Setup jacoco (#60)

all/README.md

@@ -0,0 +1 @@
+This is a utility project which depends on all other projects in this repository. We use it for global checks, for example collecting all coverage reports from all modules for uploading to codecov.

all/build.gradle.kts

@@ -0,0 +1,68 @@
+plugins {
+    id("otel.java-conventions")
+}
+
+description = "OpenTelemetry Contrib Testing"
+
+dependencies {
+    rootProject.subprojects.forEach { subproject ->
+        // Generate aggregate coverage report for published modules that enable jacoco.
+        subproject.plugins.withId("jacoco") {
+            subproject.plugins.withId("maven-publish") {
+                implementation(project(subproject.path)) {
+                    isTransitive = false
+                }
+            }
+        }
+    }
+}
+
+// https://docs.gradle.org/current/samples/sample_jvm_multi_project_with_code_coverage.html
+
+val sourcesPath by configurations.creating {
+    isVisible = false
+    isCanBeResolved = true
+    isCanBeConsumed = false
+    extendsFrom(configurations.implementation.get())
+    attributes {
+        attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
+        attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
+        attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("source-folders"))
+    }
+}
+
+val coverageDataPath by configurations.creating {
+    isVisible = false
+    isCanBeResolved = true
+    isCanBeConsumed = false
+    extendsFrom(configurations.implementation.get())
+    attributes {
+        attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
+        attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
+        attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("jacoco-coverage-data"))
+    }
+}
+
+tasks.named<JacocoReport>("jacocoTestReport") {
+    enabled = true
+
+    configurations.runtimeClasspath.get().forEach {
+        additionalClassDirs(zipTree(it).filter {
+            // Exclude mrjar (jacoco complains), shaded, and generated code
+            !it.absolutePath.contains("META-INF/versions/") &&
+                    !it.absolutePath.contains("AutoValue_")
+        })
+    }
+    additionalSourceDirs(sourcesPath.incoming.artifactView { lenient(true) }.files)
+    executionData(coverageDataPath.incoming.artifactView { lenient(true) }.files.filter { it.exists() })
+
+    reports {
+        // xml is usually used to integrate code coverage with
+        // other tools like SonarQube, Coveralls or Codecov
+        xml.required.set(true)
+
+        // HTML reports can be used to see code coverage
+        // without any external tools
+        html.required.set(true)
+    }
+}

buildSrc/src/main/kotlin/otel.jacoco-conventions.gradle.kts

@@ -0,0 +1,49 @@
+plugins {
+    `java-library`
+
+    jacoco
+}
+
+// https://docs.gradle.org/current/samples/sample_jvm_multi_project_with_code_coverage.html
+
+// Do not generate reports for individual projects
+tasks.named("jacocoTestReport") {
+    enabled = false
+}
+
+configurations {
+    val implementation by getting
+
+    create("transitiveSourceElements") {
+        isVisible = false
+        isCanBeResolved = false
+        isCanBeConsumed = true
+        extendsFrom(implementation)
+        attributes {
+            attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
+            attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
+            attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("source-folders"))
+        }
+        sourceSets.main.get().java.srcDirs.forEach {
+            outgoing.artifact(it)
+        }
+    }
+
+    create("coverageDataElements") {
+        isVisible = false
+        isCanBeResolved = false
+        isCanBeConsumed = true
+        extendsFrom(implementation)
+        attributes {
+            attribute(Usage.USAGE_ATTRIBUTE, objects.named(Usage.JAVA_RUNTIME))
+            attribute(Category.CATEGORY_ATTRIBUTE, objects.named(Category.DOCUMENTATION))
+            attribute(DocsType.DOCS_TYPE_ATTRIBUTE, objects.named("jacoco-coverage-data"))
+        }
+        // This will cause the test task to run if the coverage data is requested by the aggregation task
+        // The tasks must be eagerly evaluated (no configureEach) to ensure jacoco is wired up
+        // correctly.
+        tasks.withType<Test>() {
+            outgoing.artifact(the<JacocoTaskExtension>().destinationFile!!)
+        }
+    }
+}

buildSrc/src/main/kotlin/otel.java-conventions.gradle.kts

@@ -3,6 +3,7 @@ import org.gradle.api.tasks.testing.logging.TestExceptionFormat
 plugins {
     `java-library`
 
+    id("otel.jacoco-conventions")
     id("otel.spotless-conventions")
 }
 

settings.gradle.kts

@@ -16,6 +16,7 @@ dependencyResolutionManagement {
 
 rootProject.name = "opentelemetry-java-contrib"
 
+include(":all")
 include(":aws-xray")
 include(":dependencyManagement")
 include(":example")