity_server": {
+ *         "base_url": "https://vector.im"
+ *     },
+ * }
+ * </pre>
+ * .
+ */
+@Serializable
+data class InternalWellKnown(
+    @SerialName("m.homeserver")
+    val homeServer: InternalWellKnownBaseConfig? = null,
+    @SerialName("m.identity_server")
+    val identityServer: InternalWellKnownBaseConfig? = null,
+)

libraries/wellknown/impl/src/main/kotlin/io/element/android/libraries/wellknown/impl/InternalWellKnownBaseConfig.kt

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+/*
+ * Copyright 2023, 2024 New Vector 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.wellknown.impl
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * https://matrix.org/docs/spec/client_server/r0.4.0.html#server-discovery
+ * <pre>
+ * {
+ *     "base_url": "https://element.io"
+ * }
+ * </pre>
+ * .
+ */
+@Serializable
+data class InternalWellKnownBaseConfig(
+    @SerialName("base_url")
+    val baseURL: String? = null
+)

libraries/wellknown/impl/src/main/kotlin/io/element/android/libraries/wellknown/impl/WellknownAPI.kt

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+/*
+ * Copyright 2023, 2024 New Vector 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.wellknown.impl
+
+import retrofit2.http.GET
+
+internal interface WellknownAPI {
+    @GET(".well-known/matrix/client")
+    suspend fun getWellKnown(): InternalWellKnown
+
+    @GET(".well-known/element/element.json")
+    suspend fun getElementWellKnown(): InternalElementWellKnown
+}