Allow to ignore certain files from the Git repo change detection

pom.xml

@@ -1,12 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
 
     <groupId>com.github.danielflower.mavenplugins</groupId>
     <artifactId>multi-module-maven-release-plugin</artifactId>
-    <version>3.2-SNAPSHOT</version> <!-- When changing also update scaffolding.TestProject.PLUGIN_VERSION_FOR_TESTS and add to src/site/markdown/changelog.md -->
+    <version>3.4-SNAPSHOT</version> <!-- When changing also update scaffolding.TestProject.PLUGIN_VERSION_FOR_TESTS and add to src/site/markdown/changelog.md -->
 
     <name>The Multi Module Maven Release Plugin</name>
     <description>A maven release plugin built for multi-maven-module git repositories allowing continuous deployment
@@ -123,6 +121,15 @@
             <artifactId>maven-invoker</artifactId>
             <version>3.0.1</version>
         </dependency>
+        <dependency>
+            <!--
+            The maven-dependency-plugin wants this to be listed explicitly as it comes as a transitive dependency
+            of maven-model.
+            -->
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-lang3</artifactId>
+            <version>3.4</version>
+        </dependency>
         <dependency>
             <groupId>org.eclipse.jgit</groupId>
             <artifactId>org.eclipse.jgit</artifactId>

src/main/java/com/github/danielflower/mavenplugins/release/AnnotatedTag.java

@@ -28,10 +28,10 @@ private AnnotatedTag(Ref ref, String name, JSONObject message) {
         this.message = message;
     }
 
-    public static AnnotatedTag create(String name, String version, long buildNumber) {
+    public static AnnotatedTag create(String name, String version, String buildNumber) {
         JSONObject message = new JSONObject();
         message.put(VERSION, version);
-        message.put(BUILD_NUMBER, String.valueOf(buildNumber));
+        message.put(BUILD_NUMBER, buildNumber);
         return new AnnotatedTag(null, name, message);
     }
 
@@ -67,8 +67,8 @@ public String version() {
         return String.valueOf(message.get(VERSION));
     }
 
-    public long buildNumber() {
-        return Long.parseLong(String.valueOf(message.get(BUILD_NUMBER)));
+    public String buildNumber() {
+        return String.valueOf(message.get(BUILD_NUMBER));
     }
 
     public Ref saveAtHEAD(Git git) throws GitAPIException {

src/main/java/com/github/danielflower/mavenplugins/release/AnnotatedTagFinder.java

@@ -46,18 +46,12 @@ boolean isPotentiallySameVersionIgnoringBuildNumber(String versionWithoutBuildNu
         return buildNumberOf(versionWithoutBuildNumber, refName) != null;
     }
 
-    Long buildNumberOf(String versionWithoutBuildNumber, String refName) {
+    String buildNumberOf(String versionWithoutBuildNumber, String refName) {
         String tagName = AnnotatedTag.stripRefPrefix(refName);
         String prefix = versionWithoutBuildNumber + versionNamer.getDelimiter();
         if (tagName.startsWith(prefix)) {
-            String end = tagName.substring(prefix.length());
-            try {
-                return Long.parseLong(end);
-            } catch (NumberFormatException e) {
-                return null;
-            }
+            return tagName.substring(prefix.length());
         }
         return null;
     }
-
 }

src/main/java/com/github/danielflower/mavenplugins/release/BaseMojo.java

@@ -1,5 +1,6 @@
 package com.github.danielflower.mavenplugins.release;
 
+import org.apache.commons.lang3.StringUtils;
 import org.apache.maven.artifact.factory.ArtifactFactory;
 import org.apache.maven.artifact.repository.ArtifactRepository;
 import org.apache.maven.artifact.resolver.ArtifactResolver;
@@ -17,15 +18,17 @@
 import org.eclipse.jgit.transport.UsernamePasswordCredentialsProvider;
 
 import java.util.List;
+import java.util.Set;
 
 import static java.lang.String.format;
-import static java.util.Arrays.asList;
 
 /**
  * @author Roland Hauser [email protected]
  *
  */
 public abstract class BaseMojo extends AbstractMojo {
+    private PluginConfiguration pluginConfiguration;
+
 	/**
 	 * The Maven Project.
 	 */
@@ -43,16 +46,37 @@ public abstract class BaseMojo extends AbstractMojo {
 	 * </p>
 	 * <p>
 	 * By default, the plugin will automatically find a suitable build number.
-	 * It will start at version 0 and increment this with each release.
+	 * It will start at 0 and increment this with each release.
 	 * </p>
 	 * <p>
-	 * This can be specified using a command line parameter ("-DbuildNumber=2")
-	 * or in this plugin's configuration.
+	 * This can be specified using a command line parameter (e.g.
+     * <code>-DbuildNumber=2</code>) or in this plugin's configuration.
 	 * </p>
+     * <p>
+     * <strong>null vs. ""</strong>: if you do not define the build number it
+     * is treated as <code>null</code> and the plugin will start at 0. If you
+     * pass an empty string both the build number and the delimiter that
+     * precedes it will be omitted.<br>To define an empty string on the CLI use
+     * <code>-DbuildNumber=''</code>. For the same effect in the POM you can
+     * use <code>&lt;buildNumber&gt;""&lt;/buildNumber&gt;</code> as Maven does
+     * not support empty strings for configuration properties. The plugin will
+     * convert this accordingly.
+     * </p>
 	 */
+	// Maven has historically never supported empty strings in XML plugin configuration (see
+    // http://mail-archives.apache.org/mod_mbox/maven-users/200708.mbox/%[email protected]%3E
+    // from 2007). Hence, if a project defines <buildNumber></buildNumber> the property here will be null. However,
+    // Maven does support -DbuildNumber='' on the CLI.
 	@Parameter(property = "buildNumber")
-	protected Long buildNumber;
+	protected String buildNumber;
 
+    public void setBuildNumber(String buildNumber) {
+        if ("\"\"".equals(buildNumber)) {
+            this.buildNumber = StringUtils.EMPTY;
+        } else {
+            this.buildNumber = buildNumber;
+        }
+    }
 
     /**
      * <p>
@@ -162,6 +186,23 @@ public abstract class BaseMojo extends AbstractMojo {
     @Parameter(property = "arguments")
     public String arguments;
 
+    /**
+     * <p>List of relative file system paths to ignore when detecting changes in the project(s).</p>
+     * <p>The primary purpose is to skip creating new releases if only "infrastructure" files such as
+     * <code>.gitignore</code>, <code>.editorconfig</code> and the like changed. Very basic wild cards are supported as
+     * follows:
+     * <ul>
+     *     <li><code>foo.txt</code> - matches <code>foo.txt</code> in the root of the top-level project</li>
+     *     <li><code>bar/foo.txt</code> - matches <code>foo.txt</code> in the root of the <code>bar</code> directory</li>
+     *     <li><code>bar</code> - matches the <code>foo</code> directory and ignores everything below</li>
+     *     <li><code>**.txt</code> - matches all paths ending in <code>.txt</code> (suffix match)</li>
+     *     <li><code>**.editorconfig</code> - matches all <code>.editorconfig</code> files in all (sub)directories; a special case of suffix matching</li>
+     * <ul/>
+     * <p/>
+     */
+    @Parameter(property = "ignoredPaths")
+    Set<String> ignoredPaths;
+
     final void setSettings(final Settings settings) {
 		this.settings = settings;
 	}
@@ -253,4 +294,53 @@ protected static String getRemoteUrlOrNullIfNoneSet(Scm originalScm, Scm actualS
         return GitHelper.scmUrlToRemote(remote);
     }
 
+    PluginConfiguration getPluginConfiguration() {
+        if (pluginConfiguration == null) {
+            pluginConfiguration = new PluginConfiguration(project, projects, buildNumber, versionNamer,
+                modulesToRelease, modulesToForceRelease, noChangesAction, factory, artifactResolver, remoteRepositories,
+                localRepository, settings, pullTags, arguments, ignoredPaths);
+        }
+        return pluginConfiguration;
+    }
+
+    static class PluginConfiguration {
+        final MavenProject rootProject;
+        final List<MavenProject> projects;
+        final String buildNumber;
+        final VersionNamer versionNamer;
+        final List<String> modulesToRelease;
+        final List<String> modulesToForceRelease;
+        final NoChangesAction noChangesAction;
+        final ArtifactFactory factory;
+        final ArtifactResolver artifactResolver;
+        final List remoteRepositories;
+        final ArtifactRepository localRepository;
+        final Settings settings;
+        final boolean pullTags;
+        final String arguments;
+        final Set<String> ignoredPaths;
+
+        PluginConfiguration(MavenProject rootProject, List<MavenProject> projects, String buildNumber,
+                            VersionNamer versionNamer, List<String> modulesToRelease,
+                            List<String> modulesToForceRelease, NoChangesAction noChangesAction,
+                            ArtifactFactory factory, ArtifactResolver artifactResolver, List remoteRepositories,
+                            ArtifactRepository localRepository, Settings settings, boolean pullTags, String arguments,
+                            Set<String> ignoredPaths) {
+            this.rootProject = rootProject;
+            this.projects = projects;
+            this.buildNumber = buildNumber;
+            this.versionNamer = versionNamer;
+            this.modulesToRelease = modulesToRelease;
+            this.modulesToForceRelease = modulesToForceRelease;
+            this.noChangesAction = noChangesAction;
+            this.factory = factory;
+            this.artifactResolver = artifactResolver;
+            this.remoteRepositories = remoteRepositories;
+            this.localRepository = localRepository;
+            this.settings = settings;
+            this.pullTags = pullTags;
+            this.arguments = arguments;
+            this.ignoredPaths = ignoredPaths;
+        }
+    }
 }

src/main/java/com/github/danielflower/mavenplugins/release/NextMojo.java

@@ -45,8 +45,8 @@ public void execute() throws MojoExecutionException, MojoFailureException {
                                                           project.getModel().getScm()))
                 .credentialsProvider(getCredentialsProvider(log))
                 .buildFromCurrentDir();
-            ResolverWrapper resolverWrapper = new ResolverWrapper(factory, artifactResolver, remoteRepositories, localRepository);
-            Reactor reactor = Reactor.fromProjects(log, repo, project, projects, buildNumber, modulesToForceRelease, noChangesAction, resolverWrapper, versionNamer);
+            ResolverWrapper resolverWrapper = new ResolverWrapper(getPluginConfiguration());
+            Reactor reactor = Reactor.fromProjects(repo, getPluginConfiguration(), resolverWrapper, noChangesAction, log);
             if (reactor == null) {
                 return;
             }

src/main/java/com/github/danielflower/mavenplugins/release/Reactor.java

@@ -1,5 +1,6 @@
 package com.github.danielflower.mavenplugins.release;
 
+import org.apache.commons.lang3.StringUtils;
 import org.apache.maven.model.Dependency;
 import org.apache.maven.plugin.MojoExecutionException;
 import org.apache.maven.plugin.logging.Log;
@@ -28,31 +29,32 @@ public List<ReleasableModule> getModulesInBuildOrder() {
         return modulesInBuildOrder;
     }
 
-    public static Reactor fromProjects(Log log, LocalGitRepo gitRepo, MavenProject rootProject, List<MavenProject> projects, Long buildNumber, List<String> modulesToForceRelease, NoChangesAction actionWhenNoChangesDetected, ResolverWrapper resolverWrapper, VersionNamer versionNamer) throws ValidationException, GitAPIException, MojoExecutionException {
-        DiffDetector detector = new TreeWalkingDiffDetector(gitRepo.git.getRepository());
-        List<ReleasableModule> modules = new ArrayList<ReleasableModule>();
+    static Reactor fromProjects(LocalGitRepo gitRepo, BaseMojo.PluginConfiguration pluginConfiguration, ResolverWrapper resolverWrapper, NoChangesAction noChangesAction, Log log) throws ValidationException, GitAPIException, MojoExecutionException {
+        DiffDetector detector = new TreeWalkingDiffDetector(gitRepo.git.getRepository(), pluginConfiguration.ignoredPaths);
+        List<ReleasableModule> modules = new ArrayList<>();
 
-        resolveVersionsDefinedThroughProperties(projects);
+        resolveVersionsDefinedThroughProperties(pluginConfiguration.projects);
 
+        VersionNamer versionNamer = pluginConfiguration.versionNamer;
         AnnotatedTagFinder annotatedTagFinder = new AnnotatedTagFinder(versionNamer);
-        for (MavenProject project : projects) {
-            String relativePathToModule = calculateModulePath(rootProject, project);
+        for (MavenProject project : pluginConfiguration.projects) {
+            String relativePathToModule = calculateModulePath(pluginConfiguration.rootProject, project);
             String artifactId = project.getArtifactId();
             String versionWithoutBuildNumber = project.getVersion().replace("-SNAPSHOT", "");
             List<AnnotatedTag> previousTagsForThisModule = annotatedTagFinder.tagsForVersion(gitRepo.git, artifactId, versionWithoutBuildNumber);
 
 
-            Collection<Long> previousBuildNumbers = new ArrayList<Long>();
+            Collection<String> previousBuildNumbers = new ArrayList<>();
             if (previousTagsForThisModule != null) {
                 for (AnnotatedTag previousTag : previousTagsForThisModule) {
                     previousBuildNumbers.add(previousTag.buildNumber());
                 }
             }
 
-            Collection<Long> remoteBuildNumbers = getRemoteBuildNumbers(gitRepo, artifactId, versionWithoutBuildNumber, versionNamer);
+            Collection<String> remoteBuildNumbers = getRemoteBuildNumbers(gitRepo, artifactId, versionWithoutBuildNumber, versionNamer);
             previousBuildNumbers.addAll(remoteBuildNumbers);
 
-            VersionName newVersion = versionNamer.name(project.getVersion(), buildNumber, previousBuildNumbers);
+            VersionName newVersion = versionNamer.name(project.getVersion(), pluginConfiguration.buildNumber, previousBuildNumbers);
 
             boolean oneOfTheDependenciesHasChanged = false;
             String changedDependency = null;
@@ -89,7 +91,7 @@ public static Reactor fromProjects(Log log, LocalGitRepo gitRepo, MavenProject r
 
             String equivalentVersion = null;
 
-            if(modulesToForceRelease != null && modulesToForceRelease.contains(artifactId)) {
+            if(pluginConfiguration.modulesToForceRelease != null && pluginConfiguration.modulesToForceRelease.contains(artifactId)) {
                 log.info("Releasing " + artifactId + " " + newVersion.releaseVersion() + " as we was asked to forced release.");
             } else if (oneOfTheDependenciesHasChanged) {
                 log.info("Releasing " + artifactId + " " + newVersion.releaseVersion() + " as " + changedDependency + " has changed.");
@@ -113,15 +115,15 @@ public static Reactor fromProjects(Log log, LocalGitRepo gitRepo, MavenProject r
         }
 
         if (!atLeastOneBeingReleased(modules)) {
-            switch (actionWhenNoChangesDetected) {
+            switch (noChangesAction) {
                 case ReleaseNone:
                     log.warn("No changes have been detected in any modules so will not perform release");
                     return null;
                 case FailBuild:
                     throw new MojoExecutionException("No module changes have been detected");
                 default:
                     log.warn("No changes have been detected in any modules so will re-release them all");
-                    List<ReleasableModule> newList = new ArrayList<ReleasableModule>();
+                    List<ReleasableModule> newList = new ArrayList<>();
                     for (ReleasableModule module : modules) {
                         newList.add(module.createReleasableVersion());
                     }
@@ -145,14 +147,14 @@ private static boolean hasSameMavenGAByDependencyLocation(ReleasableModule modul
         return modelId[0].equals(module.getGroupId()) && modelId[1].equals(module.getArtifactId());
     }
 
-    private static Collection<Long> getRemoteBuildNumbers(LocalGitRepo gitRepo, String artifactId, String versionWithoutBuildNumber, VersionNamer versionNamer) throws GitAPIException {
+    private static Collection<String> getRemoteBuildNumbers(LocalGitRepo gitRepo, String artifactId, String versionWithoutBuildNumber, VersionNamer versionNamer) throws GitAPIException {
         Collection<Ref> remoteTagRefs = gitRepo.allTags();
-        Collection<Long> remoteBuildNumbers = new ArrayList<Long>();
+        Collection<String> remoteBuildNumbers = new ArrayList<>();
         String tagWithoutBuildNumber = artifactId + "-" + versionWithoutBuildNumber;
         AnnotatedTagFinder annotatedTagFinder = new AnnotatedTagFinder(versionNamer);
         for (Ref remoteTagRef : remoteTagRefs) {
             String remoteTagName = remoteTagRef.getName();
-            Long buildNumber = annotatedTagFinder.buildNumberOf(tagWithoutBuildNumber, remoteTagName);
+            String buildNumber = annotatedTagFinder.buildNumberOf(tagWithoutBuildNumber, remoteTagName);
             if (buildNumber != null) {
                 remoteBuildNumbers.add(buildNumber);
             }
@@ -190,20 +192,25 @@ static AnnotatedTag hasChangedSinceLastRelease(List<AnnotatedTag> previousTagsFo
         try {
             if (previousTagsForThisModule.size() == 0) return null;
             boolean hasChanged = detector.hasChangedSince(relativePathToModule, project.getModel().getModules(), previousTagsForThisModule);
-            return hasChanged ? null : tagWithHighestBuildNumber(previousTagsForThisModule);
+            return hasChanged ? null : findTagWithHighestBuildNumber(previousTagsForThisModule);
         } catch (Exception e) {
             throw new MojoExecutionException("Error while detecting whether or not " + project.getArtifactId() + " has changed since the last release", e);
         }
     }
 
-    private static AnnotatedTag tagWithHighestBuildNumber(List<AnnotatedTag> tags) {
-        AnnotatedTag cur = null;
+    // Ignores any tags with non-numeric build numbers and finds the one with the largest build number among the others.
+    // The tags are guaranteed to be for the same /business version/ i.e. it's likely a small list.
+    private static AnnotatedTag findTagWithHighestBuildNumber(List<AnnotatedTag> tags) {
+        AnnotatedTag tagWithHighestBuildNumber = null;
         for (AnnotatedTag tag : tags) {
-            if (cur == null || tag.buildNumber() > cur.buildNumber()) {
-                cur = tag;
+            if(StringUtils.isNumeric(tag.buildNumber())) {
+                if (tagWithHighestBuildNumber == null ||
+                    Long.parseLong(tag.buildNumber()) > Long.parseLong(tagWithHighestBuildNumber.buildNumber())) {
+                    tagWithHighestBuildNumber = tag;
+                }
             }
         }
-        return cur;
+        return tagWithHighestBuildNumber;
     }
 
     public ReleasableModule findByLabel(String label) {

src/main/java/com/github/danielflower/mavenplugins/release/ReleasableModule.java

@@ -44,7 +44,7 @@ public String getVersion() {
         return version.businessVersion();
     }
 
-    public long getBuildNumber() {
+    public String getBuildNumber() {
         return version.buildNumber();
     }
 

src/main/java/com/github/danielflower/mavenplugins/release/ReleaseMojo.java

@@ -123,8 +123,8 @@ public void execute() throws MojoExecutionException, MojoFailureException {
                 .buildFromCurrentDir();
             repo.errorIfNotClean();
 
-            ResolverWrapper resolverWrapper = new ResolverWrapper(factory, artifactResolver, remoteRepositories, localRepository);
-            Reactor reactor = Reactor.fromProjects(log, repo, project, projects, buildNumber, modulesToForceRelease, noChangesAction, resolverWrapper, versionNamer);
+            ResolverWrapper resolverWrapper = new ResolverWrapper(getPluginConfiguration());
+            Reactor reactor = Reactor.fromProjects(repo, getPluginConfiguration(), resolverWrapper, noChangesAction, log);
             if (reactor == null) {
                 return;
             }