Implement approval for merge requests

src/main/java/com/dabsquared/gitlabjenkins/gitlab/api/GitLabClient.java

@@ -36,6 +36,10 @@ public interface GitLabClient {
 
     void deleteMergeRequestEmoji(MergeRequest mr, Integer awardId);
 
+    void approveMergeRequest(MergeRequest mr);
+
+    void unapproveMergeRequest(MergeRequest mr);
+
     List<MergeRequest> getMergeRequests(String projectId, State state, int page, int perPage);
 
     List<Branch> getBranches(String projectId);

src/main/java/com/dabsquared/gitlabjenkins/gitlab/api/impl/AutodetectingGitLabClient.java

@@ -204,6 +204,32 @@ Void execute(GitLabClient client) {
         );
     }
 
+    @Override
+    public void approveMergeRequest(final MergeRequest mr) {
+        execute(
+            new GitLabOperation<Void>() {
+                @Override
+                Void execute(GitLabClient client) {
+                    client.approveMergeRequest(mr);
+                    return null;
+                }
+            }
+        );
+    }
+
+    @Override
+    public void unapproveMergeRequest(final MergeRequest mr) {
+        execute(
+            new GitLabOperation<Void>() {
+                @Override
+                Void execute(GitLabClient client) {
+                    client.unapproveMergeRequest(mr);
+                    return null;
+                }
+            }
+        );
+    }
+
     @Override
     public List<MergeRequest> getMergeRequests(final String projectId, final State state, final int page, final int perPage) {
         return execute(

src/main/java/com/dabsquared/gitlabjenkins/gitlab/api/impl/GitLabApiProxy.java

@@ -36,6 +36,10 @@ interface GitLabApiProxy {
 
     void deleteMergeRequestEmoji(Integer projectId, Integer mergeRequestId, Integer awardId);
 
+    void approveMergeRequest(Integer projectId, Integer mergeRequestId);
+
+    void unapproveMergeRequest(Integer projectId, Integer mergeRequestId);
+
     List<MergeRequest> getMergeRequests(String projectId, State state, int page, int perPage);
 
     List<Branch> getBranches(String projectId);

src/main/java/com/dabsquared/gitlabjenkins/gitlab/api/impl/ResteasyGitLabClient.java

@@ -95,6 +95,16 @@ public void deleteMergeRequestEmoji(MergeRequest mr, Integer awardId) {
         api.deleteMergeRequestEmoji(mr.getProjectId(), mergeRequestIdProvider.apply(mr), awardId);
     }
 
+    @Override
+    public void approveMergeRequest(MergeRequest mr) {
+        api.approveMergeRequest(mr.getProjectId(), mergeRequestIdProvider.apply(mr));
+    }
+
+    @Override
+    public void unapproveMergeRequest(MergeRequest mr) {
+        api.unapproveMergeRequest(mr.getProjectId(), mergeRequestIdProvider.apply(mr));
+    }
+
     @Override
     public List<MergeRequest> getMergeRequests(String projectId, State state, int page, int perPage) {
         return api.getMergeRequests(projectId, state, page, perPage);

src/main/java/com/dabsquared/gitlabjenkins/gitlab/api/impl/V3GitLabApiProxy.java

@@ -46,6 +46,26 @@ MergeRequest createMergeRequest(
         @FormParam("target_branch") String targetBranch,
         @FormParam("title") String title);
 
+    /**
+     * Unsupported in API v3
+     */
+    @POST
+    @Produces(MediaType.APPLICATION_JSON)
+    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
+    @Path("/projects/{projectId}/merge_requests/{mergeRequestIid}/approve")
+    @Override
+    void approveMergeRequest(@PathParam("projectId") Integer projectId, @PathParam("mergeRequestIid") Integer mergeRequestId);
+
+    /**
+     * Unsupported in API v3
+     */
+    @POST
+    @Produces(MediaType.APPLICATION_JSON)
+    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
+    @Path("/projects/{projectId}/merge_requests/{mergeRequestIid}/unapprove")
+    @Override
+    void unapproveMergeRequest(Integer projectId, Integer mergeRequestId);
+
     @GET
     @Produces(MediaType.APPLICATION_JSON)
     @Path("/projects/{projectName}")

src/main/java/com/dabsquared/gitlabjenkins/gitlab/api/impl/V4GitLabApiProxy.java

@@ -46,6 +46,20 @@ MergeRequest createMergeRequest(
         @FormParam("target_branch") String targetBranch,
         @FormParam("title") String title);
 
+    @POST
+    @Produces(MediaType.APPLICATION_JSON)
+    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
+    @Path("/projects/{projectId}/merge_requests/{mergeRequestIid}/approve")
+    @Override
+    void approveMergeRequest(@PathParam("projectId") Integer projectId, @PathParam("mergeRequestIid") Integer mergeRequestId);
+
+    @POST
+    @Produces(MediaType.APPLICATION_JSON)
+    @Consumes(MediaType.APPLICATION_FORM_URLENCODED)
+    @Path("/projects/{projectId}/merge_requests/{mergeRequestIid}/unapprove")
+    @Override
+    void unapproveMergeRequest(@PathParam("projectId") Integer  projectId, @PathParam("mergeRequestIid") Integer mergeRequestId);
+
     @GET
     @Produces(MediaType.APPLICATION_JSON)
     @Path("/projects/{projectName}")

src/main/java/com/dabsquared/gitlabjenkins/publisher/GitLabApproveMergeRequestPublisher.java

@@ -0,0 +1,81 @@
+package com.dabsquared.gitlabjenkins.publisher;
+
+import com.dabsquared.gitlabjenkins.gitlab.api.GitLabClient;
+import com.dabsquared.gitlabjenkins.gitlab.api.model.MergeRequest;
+import hudson.Extension;
+import hudson.model.AbstractProject;
+import hudson.model.Result;
+import hudson.model.Run;
+import hudson.model.TaskListener;
+import hudson.tasks.BuildStepDescriptor;
+import hudson.tasks.Publisher;
+import org.kohsuke.stapler.DataBoundConstructor;
+
+import javax.ws.rs.NotAuthorizedException;
+import javax.ws.rs.NotFoundException;
+import javax.ws.rs.ProcessingException;
+import javax.ws.rs.WebApplicationException;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+public class GitLabApproveMergeRequestPublisher extends MergeRequestNotifier {
+    private static final Logger LOGGER = Logger.getLogger(GitLabApproveMergeRequestPublisher.class.getName());
+
+    private final boolean approveUnstableBuilds;
+
+    @DataBoundConstructor
+    public GitLabApproveMergeRequestPublisher(boolean approveUnstableBuilds) {
+        this.approveUnstableBuilds = approveUnstableBuilds;
+    }
+
+    @Extension
+    public static class DescriptorImpl extends BuildStepDescriptor<Publisher> {
+
+        @Override
+        public boolean isApplicable(Class<? extends AbstractProject> aClass) {
+            return true;
+        }
+
+        @Override
+        public String getHelpFile() {
+            return "/plugin/gitlab-plugin/help/help-approve-gitlab-mergerequest.html";
+        }
+
+        @Override
+        public String getDisplayName() {
+            return Messages.GitLabApproveMergeRequestPublisher_DisplayName();
+        }
+    }
+
+    public boolean isApproveUnstableBuilds() {
+        return approveUnstableBuilds;
+    }
+
+    @Override
+    protected void perform(Run<?, ?> build, TaskListener listener, GitLabClient client, MergeRequest mergeRequest) {
+        try {
+            Result buildResult = build.getResult();
+            if (build.getResult() == Result.SUCCESS || (buildResult == Result.UNSTABLE && isApproveUnstableBuilds())) {
+                client.approveMergeRequest(mergeRequest);
+            } else {
+                client.unapproveMergeRequest(mergeRequest);
+            }
+        } catch (NotFoundException e) {
+            String message = String.format(
+                "Failed to approve/unapprove merge request '%s' for project '%s'.\n"
+                    + "Got unexpected 404. Does your GitLab edition or GitLab.com tier really support approvals, and are you are an eligible approver for this merge request?", mergeRequest.getIid(), mergeRequest.getProjectId());
+            listener.getLogger().printf(message);
+            LOGGER.log(Level.WARNING, message, e);
+        } catch (NotAuthorizedException e) {
+            String message = String.format(
+                "Failed to approve/unapprove merge request '%s' for project '%s'.\n"
+                + "Got unexpected 401, are you using the wrong credentials?", mergeRequest.getIid(), mergeRequest.getProjectId());
+            listener.getLogger().printf(message);
+            LOGGER.log(Level.WARNING, message, e);
+        } catch (WebApplicationException | ProcessingException e) {
+            listener.getLogger().printf("Failed to approve/unapprove merge request for project '%s': %s%n", mergeRequest.getProjectId(), e.getMessage());
+            LOGGER.log(Level.SEVERE, String.format("Failed to approve/unapprove merge request for project '%s'", mergeRequest.getProjectId()), e);
+        }
+    }
+
+}

src/main/resources/com/dabsquared/gitlabjenkins/publisher/GitLabApproveMergeRequestPublisher/config.jelly

@@ -0,0 +1,8 @@
+<?jelly escape-by-default='true'?>
+<j:jelly xmlns:j="jelly:core" xmlns:f="/lib/form">
+  <f:advanced>
+    <f:entry title="${%Approve unstable builds}" field="approveUnstableBuilds">
+      <f:checkbox default="false"/>
+    </f:entry>
+  </f:advanced>
+</j:jelly>

src/main/resources/com/dabsquared/gitlabjenkins/publisher/Messages.properties

@@ -3,3 +3,4 @@ name.required=Build name required.
 GitLabMessagePublisher.DisplayName=Add note with build status on GitLab merge requests
 GitLabVotePublisher.DisplayName=Add vote for build status on GitLab merge requests
 GitLabAcceptMergeRequestPublisher.DisplayName=Accept GitLab merge request on success
+GitLabApproveMergeRequestPublisher.DisplayName=Approve / Revoke approval on GitLab merge request (EE-only)

src/main/webapp/help/help-approve-gitlab-mergerequest.html

@@ -0,0 +1,8 @@
+<div>
+  Approve the GitLab merge request if builds succeeds, or revoke the approval if it fails.<br/>
+  The approval will be visible merge request UI. You must have at least one GitLab connection/server configured in the Jenkins global configuration.
+  <p>
+    <b><span style="background-color:#ff5c33;">Feature availability warning:</span></b>
+    Merge request approvals are not available in every <a href="https://docs.gitlab.com/ee/user/project/merge_requests/merge_request_approvals.html" target="_blank">GitLab Edition or GitLab.com tier</a>.
+  </p>
+</div>

src/test/java/com/dabsquared/gitlabjenkins/publisher/GitLabApproveMergeRequestPublisherTest.java

@@ -0,0 +1,123 @@
+package com.dabsquared.gitlabjenkins.publisher;
+
+import hudson.model.AbstractBuild;
+import hudson.model.BuildListener;
+import hudson.model.Result;
+import hudson.model.StreamBuildListener;
+import org.junit.*;
+import org.jvnet.hudson.test.JenkinsRule;
+import org.mockserver.client.server.MockServerClient;
+import org.mockserver.junit.MockServerRule;
+import org.mockserver.model.HttpRequest;
+
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.nio.charset.Charset;
+
+import static com.dabsquared.gitlabjenkins.publisher.TestUtility.*;
+import static org.mockserver.model.HttpRequest.request;
+import static org.mockserver.model.HttpResponse.response;
+
+public class GitLabApproveMergeRequestPublisherTest {
+
+    @ClassRule
+    public static MockServerRule mockServer = new MockServerRule(new Object());
+
+    @ClassRule
+    public static JenkinsRule jenkins = new JenkinsRule();
+
+    private MockServerClient mockServerClient;
+    private BuildListener listener;
+
+    @BeforeClass
+    public static void setupClass() throws IOException {
+        setupGitLabConnections(jenkins, mockServer);
+    }
+
+    @Before
+    public void setup() {
+        listener = new StreamBuildListener(jenkins.createTaskListener().getLogger(), Charset.defaultCharset());
+        mockServerClient = new MockServerClient("localhost", mockServer.getPort());
+    }
+
+    @After
+    public void cleanup() {
+        mockServerClient.reset();
+    }
+
+    @Test
+    public void matrixAggregatable() throws InterruptedException, IOException {
+        verifyMatrixAggregatable(GitLabApproveMergeRequestPublisher.class, listener);
+    }
+
+    @Test
+    public void success_approve_unstable_v4() throws IOException, InterruptedException {
+        performApprovalAndVerify(mockSimpleBuild(GITLAB_CONNECTION_V4, Result.SUCCESS), "v4", MERGE_REQUEST_IID, true);
+    }
+
+    @Test
+    public void success_v4() throws IOException, InterruptedException {
+        performApprovalAndVerify(mockSimpleBuild(GITLAB_CONNECTION_V4, Result.SUCCESS), "v4", MERGE_REQUEST_IID, false);
+    }
+
+    @Test
+    public void unstable_approve_unstable_v4() throws IOException, InterruptedException {
+        performApprovalAndVerify(mockSimpleBuild(GITLAB_CONNECTION_V4, Result.UNSTABLE), "v4", MERGE_REQUEST_IID, true);
+    }
+
+    @Test
+    public void unstable_dontapprove_v4() throws IOException, InterruptedException {
+        performUnapprovalAndVerify(mockSimpleBuild(GITLAB_CONNECTION_V4, Result.UNSTABLE), "v4", MERGE_REQUEST_IID, false);
+    }
+
+    @Test
+    public void failed_approve_unstable_v4() throws IOException, InterruptedException {
+        performUnapprovalAndVerify(mockSimpleBuild(GITLAB_CONNECTION_V4, Result.FAILURE), "v4", MERGE_REQUEST_IID, true);
+    }
+
+    @Test
+    public void failed_v4() throws IOException, InterruptedException {
+        performUnapprovalAndVerify(mockSimpleBuild(GITLAB_CONNECTION_V4, Result.FAILURE), "v4", MERGE_REQUEST_IID, false);
+    }
+
+    private void performApprovalAndVerify(AbstractBuild build, String apiLevel, int mergeRequestId, boolean approveUnstable) throws InterruptedException, IOException {
+        GitLabApproveMergeRequestPublisher publisher = preparePublisher(new GitLabApproveMergeRequestPublisher(approveUnstable), build);
+        publisher.perform(build, null, listener);
+
+        mockServerClient.verify(prepareSendApprovalWithSuccessResponse(build, apiLevel, mergeRequestId));
+    }
+
+    private void performUnapprovalAndVerify(AbstractBuild build, String apiLevel, int mergeRequestId, boolean approveUnstable) throws InterruptedException, IOException {
+        GitLabApproveMergeRequestPublisher publisher = preparePublisher(new GitLabApproveMergeRequestPublisher(approveUnstable), build);
+        publisher.perform(build, null, listener);
+
+        mockServerClient.verify(prepareSendUnapprovalWithSuccessResponse(build, apiLevel, mergeRequestId));
+    }
+
+    private HttpRequest prepareSendApprovalWithSuccessResponse(AbstractBuild build, String apiLevel, int mergeRequestId) throws UnsupportedEncodingException {
+        HttpRequest approvalRequest = prepareSendApproval(apiLevel, mergeRequestId);
+        mockServerClient.when(approvalRequest).respond(response().withStatusCode(200));
+        return approvalRequest;
+    }
+
+    private HttpRequest prepareSendUnapprovalWithSuccessResponse(AbstractBuild build, String apiLevel, int mergeRequestId) throws UnsupportedEncodingException {
+        HttpRequest unapprovalRequest = prepareSendUnapproval(apiLevel, mergeRequestId);
+        mockServerClient.when(unapprovalRequest).respond(response().withStatusCode(200));
+        return unapprovalRequest;
+    }
+
+    private HttpRequest prepareSendApproval(final String apiLevel, int mergeRequestId) throws UnsupportedEncodingException {
+        return request()
+            .withPath("/gitlab/api/" + apiLevel + "/projects/" + PROJECT_ID + "/merge_requests/" + mergeRequestId + "/approve")
+            .withMethod("POST")
+            .withHeader("PRIVATE-TOKEN", "secret");
+    }
+
+    private HttpRequest prepareSendUnapproval(final String apiLevel, int mergeRequestId) throws UnsupportedEncodingException {
+        return request()
+            .withPath("/gitlab/api/" + apiLevel + "/projects/" + PROJECT_ID + "/merge_requests/" + mergeRequestId + "/unapprove")
+            .withMethod("POST")
+            .withHeader("PRIVATE-TOKEN", "secret");
+    }
+
+}

src/test/java/com/dabsquared/gitlabjenkins/service/GitLabClientStub.java

@@ -142,6 +142,16 @@ public List<Awardable> getMergeRequestEmoji(MergeRequest mr) {
     @Override
     public void deleteMergeRequestEmoji(MergeRequest mr, Integer awardId) {
 
+    }
+
+    @Override
+    public void approveMergeRequest(MergeRequest mr) {
+
+    }
+
+    @Override
+    public void unapproveMergeRequest(MergeRequest mr) {
+
     }
 
     @Override

src/test/java/com/dabsquared/gitlabjenkins/util/GitLabClientStub.java

@@ -88,6 +88,16 @@ public void deleteMergeRequestEmoji(MergeRequest mr, Integer awardId) {
 
     }
 
+    @Override
+    public void approveMergeRequest(MergeRequest mr) {
+
+    }
+
+    @Override
+    public void unapproveMergeRequest(MergeRequest mr) {
+
+    }
+
     @Override
     public List<MergeRequest> getMergeRequests(String projectId, State state, int page, int perPage) {
         return null;