git-commit-id#365 set ahead and behind properties

src/main/java/pl/project13/maven/git/AheadBehind.java

@@ -0,0 +1,60 @@
+package pl.project13.maven.git;
+
+import java.util.Objects;
+
+public class AheadBehind {
+
+  public static final AheadBehind NO_REMOTE = AheadBehind.of("NO_REMOTE", "NO_REMOTE");
+
+  private final String ahead;
+
+  private final String behind;
+
+  private AheadBehind(String ahead, String behind) {
+    this.ahead = ahead;
+    this.behind = behind;
+  }
+
+  public static AheadBehind of(int ahead, int behind) {
+    return new AheadBehind(String.valueOf(ahead), String.valueOf(behind));
+  }
+
+  public static AheadBehind of(String ahead, String behind) {
+    return new AheadBehind(ahead, behind);
+  }
+
+  public String ahead() {
+    return ahead;
+  }
+
+  public String behind() {
+    return behind;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(ahead, behind);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (this == obj) {
+      return true;
+    }
+    if (obj == null) {
+      return false;
+    }
+    if (getClass() != obj.getClass()) {
+      return false;
+    }
+    AheadBehind other = (AheadBehind) obj;
+
+    if (!Objects.equals(ahead, other.ahead)) {
+      return false;
+    }
+    if (!Objects.equals(behind, other.behind)) {
+      return false;
+    }
+    return true;
+  }
+}

src/main/java/pl/project13/maven/git/GitCommitPropertyConstant.java

@@ -3,6 +3,8 @@
 public class GitCommitPropertyConstant {
   // these properties will be exposed to maven
   public static final String BRANCH = "branch";
+  public static final String BRANCH_AHEAD = "branch.ahead";
+  public static final String BRANCH_BEHIND = "branch.behind";
   public static final String DIRTY = "dirty";
   // only one of the following two will be exposed, depending on the commitIdGenerationMode
   public static final String COMMIT_ID_FLAT = "commit.id";

src/main/java/pl/project13/maven/git/GitDataProvider.java

@@ -149,6 +149,13 @@ public void loadGitData(@Nonnull String evaluateOnCommit, @Nonnull Properties pr
       put(properties,GitCommitPropertyConstant.CLOSEST_TAG_COMMIT_COUNT, getClosestTagCommitCount());
 
       put(properties,GitCommitPropertyConstant.TOTAL_COMMIT_COUNT, getTotalCommitCount());
+      try {
+        AheadBehind aheadBehind = getAheadBehind();
+        put(properties, GitCommitPropertyConstant.BRANCH_AHEAD, aheadBehind.ahead());
+        put(properties, GitCommitPropertyConstant.BRANCH_BEHIND, aheadBehind.behind());  
+      } catch (Exception e) {
+        log.error("Failed to read ahead behind", e);
+      }
     } finally {
       finalCleanUp();
     }

src/main/java/pl/project13/maven/git/GitProvider.java

@@ -40,5 +40,7 @@ public interface GitProvider {
   String getTotalCommitCount() throws GitCommitIdExecutionException;
 
   void finalCleanUp() throws GitCommitIdExecutionException;
+
+  AheadBehind getAheadBehind() throws GitCommitIdExecutionException;
 
 }

src/main/java/pl/project13/maven/git/JGitProvider.java

@@ -19,8 +19,11 @@
 
 import com.google.common.annotations.VisibleForTesting;
 
+import org.eclipse.jgit.api.FetchCommand;
+import org.eclipse.jgit.api.Git;
 import org.eclipse.jgit.api.errors.GitAPIException;
 import org.eclipse.jgit.lib.AbbreviatedObjectId;
+import org.eclipse.jgit.lib.BranchTrackingStatus;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.lib.Ref;
@@ -286,6 +289,27 @@ private Repository getGitRepository() throws GitCommitIdExecutionException {
 
     return repository;
   }
+
+  @Override
+  public AheadBehind getAheadBehind() throws GitCommitIdExecutionException {
+    try {
+      fetch();
+      Optional<BranchTrackingStatus> branchTrackingStatus = Optional.ofNullable(BranchTrackingStatus.of(git, getBranchName()));
+      return branchTrackingStatus.map(bts -> AheadBehind.of(bts.getAheadCount(), bts.getBehindCount()))
+                                 .orElse(AheadBehind.NO_REMOTE);
+    } catch (Exception e) {
+      throw new GitCommitIdExecutionException("Failed to read ahead behind count: " + e.getMessage(), e);
+    }
+  }
+
+  private void fetch() {
+    FetchCommand fetchCommand = Git.wrap(git).fetch();
+    try {
+      fetchCommand.setThin(true).call();
+    } catch (Exception e) {
+      log.error("Failed to perform fetch", e);
+    }
+  }
 
   // SETTERS FOR TESTS ----------------------------------------------------
 

src/main/java/pl/project13/maven/git/NativeGitProvider.java

@@ -25,6 +25,7 @@
 import java.io.*;
 import java.nio.charset.StandardCharsets;
 import java.text.SimpleDateFormat;
+import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 
 
@@ -465,5 +466,39 @@ public boolean runEmpty(File directory, long nativeGitTimeoutInMs, String comman
       return empty; // was non-empty
     }
   }
+
+  @Override
+  public AheadBehind getAheadBehind() throws GitCommitIdExecutionException {
+    try {
+      Optional<String> remoteBranch = remoteBranch();
+      if (!remoteBranch.isPresent()) {
+        return AheadBehind.NO_REMOTE;
+      }
+      fetch(remoteBranch.get());
+      String ahead = runQuietGitCommand(canonical, nativeGitTimeoutInMs, "rev-list --right-only --count " + remoteBranch.get() + "..." + getBranchName());
+      String behind = runQuietGitCommand(canonical, nativeGitTimeoutInMs, "rev-list --left-only --count " + remoteBranch.get() + "..." + getBranchName());
+      return AheadBehind.of(ahead, behind);
+    } catch (Exception e) {
+      throw new GitCommitIdExecutionException("Failed to read ahead behind count: " + e.getMessage(), e);
+    }
+  }
+
+  private Optional<String> remoteBranch() {
+    try {
+      String remoteRef = runQuietGitCommand(canonical, nativeGitTimeoutInMs, "symbolic-ref -q HEAD");
+      String remoteBranch = runQuietGitCommand(canonical, nativeGitTimeoutInMs, "for-each-ref --format=%(upstream:short) " + remoteRef);
+      return Optional.ofNullable(remoteBranch.isEmpty() ? null : remoteBranch);
+    } catch (Exception e) {
+      return Optional.empty();
+    }
+  }
+
+  private void fetch(String remoteBranch) {
+    try {
+      runQuietGitCommand(canonical, nativeGitTimeoutInMs, "fetch " + remoteBranch.replaceFirst("/", " "));
+    } catch (Exception e) {
+      log.error("Failed to execute fetch", e);
+    }
+  }
 }
 

src/test/java/pl/project13/maven/git/NativeAndJGitProviderTest.java

@@ -44,7 +44,9 @@ public class NativeAndJGitProviderTest extends GitIntegrationTest {
     "git.commit.message.short",
     "git.commit.time",
     "git.total.commit.count",
-    "git.remote.origin.url"
+    "git.remote.origin.url",
+    "git.branch.ahead",
+    "git.branch.behind"
   };
 
   public static final String DEFAULT_FORMAT_STRING  = "yyyy-MM-dd'T'HH:mm:ssZ";
@@ -87,7 +89,7 @@ public void testCompareSubrepoInChild() throws Exception {
   }
 
   @Test
-  public void testCompareISO8601Time() throws Exception {
+  public void testCompareIso8601Time() throws Exception {
     // Test on all available basic repos to ensure that the output is identical.
     for (AvailableGitTestRepo testRepo : AvailableGitTestRepo.values()) {
       if (testRepo != AvailableGitTestRepo.GIT_COMMIT_ID) {