Remove the need to explicitly include custom workflows and actions.

Change-Id: I914b3f16bba8ad261214164c57c9644299856f98
Closes-Bug: #1770567

o11nplugin-contrail-config/src/main/kotlin/net/juniper/contrail/vro/config/ClassUtils.kt

@@ -135,6 +135,9 @@ val Method.objectReferenceAttributeClass: Class<*>? get() =
 val Method.isPublic get() =
     Modifier.isPublic(modifiers)
 
+val Method.isStatic get() =
+    Modifier.isStatic(modifiers)
+
 val <T> Class<T>.isAbstract: Boolean get() =
     Modifier.isAbstract(modifiers)
 
@@ -176,7 +179,7 @@ private fun <T> Class<T>.subclassesIn(packageName: String): List<Class<*>> =
         .filter { it.isSubclassOf(this) }
         .toList()
 
-private fun classesIn(packageName: String): Sequence<Class<*>> =
+fun classesIn(packageName: String): Sequence<Class<*>> =
     ClassPath.from(loader).getTopLevelClassesRecursive(packageName).asSequence()
         .map { classForName(it.name) }
         .filterNotNull()

o11nplugin-contrail-tests/src/test/groovy/net/juniper/contrail/vro/tests/actions/ActionSpec.groovy

@@ -6,7 +6,7 @@ package net.juniper.contrail.vro.tests.actions
 
 import net.juniper.contrail.vro.tests.ScriptTestEngine
 import spock.lang.Specification
-import static net.juniper.contrail.vro.workflows.custom.CustomActionsKt.loadCustomActions
+import static net.juniper.contrail.vro.workflows.custom.Custom.loadCustomActions
 import static net.juniper.contrail.vro.tests.JsTesterKt.utilsName
 
 abstract class ActionSpec extends Specification {

o11nplugin-contrail-tests/src/test/groovy/net/juniper/contrail/vro/tests/workflows/WorkflowSpec.groovy

@@ -22,7 +22,7 @@ import java.nio.file.Paths
 import static net.juniper.contrail.vro.config.ProjectInfoKt.globalProjectInfo
 import static net.juniper.contrail.vro.schema.SchemaKt.buildSchema
 import static net.juniper.contrail.vro.tests.JsTesterKt.utilsName
-import static net.juniper.contrail.vro.workflows.custom.CustomWorkflowsKt.loadCustomWorkflows
+import static net.juniper.contrail.vro.workflows.custom.Custom.loadCustomWorkflows
 
 abstract class WorkflowSpec extends Specification {
     Dependencies dependencies

o11nplugin-contrail-workflows/src/main/kotlin/net/juniper/contrail/vro/workflows/custom/Custom.kt

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2018 Juniper Networks, Inc. All rights reserved.
+ */
+
+@file:JvmName("Custom")
+
+package net.juniper.contrail.vro.workflows.custom
+
+import net.juniper.contrail.vro.workflows.dsl.WorkflowDefinition
+import net.juniper.contrail.vro.schema.Schema
+import net.juniper.contrail.vro.workflows.model.Action
+
+fun loadCustomWorkflows(schema: Schema): List<WorkflowDefinition> =
+    WorkflowLoader.load(schema).toList()
+
+fun loadCustomActions(version: String, packageName: String): List<Action> =
+    ActionLoader.load().map { it(version, packageName) }.toList()

o11nplugin-contrail-workflows/src/main/kotlin/net/juniper/contrail/vro/workflows/custom/Loaders.kt

@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2018 Juniper Networks, Inc. All rights reserved.
+ */
+
+package net.juniper.contrail.vro.workflows.custom
+
+import net.juniper.contrail.vro.config.classesIn
+import net.juniper.contrail.vro.config.isStatic
+import net.juniper.contrail.vro.schema.Schema
+import net.juniper.contrail.vro.workflows.dsl.WorkflowDefinition
+import java.lang.reflect.Method
+
+private val workflowScriptsDirectory = "workflows"
+private val actionScriptsDirectory = "actions"
+
+object ScriptLoader {
+    private fun load(path: String): String =
+        ScriptLoader::class.java
+            .getResourceAsStream(path)
+            .bufferedReader()
+            .use { it.readText() }
+
+    fun loadActionScript(name: String): String =
+        load("/$actionScriptsDirectory/$name.js")
+
+    fun loadWorkflowScript(name: String): String =
+        load("/$workflowScriptsDirectory/$name.js")
+}
+
+object WorkflowLoader {
+    fun load(schema: Schema): Sequence<WorkflowDefinition> =
+        classesIn(WorkflowLoader::class.java.`package`.name)
+        .filter { it.hasWorkflowDefinitions }
+        .flatMap { it.workflowDefinitions(schema) }
+}
+
+object ActionLoader {
+    fun load(): Sequence<ActionDefinition> =
+        classesIn(ActionLoader::class.java.`package`.name)
+        .filter { it.hasActionDefinitions }
+        .flatMap { it.actionDefinitions() }
+}
+
+private val Class<*>.hasWorkflowDefinitions get() =
+    declaredMethods.any { it.definesWorkflow }
+
+private val Class<*>.hasActionDefinitions get() =
+    declaredMethods.any { it.definesAction }
+
+private fun Class<*>.workflowDefinitions(schema: Schema) =
+    declaredMethods.asSequence()
+        .filter { it.definesWorkflow }
+        .map { it.createWorkflowDefinition(schema) }
+
+private fun Class<*>.actionDefinitions() =
+    declaredMethods.asSequence()
+        .filter { it.definesAction }
+        .map { it.createActionDefinition() }
+
+private fun Method.createWorkflowDefinition(schema: Schema): WorkflowDefinition = when {
+    takesNoParameters -> invoke(declaringClass)
+    takesOnlySchema -> invoke(declaringClass, schema)
+    else -> throw IllegalArgumentException("Cannot create workflow definition using method '$this' of class '$declaringClass'.")
+} as WorkflowDefinition
+
+private fun Method.createActionDefinition(): ActionDefinition = when {
+    takesNoParameters -> invoke(declaringClass)
+    else -> throw IllegalArgumentException("Cannot create action definition using method '$this' of class '$declaringClass'.")
+} as ActionDefinition
+
+private val Method.definesWorkflow get() =
+    isStatic && returnType == WorkflowDefinition::class.java && takesWorkflowDefinitionParameters
+
+private val Method.takesWorkflowDefinitionParameters get() =
+    takesNoParameters || takesOnlySchema
+
+private val Method.takesNoParameters get() =
+    parameterCount == 0
+
+private val Method.takesOnlySchema get() =
+    parameterCount == 1 && parameters[0].type == Schema::class.java
+
+private val Method.definesAction get() =
+    isStatic && returnType == ActionDefinition::class.java && takesNoParameters
+

o11nplugin-contrail-workflows/src/main/kotlin/net/juniper/contrail/vro/workflows/custom/Utils.kt

@@ -11,23 +11,6 @@ import net.juniper.contrail.vro.workflows.dsl.inCategory
 import net.juniper.contrail.vro.workflows.dsl.withScript
 import net.juniper.contrail.vro.workflows.dsl.workflow
 
-val workflowScriptsDirectory = "workflows"
-val actionScriptsDirectory = "actions"
-
-object ScriptLoader {
-    private fun load(path: String): String =
-        ScriptLoader::class.java
-            .getResourceAsStream(path)
-            .bufferedReader()
-            .use { it.readText() }
-
-    fun loadActionScript(name: String): String =
-        load("/$actionScriptsDirectory/$name.js")
-
-    fun loadWorkflowScript(name: String): String =
-        load("/$workflowScriptsDirectory/$name.js")
-}
-
 fun WorkflowDefinition.withScriptFile(name: String, setup: ParameterDefinition) =
     withScript(ScriptLoader.loadWorkflowScript(name), setup)