Add cart module and requests queue helper

cart-utils/.gitignore

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+/build

cart-utils/build.gradle

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+apply from: "../android-configs/lib-config.gradle"
+
+dependencies {
+    def coroutinesVersion = '1.6.4'
+    def junitVersion = '4.13.2'
+
+    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core")
+    testImplementation("junit:junit")
+
+    constraints {
+        implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core") {
+            version {
+                require(coroutinesVersion)
+            }
+        }
+        testImplementation("junit:junit") {
+            version {
+                require(junitVersion)
+            }
+        }
+    }
+}

cart-utils/src/main/AndroidManifest.xml

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+<manifest package="ru.touchin.roboswag.core.cart_utils" />

cart-utils/src/main/java/ru/touchin/roboswag/cart_utils/requests_qeue/RequestsQueue.kt

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+package ru.touchin.roboswag.cart_utils.requests_qeue
+
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.Channel
+import kotlinx.coroutines.flow.consumeAsFlow
+import kotlinx.coroutines.flow.launchIn
+import kotlinx.coroutines.flow.onEach
+
+/**
+ * Queue for abstract requests which will be executed one after another
+ */
+typealias Request<TResponse> = suspend () -> TResponse
+
+class RequestsQueue<TRequest : Request<*>> {
+
+    private val requestChannel = Channel<TRequest>(capacity = Channel.BUFFERED)
+
+    fun initRequestsExecution(
+            coroutineScope: CoroutineScope,
+            executeRequestAction: suspend (TRequest) -> Unit,
+    ) {
+        requestChannel
+                .consumeAsFlow()
+                .onEach { executeRequestAction.invoke(it) }
+                .launchIn(coroutineScope)
+    }
+
+    fun addToQueue(request: TRequest) {
+        requestChannel.trySend(request)
+    }
+
+    fun clearQueue() {
+        while (hasPendingRequests()) requestChannel.tryReceive()
+    }
+
+    @OptIn(ExperimentalCoroutinesApi::class)
+    fun hasPendingRequests() = !requestChannel.isEmpty
+}