review

Author: rmannibucau

src/main/java/org/apache/maven/plugins/dependency/fromDependencies/RenderDependenciesMojo.java

@@ -28,6 +28,7 @@
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
@@ -49,6 +50,7 @@
 import org.apache.maven.project.MavenProjectHelper;
 import org.apache.maven.project.ProjectBuilder;
 import org.apache.maven.shared.artifact.filter.collection.ArtifactsFilter;
+import org.apache.velocity.Template;
 import org.apache.velocity.VelocityContext;
 import org.apache.velocity.app.VelocityEngine;
 import org.apache.velocity.tools.generic.CollectionTool;
@@ -59,37 +61,45 @@
 /**
  * This goal renders dependencies based on a velocity template.
  *
- * @since 3.8.2
+ * @since 3.9.0
  */
 @Mojo(
         name = "render-dependencies",
         requiresDependencyResolution = ResolutionScope.TEST,
         defaultPhase = LifecyclePhase.GENERATE_SOURCES,
         threadSafe = true)
 public class RenderDependenciesMojo extends AbstractDependencyFilterMojo {
+    /**
+     * Encoding to write the rendered template.
+     * @since 3.9.0
+     */
     @Parameter(property = "outputEncoding", defaultValue = "${project.reporting.outputEncoding}")
     private String outputEncoding;
 
     /**
      * The file to write the rendered template string. If undefined, it just prints the classpath as [INFO].
+     * @since 3.9.0
      */
     @Parameter(property = "mdep.outputFile")
     private File outputFile;
 
     /**
      * If not null or empty it will attach the artifact with this classifier.
+     * @since 3.9.0
      */
     @Parameter(property = "mdep.classifier", defaultValue = "template")
     private String classifier;
 
     /**
      * Extension to use for the attached file if classifier is not null/empty.
+     * @since 3.9.0
      */
     @Parameter(property = "mdep.extension", defaultValue = "txt")
     private String extension;
 
     /**
      * velocity template to use to render the output file.
+     * @since 3.9.0
      */
     @Parameter(property = "mdep.template", defaultValue = "<set the template>")
     private String template;
@@ -148,8 +158,16 @@ protected void doExecute() throws MojoExecutionException {
      * @return the template rendered.
      */
     private String render(final List<Artifact> artifacts) {
+        final Path templatePath = getTemplatePath();
+        final boolean fromFile = templatePath != null && Files.exists(templatePath);
+
         final Properties props = new Properties();
         props.setProperty("runtime.strict_mode.enable", "true");
+        if (fromFile) {
+            props.setProperty(
+                    "resource.loader.file.path",
+                    templatePath.toAbsolutePath().getParent().toString());
+        }
 
         final VelocityEngine ve = new VelocityEngine(props);
         ve.init();
@@ -160,19 +178,29 @@ private String render(final List<Artifact> artifacts) {
 
         // Merge template + context
         final StringWriter writer = new StringWriter();
-        try {
-            ve.evaluate(context, writer, "tpl-" + Math.abs(hashCode()), template);
-        } finally {
-            try {
-                writer.close();
-            } catch (final IOException e) {
-                // no-op, not possible
+        try (final StringWriter ignored = writer) {
+            if (fromFile) {
+                final Template template =
+                        ve.getTemplate(templatePath.getFileName().toString());
+                template.merge(context, writer);
+            } else {
+                ve.evaluate(context, writer, "tpl-" + Math.abs(hashCode()), template);
             }
+        } catch (final IOException e) {
+            // no-op, not possible
         }
 
         return writer.toString();
     }
 
+    private Path getTemplatePath() {
+        try {
+            return Paths.get(template);
+        } catch (final RuntimeException re) {
+            return null;
+        }
+    }
+
     /**
      * Trivial null protection impl for comparing callback.
      * @param getter nominal getter.
@@ -227,6 +255,10 @@ protected ArtifactsFilter getMarkedArtifactFilter() {
         return null;
     }
 
+    public void setExtension(final String extension) {
+        this.extension = extension;
+    }
+
     public void setOutputEncoding(final String outputEncoding) {
         this.outputEncoding = outputEncoding;
     }

src/test/java/org/apache/maven/plugins/dependency/fromDependencies/TestRenderDependenciesMojo.java

@@ -19,6 +19,9 @@
 package org.apache.maven.plugins.dependency.fromDependencies;
 
 import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
 import java.util.Set;
 
 import org.apache.maven.artifact.Artifact;
@@ -66,12 +69,7 @@ protected void setUp() throws Exception {
     public void testRender() throws Exception {
         final File rendered = new File(testDir, "render-dependencies.testRender.txt");
 
-        final MavenProject project = mojo.getProject();
-        final Set<Artifact> artifacts = stubFactory.getScopedArtifacts();
-        final Set<Artifact> directArtifacts = stubFactory.getReleaseAndSnapshotArtifacts();
-        artifacts.addAll(directArtifacts);
-        project.setArtifacts(artifacts);
-        project.setDependencyArtifacts(directArtifacts);
+        setupProject();
 
         mojo.setTemplate("deps:\n"
                 + "  jars:\n"
@@ -101,4 +99,51 @@ public void testRender() throws Exception {
                         + "  - local:///opt/test/libs/system-1.0.jar\n"
                         + "  - local:///opt/test/libs/test-1.0.jar\n");
     }
+
+    /**
+     * Tests the rendering with a file template.
+     */
+    public void testRenderFromFile() throws Exception {
+        final File rendered = new File(testDir, "render-dependencies.testRenderFromFile.txt");
+        final File template = new File(testDir, "render-dependencies.testRenderFromFile.template.vm");
+        Files.write(
+                template.toPath(),
+                ("deps:\n"
+                                + "  jars:\n"
+                                + "  - local:///opt/test/libs/compile-1.0.jar\n"
+                                + "  - local:///opt/test/libs/provided-1.0.jar\n"
+                                + "  - local:///opt/test/libs/release-1.0.jar\n"
+                                + "  - local:///opt/test/libs/runtime-1.0.jar\n"
+                                + "  - local:///opt/test/libs/snapshot-2.0-SNAPSHOT.jar\n"
+                                + "  - local:///opt/test/libs/system-1.0.jar\n"
+                                + "  - local:///opt/test/libs/test-1.0.jar\n")
+                        .getBytes(StandardCharsets.UTF_8));
+
+        setupProject();
+
+        mojo.setTemplate(template.getAbsolutePath());
+        mojo.setOutputFile(rendered);
+        mojo.execute();
+
+        assertThat(rendered)
+                .content()
+                .isEqualTo("deps:\n"
+                        + "  jars:\n"
+                        + "  - local:///opt/test/libs/compile-1.0.jar\n"
+                        + "  - local:///opt/test/libs/provided-1.0.jar\n"
+                        + "  - local:///opt/test/libs/release-1.0.jar\n"
+                        + "  - local:///opt/test/libs/runtime-1.0.jar\n"
+                        + "  - local:///opt/test/libs/snapshot-2.0-SNAPSHOT.jar\n"
+                        + "  - local:///opt/test/libs/system-1.0.jar\n"
+                        + "  - local:///opt/test/libs/test-1.0.jar\n");
+    }
+
+    private void setupProject() throws IOException {
+        final MavenProject project = mojo.getProject();
+        final Set<Artifact> artifacts = stubFactory.getScopedArtifacts();
+        final Set<Artifact> directArtifacts = stubFactory.getReleaseAndSnapshotArtifacts();
+        artifacts.addAll(directArtifacts);
+        project.setArtifacts(artifacts);
+        project.setDependencyArtifacts(directArtifacts);
+    }
 }