[ECO-4943] feat: basic sending and receiving messages in the Chat

.gitignore

@@ -95,6 +95,7 @@ publish.properties
 /.idea/compiler.xml
 /.idea/jarRepositories.xml
 /.idea/misc.xml
+/.idea/shelf
 
 # general
 **/.DS_Store

chat-android/src/main/java/com/ably/chat/ChatApi.kt

@@ -2,9 +2,6 @@ package com.ably.chat
 
 import com.google.gson.JsonElement
 import com.google.gson.JsonObject
-import com.google.gson.JsonPrimitive
-import io.ably.lib.http.HttpCore
-import io.ably.lib.http.HttpUtils
 import io.ably.lib.types.AblyException
 import io.ably.lib.types.AsyncHttpPaginatedResponse
 import io.ably.lib.types.ErrorInfo
@@ -17,19 +14,20 @@ private const val API_PROTOCOL_VERSION = 3
 private const val PROTOCOL_VERSION_PARAM_NAME = "v"
 private val apiProtocolParam = Param(PROTOCOL_VERSION_PARAM_NAME, API_PROTOCOL_VERSION.toString())
 
-// TODO make this class internal
-class ChatApi(private val realtimeClient: RealtimeClient, private val clientId: String) {
+internal class ChatApi(private val realtimeClient: RealtimeClient, private val clientId: String) {
 
     /**
      * Get messages from the Chat Backend
      *
      * @return paginated result with messages
      */
-    suspend fun getMessages(roomId: String, params: QueryOptions): PaginatedResult<Message> {
+    suspend fun getMessages(roomId: String, options: QueryOptions, fromSerial: String? = null): PaginatedResult<Message> {
+        val baseParams = options.toParams()
+        val params = fromSerial?.let { baseParams + Param("fromSerial", it) } ?: baseParams
         return makeAuthorizedPaginatedRequest(
             url = "/chat/v1/rooms/$roomId/messages",
             method = "GET",
-            params = params.toParams(),
+            params = params,
         ) {
             Message(
                 timeserial = it.requireString("timeserial"),
@@ -137,17 +135,6 @@ class ChatApi(private val realtimeClient: RealtimeClient, private val clientId:
     }
 }
 
-private fun JsonElement?.toRequestBody(useBinaryProtocol: Boolean = false): HttpCore.RequestBody =
-    HttpUtils.requestBodyFromGson(this, useBinaryProtocol)
-
-private fun Map<String, String>.toJson() = JsonObject().apply {
-    forEach { (key, value) -> addProperty(key, value) }
-}
-
-private fun JsonElement.toMap() = buildMap<String, String> {
-    requireJsonObject().entrySet().filter { (_, value) -> value.isJsonPrimitive }.forEach { (key, value) -> put(key, value.asString) }
-}
-
 private fun QueryOptions.toParams() = buildList {
     start?.let { add(Param("start", it)) }
     end?.let { add(Param("end", it)) }
@@ -162,67 +149,3 @@ private fun QueryOptions.toParams() = buildList {
         ),
     )
 }
-
-private fun JsonElement.requireJsonObject(): JsonObject {
-    if (!isJsonObject) {
-        throw AblyException.fromErrorInfo(
-            ErrorInfo("Response value expected to be JsonObject, got primitive instead", HttpStatusCodes.InternalServerError),
-        )
-    }
-    return asJsonObject
-}
-
-private fun JsonElement.requireString(memberName: String): String {
-    val memberElement = requireField(memberName)
-    if (!memberElement.isJsonPrimitive) {
-        throw AblyException.fromErrorInfo(
-            ErrorInfo(
-                "Value for \"$memberName\" field expected to be JsonPrimitive, got object instead",
-                HttpStatusCodes.InternalServerError,
-            ),
-        )
-    }
-    return memberElement.asString
-}
-
-private fun JsonElement.requireLong(memberName: String): Long {
-    val memberElement = requireJsonPrimitive(memberName)
-    try {
-        return memberElement.asLong
-    } catch (formatException: NumberFormatException) {
-        throw AblyException.fromErrorInfo(
-            formatException,
-            ErrorInfo("Required numeric field \"$memberName\" is not a valid long", HttpStatusCodes.InternalServerError),
-        )
-    }
-}
-
-private fun JsonElement.requireInt(memberName: String): Int {
-    val memberElement = requireJsonPrimitive(memberName)
-    try {
-        return memberElement.asInt
-    } catch (formatException: NumberFormatException) {
-        throw AblyException.fromErrorInfo(
-            formatException,
-            ErrorInfo("Required numeric field \"$memberName\" is not a valid int", HttpStatusCodes.InternalServerError),
-        )
-    }
-}
-
-private fun JsonElement.requireJsonPrimitive(memberName: String): JsonPrimitive {
-    val memberElement = requireField(memberName)
-    if (!memberElement.isJsonPrimitive) {
-        throw AblyException.fromErrorInfo(
-            ErrorInfo(
-                "Value for \"$memberName\" field expected to be JsonPrimitive, got object instead",
-                HttpStatusCodes.InternalServerError,
-            ),
-        )
-    }
-    return memberElement.asJsonPrimitive
-}
-
-private fun JsonElement.requireField(memberName: String): JsonElement = requireJsonObject().get(memberName)
-    ?: throw AblyException.fromErrorInfo(
-        ErrorInfo("Required field \"$memberName\" is missing", HttpStatusCodes.InternalServerError),
-    )

chat-android/src/main/java/com/ably/chat/ChatClient.kt

@@ -37,7 +37,8 @@ interface ChatClient {
     val clientOptions: ClientOptions
 }
 
-fun ChatClient(realtimeClient: RealtimeClient, clientOptions: ClientOptions): ChatClient = DefaultChatClient(realtimeClient, clientOptions)
+fun ChatClient(realtimeClient: RealtimeClient, clientOptions: ClientOptions = ClientOptions()): ChatClient =
+    DefaultChatClient(realtimeClient, clientOptions)
 
 internal class DefaultChatClient(
     override val realtime: RealtimeClient,

chat-android/src/main/java/com/ably/chat/ConnectionStatus.kt

@@ -25,13 +25,7 @@ interface ConnectionStatus {
      * Registers a listener that will be called whenever the connection status changes.
      * @param listener The function to call when the status changes.
      */
-    fun on(listener: Listener)
-
-    /**
-     * Unregisters a listener
-     * @param listener The function to call when the status changes.
-     */
-    fun off(listener: Listener)
+    fun on(listener: Listener): Subscription
 
     /**
      * An interface for listening to changes for the connection status

chat-android/src/main/java/com/ably/chat/EmitsDiscontinuities.kt

@@ -10,13 +10,7 @@ interface EmitsDiscontinuities {
      * Register a listener to be called when a discontinuity is detected.
      * @param listener The listener to be called when a discontinuity is detected.
      */
-    fun onDiscontinuity(listener: Listener)
-
-    /**
-     * Unregister a listener to be called when a discontinuity is detected.
-     * @param listener The listener
-     */
-    fun offDiscontinuity(listener: Listener)
+    fun onDiscontinuity(listener: Listener): Subscription
 
     /**
      * An interface for listening when discontinuity happens

chat-android/src/main/java/com/ably/chat/JsonUtils.kt

@@ -0,0 +1,84 @@
+package com.ably.chat
+
+import com.google.gson.JsonElement
+import com.google.gson.JsonObject
+import com.google.gson.JsonPrimitive
+import io.ably.lib.http.HttpCore
+import io.ably.lib.http.HttpUtils
+import io.ably.lib.types.AblyException
+import io.ably.lib.types.ErrorInfo
+
+internal fun JsonElement?.toRequestBody(useBinaryProtocol: Boolean = false): HttpCore.RequestBody =
+    HttpUtils.requestBodyFromGson(this, useBinaryProtocol)
+
+internal fun Map<String, String>.toJson() = JsonObject().apply {
+    forEach { (key, value) -> addProperty(key, value) }
+}
+
+internal fun JsonElement.toMap() = buildMap<String, String> {
+    requireJsonObject().entrySet().filter { (_, value) -> value.isJsonPrimitive }.forEach { (key, value) -> put(key, value.asString) }
+}
+
+internal fun JsonElement.requireJsonObject(): JsonObject {
+    if (!isJsonObject) {
+        throw AblyException.fromErrorInfo(
+            ErrorInfo("Response value expected to be JsonObject, got primitive instead", HttpStatusCodes.InternalServerError),
+        )
+    }
+    return asJsonObject
+}
+
+internal fun JsonElement.requireString(memberName: String): String {
+    val memberElement = requireField(memberName)
+    if (!memberElement.isJsonPrimitive) {
+        throw AblyException.fromErrorInfo(
+            ErrorInfo(
+                "Value for \"$memberName\" field expected to be JsonPrimitive, got object instead",
+                HttpStatusCodes.InternalServerError,
+            ),
+        )
+    }
+    return memberElement.asString
+}
+
+internal fun JsonElement.requireLong(memberName: String): Long {
+    val memberElement = requireJsonPrimitive(memberName)
+    try {
+        return memberElement.asLong
+    } catch (formatException: NumberFormatException) {
+        throw AblyException.fromErrorInfo(
+            formatException,
+            ErrorInfo("Required numeric field \"$memberName\" is not a valid long", HttpStatusCodes.InternalServerError),
+        )
+    }
+}
+
+internal fun JsonElement.requireInt(memberName: String): Int {
+    val memberElement = requireJsonPrimitive(memberName)
+    try {
+        return memberElement.asInt
+    } catch (formatException: NumberFormatException) {
+        throw AblyException.fromErrorInfo(
+            formatException,
+            ErrorInfo("Required numeric field \"$memberName\" is not a valid int", HttpStatusCodes.InternalServerError),
+        )
+    }
+}
+
+internal fun JsonElement.requireJsonPrimitive(memberName: String): JsonPrimitive {
+    val memberElement = requireField(memberName)
+    if (!memberElement.isJsonPrimitive) {
+        throw AblyException.fromErrorInfo(
+            ErrorInfo(
+                "Value for \"$memberName\" field expected to be JsonPrimitive, got object instead",
+                HttpStatusCodes.InternalServerError,
+            ),
+        )
+    }
+    return memberElement.asJsonPrimitive
+}
+
+internal fun JsonElement.requireField(memberName: String): JsonElement = requireJsonObject().get(memberName)
+    ?: throw AblyException.fromErrorInfo(
+        ErrorInfo("Required field \"$memberName\" is missing", HttpStatusCodes.InternalServerError),
+    )