feat(Maven): Add more error handling for Tycho

Create issues for build failures and for projects for which no
dependency information could be retrieved.

Signed-off-by: Oliver Heger <oliver.heger@bosch.io>

Author: oheger-bosch

plugins/package-managers/maven/src/main/kotlin/Tycho.kt

@@ -45,6 +45,7 @@ import org.ossreviewtoolkit.model.Issue
 import org.ossreviewtoolkit.model.ProjectAnalyzerResult
 import org.ossreviewtoolkit.model.config.AnalyzerConfiguration
 import org.ossreviewtoolkit.model.config.RepositoryConfiguration
+import org.ossreviewtoolkit.model.createAndLogIssue
 import org.ossreviewtoolkit.model.utils.DependencyGraphBuilder
 import org.ossreviewtoolkit.plugins.packagemanagers.maven.utils.DependencyTreeLogger
 import org.ossreviewtoolkit.plugins.packagemanagers.maven.utils.LocalProjectWorkspaceReader
@@ -90,8 +91,7 @@ class Tycho(
         logger.info { "Resolving Tycho dependencies for $definitionFile." }
 
         val collector = TychoProjectsCollector()
-        val (_, buildLog) = runBuild(collector, definitionFile.parentFile)
-        // TODO: Create issues for a failed build and projects for which dependencies could not be resolved.
+        val (exitCode, buildLog) = runBuild(collector, definitionFile.parentFile)
 
         val resolvedProjects = createMavenSupport(collector).use { mavenSupport ->
             graphBuilder = createGraphBuilder(mavenSupport, collector.mavenProjects)
@@ -107,8 +107,11 @@ class Tycho(
 
         buildLog.delete()
 
-        // Assign issues that are global to the build to the root project.
-        val rootIssues = mutableListOf<Issue>()
+        val rootProject = collector.mavenProjects.values.find { it.file == definitionFile }
+            ?: throw TychoBuildException("Tycho root project could not be built.")
+
+        val rootIssues = createRootIssues(exitCode, collector, resolvedProjects)
+
         graphBuilder.packages().createIssuesForAutoGeneratedPoms(managerName, rootIssues)
 
         return resolvedProjects.map { mavenProject ->
@@ -119,7 +122,7 @@ class Tycho(
                 mavenProject.file.parentFile,
                 graphBuilder.scopesFor(projectId)
             )
-            val issues = rootIssues.takeIf { mavenProject.file == definitionFile } ?: emptyList()
+            val issues = rootIssues.takeIf { mavenProject == rootProject }.orEmpty()
             ProjectAnalyzerResult(project, emptySet(), issues)
         }
     }
@@ -223,11 +226,50 @@ class Tycho(
             graphBuilder.addDependency(DependencyGraph.qualifyScope(projectId, node.dependency.scope), node)
         }
     }
+
+    /**
+     * Create a list with [Issue]s for global build problems. Since this implementation executes a single
+     * multi-module build, it is typically not possible to assign single issues to specific projects. Therefore, all
+     * issues are assigned to the root project. In order to generate the issues, evaluate the [exitCode] of the Maven
+     * build, the projects found by the [collector], and the [resolvedProjects] for which dependency information was
+     * found.
+     */
+    private fun createRootIssues(
+        exitCode: Int,
+        collector: TychoProjectsCollector,
+        resolvedProjects: List<MavenProject>
+    ): MutableList<Issue> {
+        val rootIssues = mutableListOf<Issue>()
+        if (exitCode != 0) {
+            rootIssues += createAndLogIssue(
+                managerName,
+                "Maven build failed with non-zero exit code $exitCode."
+            )
+        }
+
+        val missingProjects = collector.mavenProjects.keys - resolvedProjects.mapTo(mutableSetOf()) { it.internalId }
+
+        missingProjects.forEach { projectId ->
+            val coordinates = collector.mavenProjects.getValue(projectId).identifier(projectType).toCoordinates()
+            rootIssues += createAndLogIssue(
+                managerName,
+                "No dependency information found for project '$coordinates'. " +
+                    "This may be caused by a build failure."
+            )
+        }
+
+        return rootIssues
+    }
 }
 
 /** The name of the logger used by the Maven dependency tree plugin. */
 private const val DEPENDENCY_TREE_LOGGER = "org.apache.maven.plugins.dependency.tree.TreeMojo"
 
+/**
+ * A special exception class to indicate that a Tycho build failed completely.
+ */
+class TychoBuildException(message: String, cause: Throwable? = null) : Exception(message, cause)
+
 /**
  * An internal helper class that gets registered as a Maven lifecycle participant to obtain all [MavenProject]s
  * encountered during the build.

plugins/package-managers/maven/src/test/kotlin/TychoTest.kt

@@ -19,10 +19,12 @@
 
 package org.ossreviewtoolkit.plugins.packagemanagers.maven
 
+import io.kotest.assertions.throwables.shouldThrow
 import io.kotest.core.TestConfiguration
 import io.kotest.core.spec.style.WordSpec
 import io.kotest.engine.spec.tempdir
 import io.kotest.engine.spec.tempfile
+import io.kotest.inspectors.forAll
 import io.kotest.matchers.collections.beEmpty
 import io.kotest.matchers.collections.shouldContainExactlyInAnyOrder
 import io.kotest.matchers.should
@@ -48,6 +50,7 @@ import org.ossreviewtoolkit.model.Severity
 import org.ossreviewtoolkit.model.utils.DependencyGraphBuilder
 import org.ossreviewtoolkit.plugins.packagemanagers.maven.utils.DependencyTreeMojoNode
 import org.ossreviewtoolkit.plugins.packagemanagers.maven.utils.JSON
+import org.ossreviewtoolkit.plugins.packagemanagers.maven.utils.identifier
 
 class TychoTest : WordSpec({
     "mapDefinitionFiles()" should {
@@ -116,6 +119,73 @@ class TychoTest : WordSpec({
 
             subResults.single().issues should beEmpty()
         }
+
+        "throw an exception if the root project could not be built" {
+            val definitionFile = tempfile()
+            val rootProject = createMavenProject("root", definitionFile)
+            val subProject1 = createMavenProject("sub1")
+            val subProject2 = createMavenProject("sub2")
+
+            val buildOutput = listOf(subProject2, rootProject, subProject1).toJson()
+
+            val tycho = spyk(Tycho("Tycho", tempdir(), mockk(relaxed = true), mockk(relaxed = true)))
+            injectCliMock(tycho, buildOutput, listOf(subProject1, subProject2))
+
+            val exception = shouldThrow<TychoBuildException> {
+                tycho.resolveDependencies(definitionFile, emptyMap())
+            }
+
+            exception.message shouldContain "Tycho root project could not be built."
+        }
+
+        "generate an issue if the Maven build had a non-zero exit code" {
+            val definitionFile = tempfile()
+            val rootProject = createMavenProject("root", definitionFile)
+            val subProject = createMavenProject("sub")
+            val projectsList = listOf(rootProject, subProject)
+
+            val tycho = spyk(Tycho("Tycho", tempdir(), mockk(relaxed = true), mockk(relaxed = true)))
+            injectCliMock(tycho, projectsList.toJson(), projectsList, exitCode = 1)
+
+            val results = tycho.resolveDependencies(definitionFile, emptyMap())
+
+            val rootResults = results.single { it.project.id.name == "root" }
+            with(rootResults.issues.single()) {
+                severity shouldBe Severity.ERROR
+                message shouldContain "Maven build failed"
+                source shouldBe "Tycho"
+            }
+        }
+
+        "generate issues for sub projects that do not occur in the build output" {
+            val definitionFile = tempfile()
+            val rootProject = createMavenProject("root", definitionFile)
+            val subProject1 = createMavenProject("sub1")
+            val subProject2 = createMavenProject("sub2")
+            val subProject3 = createMavenProject("sub3")
+            val projectsList = listOf(rootProject, subProject1, subProject2, subProject3)
+
+            val tycho = spyk(Tycho("Tycho", tempdir(), mockk(relaxed = true), mockk(relaxed = true)))
+            injectCliMock(tycho, projectsList.take(2).toJson(), projectsList, exitCode = 1)
+
+            val results = tycho.resolveDependencies(definitionFile, emptyMap())
+
+            val rootResults = results.single { it.project.id.name == "root" }
+            rootResults.issues.forAll { issue ->
+                issue.source shouldBe "Tycho"
+                issue.severity shouldBe Severity.ERROR
+            }
+
+            val regExBuildProjectError = Regex(".*for project '(.*)'.*")
+            val projectIssues = rootResults.issues.mapNotNull { issue ->
+                regExBuildProjectError.matchEntire(issue.message)?.groupValues?.get(1)
+            }
+
+            projectIssues shouldContainExactlyInAnyOrder listOf(
+                subProject2.identifier("Tycho").toCoordinates(),
+                subProject3.identifier("Tycho").toCoordinates()
+            )
+        }
     }
 })