Add ApolloCompilerPluginProvider (apollographql#5865)

* Add logger and arguments

* small tweak to the KDoc

* improve migration guide

* more KDoc

* Update libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/ApolloCompilerPluginEnvironment.kt

Co-authored-by: Benoit 'BoD' Lubek <[email protected]>

* Update libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/ApolloCompilerPluginEnvironment.kt

Co-authored-by: Benoit 'BoD' Lubek <[email protected]>

* remove exception, messager and add comment

---------

Co-authored-by: Benoit 'BoD' Lubek <[email protected]>

Author: martinbonnin

docs/source/migration/4.0.mdx

@@ -330,9 +330,46 @@ If you are using `packageNamesFromFilePaths` and `schemaFile`, you'll need to us
 ```
 
 <Note>
+
 Apollo Kotlin 3 was using the operation root directories to compute the schema normalized path which could be wrong in some edge cases. Using fileTree ensures the normalized path is consistent.
 </Note>
 
+### Migrating to ApolloCompilerPlugin
+
+4.0 introduces `ApolloCompilerPlugin` as a way to customize code generation. `ApolloCompilerPlugin` are loaded using the [ServiceLoader](https://docs.oracle.com/javase/8/docs/api/java/util/ServiceLoader.html) API and run in a separate classloader from your Gradle build. As a result, using  `Service.operationIdGenerator`/`Service.operationOutputGenerator` together with `ApolloCompilerPlugin` is not possible.
+
+`Service.operationIdGenerator`/`Service.operationOutputGenerator` are deprecated and will be removed in a future release. You can migrate to `ApolloCompilerPlugin` using the instructions [from the dedicated page](https://www.apollographql.com/docs/kotlin/v4/advanced/compiler-plugins) and the `ApolloCompilerPlugin.operationIds()` method:
+
+```kotlin
+// Replace (in your build scripts) 
+val operationOutputGenerator = object: OperationOutputGenerator {
+  override fun generate(operationDescriptorList: Collection<OperationDescriptor>): OperationOutput {
+    return operationDescriptorList.associateBy {
+      it.source.sha1()
+    }
+  }
+  override val version: String = "v1"
+}
+
+// Or, if using OperationIdGenerator, replace
+val operationIdGenerator = object: OperationIdGenerator {
+  override fun apply(operationDocument: String, operationName: String): String {
+    return operationDocument.sha1()
+  }
+
+  override val version: String = "v1"
+}
+
+// With (in your build compiler plugin module) 
+class MyPlugin: ApolloCompilerPlugin {
+  override fun operationIds(descriptors: List<OperationDescriptor>): List<OperationId>? {
+    return descriptors.map {
+      OperationId(it.source.sha1(), it.name)
+    }
+  }
+}
+```
+
 ### Misc
 
 * Publishing is no longer configured automatically.
@@ -526,6 +563,7 @@ apolloClient.query().rxSingle()
 apolloClient.query().toFlow().asFlowable().firstOrError()
 ```
 
+
 ## Example of a migration
 
 If you are looking for inspiration, we updated the [3.x integration tests to use 4.0](https://github.com/apollographql/apollo-kotlin/pull/5418/). If you have an open source project that migrated, feel free to share it and we'll include it here.

libraries/apollo-compiler/api/apollo-compiler.api

@@ -653,6 +653,9 @@ public final class com/apollographql/apollo3/compiler/codegen/kotlin/helpers/Add
 	public static final fun addInternal (Lcom/squareup/kotlinpoet/FileSpec$Builder;Ljava/util/List;)Lcom/squareup/kotlinpoet/FileSpec$Builder;
 }
 
+public final class com/apollographql/apollo3/compiler/internal/GradleCompilerPluginLogger$Companion {
+}
+
 public final class com/apollographql/apollo3/compiler/ir/IrAccessor$Companion {
 	public final fun serializer ()Lkotlinx/serialization/KSerializer;
 }

libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/ApolloCompilerPluginEnvironment.kt

@@ -0,0 +1,18 @@
+package com.apollographql.apollo3.compiler
+
+import com.apollographql.apollo3.annotations.ApolloExperimental
+
+/**
+ * [ApolloCompilerPluginEnvironment] contains the environment where the Apollo compiler is run.
+ */
+@ApolloExperimental
+class ApolloCompilerPluginEnvironment(
+    /**
+     * Arguments as passed from the Gradle plugin
+     */
+    val arguments: Map<String, Any?>,
+    /**
+     * A logger that can be used by the plugin.
+     */
+    val logger: ApolloCompilerPluginLogger,
+)

libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/ApolloCompilerPluginLogger.kt

@@ -0,0 +1,16 @@
+package com.apollographql.apollo3.compiler
+
+import com.apollographql.apollo3.annotations.ApolloExperimental
+
+/**
+ * [ApolloCompilerPluginLogger] allows logging from the context of the Apollo compiler.
+ *
+ * Typically, the Apollo compiler is run from an isolated classloader and cannot use the Gradle logging functions but can respect the logging level set by the user.
+ */
+@ApolloExperimental
+interface ApolloCompilerPluginLogger {
+  fun logging(message: String)
+  fun info(message: String)
+  fun warn(message: String)
+  fun error(message: String)
+}

libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/ApolloCompilerPluginProvider.kt

@@ -0,0 +1,17 @@
+package com.apollographql.apollo3.compiler
+
+import com.apollographql.apollo3.annotations.ApolloExperimental
+
+/**
+ * [ApolloCompilerPluginProvider] is entry point for creating [ApolloCompilerPlugin].
+ *
+ * [ApolloCompilerPluginProvider] is created by [java.util.ServiceLoader], make sure to include a matching `META-INF/services` resource.
+ */
+@ApolloExperimental
+fun interface ApolloCompilerPluginProvider {
+  /**
+   * Creates the [ApolloCompilerPlugin]
+   */
+  fun create(environment: ApolloCompilerPluginEnvironment): ApolloCompilerPlugin
+}
+

libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/internal/GradleCompilerPluginLogger.kt

@@ -0,0 +1,39 @@
+package com.apollographql.apollo3.compiler.internal
+
+import com.apollographql.apollo3.annotations.ApolloInternal
+import com.apollographql.apollo3.compiler.ApolloCompilerPluginLogger
+
+@ApolloInternal
+class GradleCompilerPluginLogger(val loglevel: Int) : ApolloCompilerPluginLogger {
+
+  override fun logging(message: String) {
+    if (loglevel <= LOGGING_LEVEL_LOGGING)
+      println("v: [apollo] $message")
+  }
+
+  override fun info(message: String) {
+    if (loglevel <= LOGGING_LEVEL_INFO)
+      println("i: [apollo] $message")
+  }
+
+  override fun warn(message: String) {
+    if (loglevel <= LOGGING_LEVEL_WARN)
+      println("w: [apollo] $message")
+  }
+
+  override fun error(message: String) {
+    if (loglevel <= LOGGING_LEVEL_ERROR)
+      println("e: [apollo] $message")
+  }
+
+  companion object {
+    /**
+     * Matches Gradle LogLevel
+     * See https://github.com/gradle/gradle/blob/71f42531a742bc263c61f1d0dc21bb6570cc817b/platforms/core-runtime/logging-api/src/main/java/org/gradle/api/logging/LogLevel.java#L21
+     */
+    const val LOGGING_LEVEL_LOGGING = 0
+    const val LOGGING_LEVEL_INFO = 1
+    const val LOGGING_LEVEL_WARN = 3
+    const val LOGGING_LEVEL_ERROR = 5
+  }
+}

libraries/apollo-compiler/src/main/kotlin/com/apollographql/apollo3/compiler/operationoutput/OperationOutput.kt

@@ -19,7 +19,7 @@ class OperationDescriptor(
      */
     val name: String,
     /**
-     * The source of the operation as it is sent over the wire, including fragments
+     * The source of the operation document as it is sent over the wire, including fragments
      */
     val source: String,
     /**
@@ -30,6 +30,14 @@ class OperationDescriptor(
 
 /**
  * The id of an operation associated with its name so that it can be looked up.
+ *
+ * @param id the generated id for the operation
+ * @param name the name of the operation, such as "FooQuery" below
+ * ```graphql
+ * query FooQuery {
+ *   foo
+ * }
+ * ```
  */
 class OperationId(val id: String, val name: String)
 

libraries/apollo-gradle-plugin-external/src/main/kotlin/com/apollographql/apollo3/gradle/api/CompilerPlugin.kt

@@ -0,0 +1,21 @@
+package com.apollographql.apollo3.gradle.api
+
+import com.apollographql.apollo3.annotations.ApolloExperimental
+
+@ApolloExperimental
+interface CompilerPlugin {
+  /**
+   * Adds the given argument to the [com.apollographql.apollo3.compiler.ApolloCompilerPlugin].
+   * If two arguments are added with the same name, the second one overwrites the first one.
+   *
+   * @param name the name of the argument
+   * @param value the value of the argument. One of:
+   * - [String]
+   * - [Int]
+   * - [Double]
+   * - [Boolean]
+   * - [List]
+   * - [Map]
+   */
+  fun argument(name: String, value: Any)
+}

libraries/apollo-gradle-plugin-external/src/main/kotlin/com/apollographql/apollo3/gradle/api/Service.kt

@@ -907,4 +907,7 @@ interface Service {
   }
 
   fun plugin(dependencyNotation: Any)
+
+  @ApolloExperimental
+  fun plugin(dependencyNotation: Any, block: Action<CompilerPlugin>)
 }

libraries/apollo-gradle-plugin-external/src/main/kotlin/com/apollographql/apollo3/gradle/internal/ApolloGenerateIrOperationsTask.kt

@@ -6,10 +6,8 @@ import com.apollographql.apollo3.compiler.toIrOperations
 import com.apollographql.apollo3.compiler.toIrOptions
 import com.apollographql.apollo3.compiler.writeTo
 import com.apollographql.apollo3.gradle.internal.ApolloGenerateSourcesFromIrTask.Companion.findCodegenSchemaFile
-import org.gradle.api.DefaultTask
 import org.gradle.api.file.ConfigurableFileCollection
 import org.gradle.api.file.RegularFileProperty
-import org.gradle.api.tasks.Classpath
 import org.gradle.api.tasks.InputFile
 import org.gradle.api.tasks.InputFiles
 import org.gradle.api.tasks.OutputFile
@@ -22,7 +20,7 @@ import org.gradle.workers.WorkerExecutor
 import java.io.File
 import javax.inject.Inject
 
-abstract class ApolloGenerateIrOperationsTask: DefaultTask() {
+abstract class ApolloGenerateIrOperationsTask: ApolloTaskWithClasspath() {
   @get:InputFiles
   @get:PathSensitive(PathSensitivity.RELATIVE)
   abstract val codegenSchemaFiles: ConfigurableFileCollection
@@ -42,9 +40,6 @@ abstract class ApolloGenerateIrOperationsTask: DefaultTask() {
   @get:OutputFile
   abstract val irOperationsFile: RegularFileProperty
 
-  @get:Classpath
-  abstract val classpath: ConfigurableFileCollection
-
   @Inject
   abstract fun getWorkerExecutor(): WorkerExecutor
 
@@ -61,6 +56,8 @@ abstract class ApolloGenerateIrOperationsTask: DefaultTask() {
       it.upstreamIrFiles = upstreamIrFiles.isolate()
       it.irOptionsFile.set(irOptionsFile)
       it.irOperationsFile.set(irOperationsFile)
+      it.arguments = arguments.get()
+      it.logLevel = logLevel.get().ordinal
     }
   }
 }
@@ -69,7 +66,7 @@ private abstract class GenerateIrOperations : WorkAction<GenerateIrOperationsPar
   override fun execute() {
     with(parameters) {
       val upstreamIrOperations = upstreamIrFiles.toInputFiles().map { it.file.toIrOperations() }
-      val plugin = apolloCompilerPlugin()
+      val plugin = apolloCompilerPlugin(arguments, logLevel)
 
       ApolloCompiler.buildIrOperations(
           executableFiles = graphqlFiles.toInputFiles(),
@@ -89,4 +86,6 @@ private interface GenerateIrOperationsParameters : WorkParameters {
   var upstreamIrFiles: List<Pair<String, File>>
   val irOptionsFile: RegularFileProperty
   val irOperationsFile: RegularFileProperty
+  var arguments: Map<String, Any?>
+  var logLevel: Int
 }