m6l1 - Chain of Responsibility

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonMain/kotlin/ru/otus/otuskotlin/marketplace/cor/CorDslMarker.kt

@@ -0,0 +1,4 @@
+package ru.otus.otuskotlin.marketplace.cor
+
+@DslMarker
+annotation class CorDslMarker

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonMain/kotlin/ru/otus/otuskotlin/marketplace/cor/corDsl.kt

@@ -0,0 +1,83 @@
+package ru.otus.otuskotlin.marketplace.cor
+
+import ru.otus.otuskotlin.marketplace.cor.handlers.CorChainDsl
+import ru.otus.otuskotlin.marketplace.cor.handlers.CorWorkerDsl
+
+/**
+ * Базовый билдер (dsl)
+ */
+@CorDslMarker
+interface ICorExecDsl<T> {
+    var title: String
+    var description: String
+    fun on(function: suspend T.() -> Boolean)
+    fun except(function: suspend T.(e: Throwable) -> Unit)
+
+    fun build(): ICorExec<T>
+}
+
+/**
+ * Билдер (dsl) для цепочек (chain)
+ */
+@CorDslMarker
+interface ICorChainDsl<T> : ICorExecDsl<T> {
+    fun add(worker: ICorExecDsl<T>)
+}
+
+/**
+ * Билдер (dsl) для рабочих (worker)
+ */
+@CorDslMarker
+interface ICorWorkerDsl<T> : ICorExecDsl<T> {
+    fun handle(function: suspend T.() -> Unit)
+}
+
+/**
+ * Точка входа в dsl построения цепочек.
+ * Элементы исполняются последовательно.
+ *
+ * Пример:
+ * ```
+ *  rootChain<SomeContext> {
+ *      worker {
+ *      }
+ *      chain {
+ *          worker(...) {
+ *          }
+ *          worker(...) {
+ *          }
+ *      }
+ *  }
+ * ```
+ */
+fun <T> rootChain(function: ICorChainDsl<T>.() -> Unit): ICorChainDsl<T> = CorChainDsl<T>().apply(function)
+
+
+/**
+ * Создает цепочку, элементы которой исполняются последовательно.
+ */
+fun <T> ICorChainDsl<T>.chain(function: ICorChainDsl<T>.() -> Unit) {
+    add(CorChainDsl<T>().apply(function))
+}
+
+/**
+ * Создает рабочего
+ */
+fun <T> ICorChainDsl<T>.worker(function: ICorWorkerDsl<T>.() -> Unit) {
+    add(CorWorkerDsl<T>().apply(function))
+}
+
+/**
+ * Создает рабочего с on и except по умолчанию
+ */
+fun <T> ICorChainDsl<T>.worker(
+    title: String,
+    description: String = "",
+    blockHandle: T.() -> Unit
+) {
+    add(CorWorkerDsl<T>().also {
+        it.title = title
+        it.description = description
+        it.handle(blockHandle)
+    })
+}

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonMain/kotlin/ru/otus/otuskotlin/marketplace/cor/handlers/AbstractCorExec.kt

@@ -0,0 +1,42 @@
+package ru.otus.otuskotlin.marketplace.cor.handlers
+
+import ru.otus.otuskotlin.marketplace.cor.ICorExec
+import ru.otus.otuskotlin.marketplace.cor.ICorExecDsl
+
+abstract class AbstractCorExec<T>(
+    override val title: String,
+    override val description: String = "",
+    private val blockOn: suspend T.() -> Boolean = { true },
+    private val blockExcept: suspend T.(Throwable) -> Unit = {},
+): ICorExec<T> {
+    protected abstract suspend fun handle(context: T)
+
+    private suspend fun on(context: T): Boolean = context.blockOn()
+    private suspend fun except(context: T, e: Throwable) = context.blockExcept(e)
+
+    override suspend fun exec(context: T) {
+        if (on(context)) {
+            try {
+                handle(context)
+            } catch (e: Throwable) {
+                except(context, e)
+            }
+        }
+    }
+}
+
+abstract class CorExecDsl<T> : ICorExecDsl<T> {
+    protected var blockOn: suspend T.() -> Boolean = { true }
+    protected var blockExcept: suspend T.(e: Throwable) -> Unit = { e: Throwable -> throw e }
+
+    override var title: String = ""
+    override var description: String = ""
+
+    override fun on(function: suspend T.() -> Boolean) {
+        blockOn = function
+    }
+
+    override fun except(function: suspend T.(e: Throwable) -> Unit) {
+        blockExcept = function
+    }
+}

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonMain/kotlin/ru/otus/otuskotlin/marketplace/cor/handlers/CorChain.kt

@@ -0,0 +1,40 @@
+package ru.otus.otuskotlin.marketplace.cor.handlers
+
+import ru.otus.otuskotlin.marketplace.cor.CorDslMarker
+import ru.otus.otuskotlin.marketplace.cor.ICorChainDsl
+import ru.otus.otuskotlin.marketplace.cor.ICorExec
+import ru.otus.otuskotlin.marketplace.cor.ICorExecDsl
+
+/**
+ * Реализация цепочки (chain), которая исполняет свои вложенные цепочки и рабочие
+ */
+class CorChain<T>(
+    private val execs: List<ICorExec<T>>,
+    title: String,
+    description: String = "",
+    blockOn: suspend T.() -> Boolean = { true },
+    blockExcept: suspend T.(Throwable) -> Unit = {},
+) : AbstractCorExec<T>(title, description, blockOn, blockExcept) {
+    override suspend fun handle(context: T) {
+        execs.forEach {
+            it.exec(context)
+        }
+    }
+}
+
+@CorDslMarker
+class CorChainDsl<T>(
+) : CorExecDsl<T>(), ICorChainDsl<T> {
+    private val workers: MutableList<ICorExecDsl<T>> = mutableListOf()
+    override fun add(worker: ICorExecDsl<T>) {
+        workers.add(worker)
+    }
+
+    override fun build(): ICorExec<T> = CorChain(
+        title = title,
+        description = description,
+        execs = workers.map { it.build() },
+        blockOn = blockOn,
+        blockExcept = blockExcept
+    )
+}

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonMain/kotlin/ru/otus/otuskotlin/marketplace/cor/handlers/CorWorker.kt

@@ -0,0 +1,32 @@
+package ru.otus.otuskotlin.marketplace.cor.handlers
+
+import ru.otus.otuskotlin.marketplace.cor.CorDslMarker
+import ru.otus.otuskotlin.marketplace.cor.ICorExec
+import ru.otus.otuskotlin.marketplace.cor.ICorWorkerDsl
+
+class CorWorker<T>(
+    title: String,
+    description: String = "",
+    blockOn: suspend T.() -> Boolean = { true },
+    private val blockHandle: suspend T.() -> Unit = {},
+    blockExcept: suspend T.(Throwable) -> Unit = {},
+) : AbstractCorExec<T>(title, description, blockOn, blockExcept) {
+    override suspend fun handle(context: T) = blockHandle(context)
+}
+
+@CorDslMarker
+class CorWorkerDsl<T> : CorExecDsl<T>(), ICorWorkerDsl<T> {
+    private var blockHandle: suspend T.() -> Unit = {}
+    override fun handle(function: suspend T.() -> Unit) {
+        blockHandle = function
+    }
+
+    override fun build(): ICorExec<T> = CorWorker(
+        title = title,
+        description = description,
+        blockOn = blockOn,
+        blockHandle = blockHandle,
+        blockExcept = blockExcept
+    )
+
+}

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonTest/kotlin/ru/otus/otuskotlin/marketplace/cor/CorChainTest.kt

@@ -1,11 +1,13 @@
 package ru.otus.otuskotlin.marketplace.cor
 
 import kotlinx.coroutines.test.runTest
+import ru.otus.otuskotlin.marketplace.cor.handlers.CorChain
+import ru.otus.otuskotlin.marketplace.cor.handlers.CorWorker
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
 class CorChainTest {
-    /*@Test
+    @Test
     fun `chain should execute workers`() = runTest {
         val createWorker = { title: String ->
             CorWorker<TestContext>(
@@ -21,5 +23,5 @@ class CorChainTest {
         val ctx = TestContext()
         chain.exec(ctx)
         assertEquals("w1; w2; ", ctx.history)
-    }*/
+    }
 }

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonTest/kotlin/ru/otus/otuskotlin/marketplace/cor/CorDslTest.kt

@@ -6,7 +6,7 @@ import kotlin.test.assertEquals
 import kotlin.test.assertFails
 
 class CorBaseTest {
-    /*private suspend fun execute(dsl: ICorExecDsl<TestContext>): TestContext {
+    private suspend fun execute(dsl: ICorExecDsl<TestContext>): TestContext {
         val ctx = TestContext()
         dsl.build().exec(ctx)
         return ctx
@@ -100,6 +100,6 @@ class CorBaseTest {
 
     private fun ICorChainDsl<TestContext>.printResult() = worker(title = "Print example") {
         println("some = $some")
-    }*/
+    }
 }
 

ok-marketplace-libs/ok-marketplace-lib-cor/src/commonTest/kotlin/ru/otus/otuskotlin/marketplace/cor/CorWorkerTest.kt

@@ -1,11 +1,12 @@
 package ru.otus.otuskotlin.marketplace.cor
 
 import kotlinx.coroutines.test.runTest
+import ru.otus.otuskotlin.marketplace.cor.handlers.CorWorker
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
 class CorWorkerTest {
-    /*@Test
+    @Test
     fun `worker should execute handle`() = runTest {
         val worker = CorWorker<TestContext>(
             title = "w1",
@@ -39,5 +40,5 @@ class CorWorkerTest {
         worker.exec(ctx)
         assertEquals("some error", ctx.history)
     }
-    */
+
 }