Merge pull request #694 from johannespfeiffer/master

[JENKINS-60564] Rebase before push

Author: MarkEWaite

src/main/java/hudson/plugins/git/GitPublisher.java

@@ -25,10 +25,7 @@
 import org.eclipse.jgit.transport.URIish;
 import org.jenkinsci.plugins.gitclient.GitClient;
 import org.jenkinsci.plugins.gitclient.PushCommand;
-import org.kohsuke.stapler.AncestorInPath;
-import org.kohsuke.stapler.DataBoundConstructor;
-import org.kohsuke.stapler.QueryParameter;
-import org.kohsuke.stapler.StaplerRequest;
+import org.kohsuke.stapler.*;
 
 import javax.servlet.ServletException;
 import java.io.IOException;
@@ -295,10 +292,20 @@ else if (!tagExists) {
 
                         // expand environment variables in remote repository
                         remote = gitSCM.getParamExpandedRepo(environment, remote);
+                        remoteURI = remote.getURIs().get(0);
+
+                        if (b.getRebaseBeforePush()) {
+                            listener.getLogger().println("Fetch and rebase with " + branchName + " of " + targetRepo);
+                            git.fetch_().from(remoteURI, remote.getFetchRefSpecs()).execute();
+                            if (!git.revParse("HEAD").equals(git.revParse(targetRepo + "/" + branchName))) {
+                                git.rebase().setUpstream(targetRepo + "/" + branchName).execute();
+                            } else {
+                                listener.getLogger().println("No rebase required. HEAD equals " + targetRepo + "/" + branchName);
+                            }
+                        }
 
                         listener.getLogger().println("Pushing HEAD to branch " + branchName + " at repo "
                                                      + targetRepo);
-                        remoteURI = remote.getURIs().get(0);
                         PushCommand push = git.push().to(remoteURI).ref("HEAD:" + branchName).force(forcePush);
                         push.execute();
                     } catch (GitException e) {
@@ -478,6 +485,7 @@ public void setEmptyTargetRepoToOrigin(){
 
     public static final class BranchToPush extends PushConfig {
         private String branchName;
+        private boolean rebaseBeforePush;
 
         public String getBranchName() {
             return branchName;
@@ -489,6 +497,15 @@ public BranchToPush(String targetRepoName, String branchName) {
             this.branchName = Util.fixEmptyAndTrim(branchName);
         }
 
+        @DataBoundSetter
+        public void setRebaseBeforePush(boolean shouldRebase) {
+            this.rebaseBeforePush = shouldRebase;
+        }
+
+        public boolean getRebaseBeforePush() {
+            return rebaseBeforePush;
+        }
+
         @Extension
         public static class DescriptorImpl extends Descriptor<PushConfig> {
             @Override

src/main/resources/hudson/plugins/git/GitPublisher/config.jelly

@@ -64,6 +64,10 @@
             <f:textbox
                 checkUrl="'descriptorByName/GitPublisher/checkRemote?value='+escape(this.value)" />
           </f:entry>
+          <f:entry field="rebaseBeforePush"
+                   title="${%Rebase before push}">
+            <f:checkbox />
+          </f:entry>
         </table>
         <div align="right">
           <input type="button" value="${%Delete Branch}" class="repeatable-delete" style="margin-left: 1em;" />

src/test/java/hudson/plugins/git/GitPublisherTest.java

@@ -38,12 +38,14 @@
 import hudson.plugins.git.extensions.impl.PreBuildMerge;
 import hudson.scm.NullSCM;
 import hudson.tasks.BuildStepDescriptor;
+import hudson.tasks.Builder;
 import hudson.util.StreamTaskListener;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.jenkinsci.plugins.gitclient.MergeCommand;
 import org.jvnet.hudson.test.Issue;
 
+import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
@@ -601,6 +603,50 @@ public void testMergeAndPushWithSkipTagEnabled() throws Exception {
       assertEquals(sha1, testGitClient.revParse(Constants.HEAD).name());
     }
 
+    @Test
+    public void testRebaseBeforePush() throws Exception {
+        FreeStyleProject project = setupSimpleProject("master");
+
+        GitSCM scm = new GitSCM(
+                remoteConfigs(),
+                Collections.singletonList(new BranchSpec("master")),
+                false, Collections.<SubmoduleConfig>emptyList(),
+                null, null,
+                Collections.<GitSCMExtension>emptyList());
+        project.setScm(scm);
+
+        BranchToPush btp = new BranchToPush("origin", "master");
+        btp.setRebaseBeforePush(true);
+
+        GitPublisher rebasedPublisher = new GitPublisher(
+                Collections.<TagToPush>emptyList(),
+                Collections.singletonList(btp),
+                Collections.<NoteToPush>emptyList(),
+                true, true, true);
+        project.getPublishersList().add(rebasedPublisher);
+
+        project.getBuildersList().add(new LongRunningCommit(testGitDir));
+        project.save();
+
+        // Assume during our build someone else pushed changes (commitFile1) to the remote repo.
+        // So our own changes (commitFile2) cannot be pushed back to the remote origin.
+        //
+        // * 0eb2599 (HEAD) Added a file named commitFile2
+        // | * 64e71e7 (origin/master) Added a file named commitFile1
+        // |/
+        // * b2578eb init
+        //
+        // What we can do is to fetch the remote changes and rebase our own changes:
+        //
+        // * 0e7674c (HEAD) Added a file named commitFile2
+        // * 64e71e7 (origin/master) Added a file named commitFile1
+        // * b2578eb init
+
+
+        // as we have set "rebaseBeforePush" to true we expect all files to be present after the build.
+        FreeStyleBuild build = build(project, Result.SUCCESS, "commitFile1", "commitFile2");
+    }
+
     @Issue("JENKINS-24786")
     @Test
     public void testMergeAndPushWithCharacteristicEnvVar() throws Exception {
@@ -738,3 +784,29 @@ private boolean isWindows() {
         return java.io.File.pathSeparatorChar==';';
     }
 }
+
+class LongRunningCommit extends Builder {
+
+    private File remoteGitDir;
+
+    LongRunningCommit(File remoteGitDir) {
+        this.remoteGitDir = remoteGitDir;
+    }
+
+    @Override
+    public boolean perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) throws InterruptedException, IOException {
+
+        TestGitRepo workspaceGit = new TestGitRepo("workspace", new File(build.getWorkspace().getRemote()), listener);
+        TestGitRepo remoteGit = new TestGitRepo("remote", this.remoteGitDir, listener);
+
+        // simulate an external commit and push to the remote during the build of our project.
+        ObjectId headRev = remoteGit.git.revParse("HEAD");
+        remoteGit.commit("commitFile1", remoteGit.johnDoe, "Added a file commitFile1");
+        remoteGit.git.checkout(headRev.getName()); // allow to push to this repo later
+
+        // commit onto the initial commit (creates a head with our changes later).
+        workspaceGit.commit("commitFile2", remoteGit.johnDoe, "Added a file commitFile2");
+
+        return true;
+    }
+}