Fix configuration cache and schema file auto detection

Closes #5455
Closes #5221

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

@@ -8,7 +8,6 @@ import org.gradle.api.provider.Property
 import org.gradle.api.tasks.Input
 import org.gradle.api.tasks.Internal
 import org.gradle.api.tasks.Optional
-import org.gradle.api.tasks.OutputFile
 import org.gradle.api.tasks.TaskAction
 import org.gradle.api.tasks.options.Option
 import java.io.File
@@ -50,8 +49,13 @@ abstract class ApolloDownloadSchemaTask : DefaultTask() {
   @get:Option(option = "schema", description = "path where the schema will be downloaded, relative to the root project directory")
   abstract val schema: Property<String>
 
-  @get:OutputFile
-  @get:Optional
+  /**
+   * This is not declared as an output as it triggers this Gradle error else:
+   * "Reason: Task ':root:generateServiceApolloCodegenSchema' uses this output of task ':root:downloadServiceApolloSchemaFromIntrospection' without declaring an explicit or implicit dependency."
+   *
+   * Since it's unlikely that users want to download the schema every time, just set it as an internal property.
+   */
+  @get:Internal
   abstract val outputFile: RegularFileProperty
 
   @get:Internal

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

@@ -21,6 +21,10 @@ abstract class ApolloGenerateCodegenSchemaTask : DefaultTask() {
   @get:PathSensitive(PathSensitivity.RELATIVE)
   abstract val schemaFiles: ConfigurableFileCollection
 
+  @get:InputFiles
+  @get:PathSensitive(PathSensitivity.RELATIVE)
+  abstract val fallbackSchemaFiles: ConfigurableFileCollection
+
   @get:InputFiles
   @get:PathSensitive(PathSensitivity.RELATIVE)
   abstract val upstreamSchemaFiles: ConfigurableFileCollection
@@ -47,7 +51,7 @@ abstract class ApolloGenerateCodegenSchemaTask : DefaultTask() {
     }
 
     ApolloCompiler.buildCodegenSchema(
-        schemaFiles = schemaFiles.files,
+        schemaFiles = schemaFiles.files.takeIf { it.isNotEmpty() } ?: fallbackSchemaFiles.files,
         logger = logger(),
         codegenSchemaOptions = codegenSchemaOptionsFile.get().asFile.toCodegenSchemaOptions(),
     ).writeTo(codegenSchemaFile.get().asFile)

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

@@ -20,6 +20,10 @@ abstract class ApolloGenerateSourcesTask : ApolloGenerateSourcesBaseTask() {
   @get:PathSensitive(PathSensitivity.RELATIVE)
   abstract val schemaFiles: ConfigurableFileCollection
 
+  @get:InputFiles
+  @get:PathSensitive(PathSensitivity.RELATIVE)
+  abstract val fallbackSchemaFiles: ConfigurableFileCollection
+
   @get:InputFile
   @get:PathSensitive(PathSensitivity.RELATIVE)
   abstract val codegenSchemaOptionsFile: RegularFileProperty
@@ -31,7 +35,7 @@ abstract class ApolloGenerateSourcesTask : ApolloGenerateSourcesBaseTask() {
   @TaskAction
   fun taskAction() {
     ApolloCompiler.buildSchemaAndOperationsSources(
-        schemaFiles = schemaFiles.files,
+        schemaFiles = schemaFiles.files.takeIf { it.isNotEmpty() } ?: fallbackSchemaFiles.files,
         executableFiles = graphqlFiles.files,
         codegenSchemaOptions = codegenSchemaOptionsFile.get().asFile.toCodegenSchemaOptions(),
         codegenOptions = codegenOptionsFile.get().asFile.toCodegenOptions(),

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

@@ -29,7 +29,6 @@ import org.gradle.api.attributes.Usage
 import org.gradle.api.component.AdhocComponentWithVariants
 import org.gradle.api.component.SoftwareComponentFactory
 import org.gradle.api.file.FileCollection
-import org.gradle.api.file.RegularFileProperty
 import org.gradle.api.file.SourceDirectorySet
 import org.gradle.api.provider.Property
 import org.gradle.api.tasks.TaskProvider
@@ -57,7 +56,7 @@ abstract class DefaultApolloExtension(
   internal fun getServiceInfos(project: Project): List<ApolloGradleToolingModel.ServiceInfo> = services.map { service ->
     DefaultServiceInfo(
         name = service.name,
-        schemaFiles = service.lazySchemaFiles(project),
+        schemaFiles = service.schemaFilesSnapshot(project),
         graphqlSrcDirs = service.graphqlSourceDirectorySet.srcDirs,
         upstreamProjects = service.upstreamDependencies.filterIsInstance<ProjectDependency>().map { it.name }.toSet(),
         endpointUrl = service.introspection?.endpointUrl?.orNull,
@@ -362,7 +361,7 @@ abstract class DefaultApolloExtension(
 
     if (service.graphqlSourceDirectorySet.isReallyEmpty) {
       val sourceFolder = service.sourceFolder.getOrElse("")
-      val dir = File(project.projectDir, "src/${mainSourceSet(project)}/graphql/$sourceFolder")
+      val dir = File(project.projectDir, "src/${project.mainSourceSet()}/graphql/$sourceFolder")
 
       service.graphqlSourceDirectorySet.srcDir(dir)
     }
@@ -737,9 +736,8 @@ abstract class DefaultApolloExtension(
       task.group = TASK_GROUP
       task.description = "Generate Apollo schema for service '${service.name}'"
 
-      // This has to be lazy in case the schema is not written yet during configuration
-      // See the `graphql files can be generated by another task` test
-      task.schemaFiles.from(project.provider { service.lazySchemaFiles(project) })
+      task.schemaFiles.from(service.schemaFiles(project))
+      task.fallbackSchemaFiles.from(service.fallbackSchemaFiles(project))
       task.upstreamSchemaFiles.from(schemaConsumerConfiguration)
       task.codegenSchemaOptionsFile.set(optionsTaskProvider.flatMap { it.codegenSchemaOptionsFile })
       task.codegenSchemaFile.set(BuildDirLayout.codegenSchema(project, service))
@@ -828,37 +826,13 @@ abstract class DefaultApolloExtension(
 
       configureBaseCodegenTask(project, task, optionsTaskProvider, service)
 
-      // This has to be lazy in case the schema is not written yet during configuration
-      // See the `graphql files can be generated by another task` test
-      task.schemaFiles.from(project.provider { service.lazySchemaFiles(project) })
+      task.schemaFiles.from(service.schemaFiles(project))
+      task.fallbackSchemaFiles.from(service.fallbackSchemaFiles(project))
       task.codegenSchemaOptionsFile.set(optionsTaskProvider.map { it.codegenSchemaOptionsFile.get() })
       task.irOptionsFile.set(optionsTaskProvider.map { it.irOptionsFile.get() })
     }
   }
 
-  /**
-   * XXX: this returns an absolute path, which might be an issue for the build cache.
-   * I don't think this is much of an issue because tasks like ApolloDownloadSchemaTask don't have any
-   * outputs and are therefore never up-to-date so the build cache will not help much.
-   *
-   * If that ever becomes an issue, making the path relative to the project root might be a good idea.
-   */
-  private fun lazySchemaFileForDownload(service: DefaultService, schemaFile: RegularFileProperty): File {
-    if (schemaFile.isPresent) {
-      return schemaFile.get().asFile
-    }
-
-    val candidates = service.lazySchemaFiles(project)
-    check(candidates.isNotEmpty()) {
-      "No schema files found. Specify introspection.schemaFile or registry.schemaFile"
-    }
-    check(candidates.size == 1) {
-      "Multiple schema files found:\n${candidates.joinToString("\n")}\n\nSpecify introspection.schemaFile or registry.schemaFile"
-    }
-
-    return candidates.single()
-  }
-
   private fun registerDownloadSchemaTasks(service: DefaultService) {
     val introspection = service.introspection
     var taskProvider: TaskProvider<ApolloDownloadSchemaTask>? = null
@@ -868,7 +842,7 @@ abstract class DefaultApolloExtension(
       taskProvider = project.tasks.register(ModelNames.downloadApolloSchemaIntrospection(service), ApolloDownloadSchemaTask::class.java) { task ->
 
         task.group = TASK_GROUP
-        task.outputFile.set(lazySchemaFileForDownload(service, introspection.schemaFile))
+        task.outputFile.set(service.guessSchemaFile(project, introspection.schemaFile))
         task.endpoint.set(introspection.endpointUrl)
         task.header = introspection.headers.get().map { "${it.key}: ${it.value}" }
       }
@@ -879,7 +853,7 @@ abstract class DefaultApolloExtension(
       taskProvider = project.tasks.register(ModelNames.downloadApolloSchemaRegistry(service), ApolloDownloadSchemaTask::class.java) { task ->
 
         task.group = TASK_GROUP
-        task.outputFile.set(lazySchemaFileForDownload(service, registry.schemaFile))
+        task.outputFile.set(service.guessSchemaFile(project, registry.schemaFile))
         task.graph.set(registry.graph)
         task.key.set(registry.key)
         task.graphVariant.set(registry.graphVariant)
@@ -981,38 +955,6 @@ abstract class DefaultApolloExtension(
     private val SourceDirectorySet.isReallyEmpty
       get() = sourceDirectories.isEmpty
 
-    private fun mainSourceSet(project: Project): String {
-      return when (project.extensions.findByName("kotlin")) {
-        is KotlinMultiplatformExtension -> "commonMain"
-        else -> "main"
-      }
-    }
-
-    /**
-     * May return an empty set
-     */
-    fun DefaultService.lazySchemaFiles(project: Project): Set<File> {
-      val files = if (schemaFile.isPresent) {
-        check(schemaFiles.isEmpty) {
-          "Specifying both schemaFile and schemaFiles is an error"
-        }
-        project.files(schemaFile)
-      } else {
-        schemaFiles
-      }
-
-      if (!files.isEmpty) {
-        return files.files
-      }
-
-      return graphqlSourceDirectorySet.srcDirs.flatMap { srcDir ->
-        srcDir.walkTopDown().filter {
-          it.extension in listOf("json", "sdl", "graphqls")
-              && !it.name.startsWith("used") // Avoid detecting the used coordinates as a schema
-        }.toList()
-      }.toSet()
-    }
-
     internal fun Project.hasJavaPlugin() = project.extensions.findByName("java") != null
     internal fun Project.hasKotlinPlugin() = project.extensions.findByName("kotlin") != null
   }

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

@@ -10,6 +10,9 @@ import com.apollographql.apollo3.gradle.api.Service
 import org.gradle.api.Action
 import org.gradle.api.Project
 import org.gradle.api.artifacts.Dependency
+import org.gradle.api.file.ConfigurableFileTree
+import org.gradle.api.file.FileCollection
+import org.gradle.api.file.RegularFileProperty
 import java.io.File
 import javax.inject.Inject
 
@@ -199,3 +202,70 @@ abstract class DefaultService @Inject constructor(val project: Project, override
   internal fun isSchemaModule(): Boolean = upstreamDependencies.isEmpty()
 }
 
+internal fun DefaultService.fallbackFiles(project: Project, block: (ConfigurableFileTree) -> Unit): FileCollection {
+  val fileCollection = project.files()
+
+  graphqlSourceDirectorySet.srcDirs.forEach { directory ->
+    fileCollection.from(project.fileTree(directory, block))
+  }
+
+  return fileCollection
+}
+
+internal fun DefaultService.schemaFiles(project: Project): FileCollection {
+  val fileCollection = project.files()
+
+  if (schemaFile.isPresent) {
+    fileCollection.from(schemaFile)
+  } else {
+    fileCollection.from(schemaFiles)
+  }
+
+  return fileCollection
+}
+
+/**
+ * ConfigurableFileCollections have no way to check for absent vs empty
+ * [schemaFiles] can be empty at configuration time because the task responsible
+ * to create the file did not run yet but still be set (because it will ultimately
+ * create the file)
+ *
+ * The only workaround I found is to pass both to the task and defer the decision
+ * which one to choose to execution time.
+ *
+ * See https://github.com/gradle/gradle/issues/21752
+ */
+internal fun DefaultService.fallbackSchemaFiles(project: Project): FileCollection {
+  return fallbackFiles(project) { configurableFileTree ->
+    configurableFileTree.include(listOf("**/*.graphqls", "**/*.json", "**/*.sdl"))
+  }
+}
+
+/**
+ * Returns a snapshot of the schema files. Some of the schema files might be missing if generated
+ * from another task
+ */
+internal fun DefaultService.schemaFilesSnapshot(project: Project): Set<File> {
+  return schemaFiles(project).files.takeIf { it.isNotEmpty() } ?: fallbackSchemaFiles(project).files
+}
+
+/**
+ * Tries to guess where the schema file is.
+ * This can fail when:
+ * - there are several schema files.
+ * - the schema file is not written yet (because it needs to be written by another task)
+ */
+internal fun DefaultService.guessSchemaFile(project: Project, schemaFile: RegularFileProperty): File {
+  if (schemaFile.isPresent) {
+    return schemaFile.get().asFile
+  }
+  val candidates = schemaFilesSnapshot(project)
+  check(candidates.isNotEmpty()) {
+    "No schema files found. Specify introspection.schemaFile or registry.schemaFile"
+  }
+  check(candidates.size == 1) {
+    "Multiple schema files found:\n${candidates.joinToString("\n")}\n\nSpecify introspection.schemaFile or registry.schemaFile"
+  }
+
+  return candidates.single()
+}

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

@@ -0,0 +1,11 @@
+package com.apollographql.apollo3.gradle.internal
+
+import org.gradle.api.Project
+import org.jetbrains.kotlin.gradle.dsl.KotlinMultiplatformExtension
+
+internal fun Project.mainSourceSet(): String {
+  return when (project.extensions.findByName("kotlin")) {
+    is KotlinMultiplatformExtension -> "commonMain"
+    else -> "main"
+  }
+}