add goal to create and attach bom checksums

pom.xml

@@ -12,7 +12,7 @@
 
     <groupId>de.eitco.cicd</groupId>
     <artifactId>bom-maven-plugin</artifactId>
-    <version>5.0.1-SNAPSHOT</version>
+    <version>5.1.0-SNAPSHOT</version>
     <packaging>maven-plugin</packaging>
 
     <developers>

src/main/java/de/eitco/cicd/bom/AbstractBillOfMaterialsMojo.java

@@ -41,16 +41,21 @@ public abstract class AbstractBillOfMaterialsMojo extends AbstractMojo {
 
     protected Artifact makeBomArtifact() {
 
-        Artifact result = artifactFactory.createArtifactWithClassifier(groupId, artifactId, version, "pom", null);
+        Artifact result = makeArtifact("pom");
 
         result.setFile(targetFile);
 
         return result;
     }
 
+    protected Artifact makeArtifact(String extension) {
+
+        return artifactFactory.createArtifactWithClassifier(groupId, artifactId, version, extension, null);
+    }
+
     protected Artifact makeSignatureArtifact() {
 
-        Artifact result = artifactFactory.createArtifactWithClassifier(groupId, artifactId, version, "pom" + signatureExtension, null);
+        Artifact result = makeArtifact("pom" + signatureExtension);
 
         result.setFile(makeSignatureFile());
 

src/main/java/de/eitco/cicd/bom/CreateBomChecksumsMojo.java

@@ -0,0 +1,50 @@
+package de.eitco.cicd.bom;
+
+import org.apache.maven.artifact.Artifact;
+import org.apache.maven.plugin.MojoExecutionException;
+import org.apache.maven.plugin.install.DualDigester;
+import org.apache.maven.plugins.annotations.LifecyclePhase;
+import org.apache.maven.plugins.annotations.Mojo;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+
+@Mojo(name = "checksums", defaultPhase = LifecyclePhase.PROCESS_SOURCES)
+public class CreateBomChecksumsMojo extends AbstractBillOfMaterialsMojo {
+
+    private final DualDigester digester = new DualDigester();
+
+    @Override
+    public void execute() throws MojoExecutionException {
+
+        File bomFile = makeBomArtifact().getFile();
+
+        digester.calculate(bomFile);
+
+        attachChecksum(bomFile, ".md5", digester.getMd5());
+        attachChecksum(bomFile, ".sha1", digester.getSha1());
+    }
+
+    private void attachChecksum(File bomFile, String extension, String checksum) throws MojoExecutionException {
+
+        try {
+
+            File checksumFile = new File(bomFile.getAbsolutePath() + extension);
+
+            Files.writeString(checksumFile.toPath(), checksum);
+
+            Artifact artifact = makeArtifact("pom" + extension);
+
+            artifact.setFile(checksumFile);
+            project.addAttachedArtifact(artifact);
+
+        } catch (IOException e) {
+
+            throw new MojoExecutionException(e);
+        }
+
+    }
+
+
+}