GitLab MR: introduce skip commit action.

Signed-off-by: Matt Benson <gudnabrsam@gmail.com>

.changeset/few-hairs-compare.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend-module-gitlab': minor
+---
+
+GitLab MR: introduce 'skip' commit action.

plugins/scaffolder-backend-module-gitlab/package.json

@@ -55,6 +55,7 @@
     "@gitbeaker/node": "^35.8.0",
     "@gitbeaker/rest": "^39.25.0",
     "luxon": "^3.0.0",
+    "winston": "^3.2.1",
     "yaml": "^2.0.0",
     "zod": "^3.22.4"
   },

plugins/scaffolder-backend-module-gitlab/report.api.md

@@ -193,7 +193,7 @@ export const createPublishGitlabMergeRequestAction: (options: {
     sourcePath?: string | undefined;
     targetPath?: string | undefined;
     token?: string | undefined;
-    commitAction?: 'auto' | 'update' | 'delete' | 'create' | undefined;
+    commitAction?: 'auto' | 'update' | 'delete' | 'create' | 'skip' | undefined;
     projectid?: string | undefined;
     removeSourceBranch?: boolean | undefined;
     assignee?: string | undefined;

plugins/scaffolder-backend-module-gitlab/src/actions/gitlabMergeRequest.test.ts

@@ -30,6 +30,22 @@ const mockGitlabClient = {
   },
   Branches: {
     create: jest.fn(),
+    show: jest.fn(async (_repoID: string | number, name: string) => {
+      if (['main', 'existing-branch'].includes(name)) {
+        return {
+          name,
+          merged: name === 'main',
+          protected: name === 'main',
+          default: name === 'main',
+          developers_can_push: name !== 'main',
+          developers_can_merge: name !== 'main',
+          can_push: name !== 'main',
+          web_url: `https://foo.bar.baz/owner/repo/-/tree/${name}`,
+          commit: { message: 'last change' },
+        };
+      }
+      throw new Error(`Unknown branch ${name}`);
+    }),
   },
   Commits: {
     create: jest.fn(),
@@ -83,6 +99,28 @@ const mockGitlabClient = {
       },
     ),
   },
+  RepositoryFiles: {
+    show: jest.fn(
+      async (repoID: string | number, filePath: string, ref: string) => {
+        if (repoID !== 'owner/repo') throw new Error('repo does not exist');
+        if (filePath !== 'source/auto.txt')
+          throw new Error('filePath does not exist');
+        return {
+          file_name: 'auto.txt',
+          file_path: 'source/auto.txt',
+          size: 11,
+          encoding: 'base64',
+          content: 'Zm9vLWJhci1iYXo=',
+          content_sha256:
+            '269dce1a5bb90188b2d9cf542a7c30e410c7d8251e34a97bfea56062df51ae23',
+          ref,
+          blob_id: 'a1e8f8d745cc87e3a9248358d9352bb7f9a0aeba',
+          commit_id: 'd5a3ff139356ce33e37e73add446f16869741b50',
+          last_commit_id: '570e7b2abdd848b95f2f578043fc23bd6f6fd24d',
+        };
+      },
+    ),
+  },
 };
 
 jest.mock('@gitbeaker/node', () => ({
@@ -149,6 +187,7 @@ describe('createGitLabMergeRequest', () => {
         'new-mr',
         'test',
       );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -184,6 +223,7 @@ describe('createGitLabMergeRequest', () => {
         'new-mr',
         'main',
       );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -191,7 +231,6 @@ describe('createGitLabMergeRequest', () => {
         'Create my new MR',
         { description: 'This MR is really good', removeSourceBranch: false },
       );
-
       expect(ctx.output).toHaveBeenCalledWith('targetBranchName', 'main');
     });
   });
@@ -216,6 +255,12 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -244,6 +289,12 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -278,6 +329,12 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -311,6 +368,12 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -344,6 +407,12 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -376,6 +445,12 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
       expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -404,6 +479,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -425,6 +505,16 @@ describe('createGitLabMergeRequest', () => {
           },
         ]),
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'This MR is really good',
+          removeSourceBranch: false,
+        },
+      );
     });
   });
 
@@ -446,6 +536,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -467,6 +562,16 @@ describe('createGitLabMergeRequest', () => {
           },
         ]),
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'This MR is really good',
+          removeSourceBranch: false,
+        },
+      );
     });
   });
 
@@ -490,6 +595,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -504,6 +614,16 @@ describe('createGitLabMergeRequest', () => {
           },
         ],
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
     });
 
     it('commitAction is update when update is passed in options', async () => {
@@ -525,6 +645,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -539,6 +664,16 @@ describe('createGitLabMergeRequest', () => {
           },
         ],
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
     });
 
     it('commitAction is auto when auto is passed in options', async () => {
@@ -558,6 +693,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -579,6 +719,16 @@ describe('createGitLabMergeRequest', () => {
           },
         ]),
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
     });
 
     it('commitAction is auto when auto is passed in options with targetPath', async () => {
@@ -600,6 +750,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -621,6 +776,16 @@ describe('createGitLabMergeRequest', () => {
           },
         ]),
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
     });
 
     it('commitAction is delete when delete is passed in options', async () => {
@@ -642,6 +807,11 @@ describe('createGitLabMergeRequest', () => {
       const ctx = createMockActionContext({ input, workspacePath });
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -656,6 +826,119 @@ describe('createGitLabMergeRequest', () => {
           },
         ],
       );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'other MR description',
+          removeSourceBranch: false,
+        },
+      );
+    });
+    it('commitAction skip skips commit', async () => {
+      const input = {
+        repoUrl: 'gitlab.com?repo=repo&owner=owner',
+        title: 'Create my new MR',
+        branchName: 'new-mr',
+        description: 'MR description',
+        commitAction: 'skip',
+      };
+      const ctx = createMockActionContext({ input, workspacePath });
+      await instance.handler(ctx);
+
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
+    });
+    it('commitAction skip reuses existing branch', async () => {
+      const input = {
+        repoUrl: 'gitlab.com?repo=repo&owner=owner',
+        title: 'Create my new MR',
+        branchName: 'existing-branch',
+        description: 'MR description',
+        commitAction: 'skip',
+      };
+      const ctx = createMockActionContext({ input, workspacePath });
+      await instance.handler(ctx);
+
+      expect(mockGitlabClient.Branches.show).toHaveBeenCalledWith(
+        'owner/repo',
+        'existing-branch',
+      );
+      expect(mockGitlabClient.Branches.create).not.toHaveBeenCalled();
+      expect(mockGitlabClient.Commits.create).not.toHaveBeenCalled();
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'existing-branch',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
+    });
+    it('commitAction auto skips unmodified files', async () => {
+      const input = {
+        repoUrl: 'gitlab.com?repo=repo&owner=owner',
+        title: 'Create my new MR',
+        branchName: 'new-mr',
+        description: 'MR description',
+        commitAction: 'auto',
+      };
+      mockDir.setContent({
+        [workspacePath]: {
+          source: { 'foo.txt': 'Hello there!', 'auto.txt': 'foo-bar-baz' },
+        },
+      });
+
+      const ctx = createMockActionContext({ input, workspacePath });
+      await instance.handler(ctx);
+
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
+      expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'Create my new MR',
+        expect.arrayContaining([
+          {
+            action: 'create',
+            filePath: 'source/foo.txt',
+            content: 'SGVsbG8gdGhlcmUh',
+            encoding: 'base64',
+            execute_filemode: false,
+          },
+        ]),
+      );
+      expect(mockGitlabClient.MergeRequests.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+        'Create my new MR',
+        {
+          description: 'MR description',
+          removeSourceBranch: false,
+        },
+      );
     });
   });
 
@@ -681,6 +964,11 @@ describe('createGitLabMergeRequest', () => {
 
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',
@@ -719,6 +1007,11 @@ describe('createGitLabMergeRequest', () => {
 
       await instance.handler(ctx);
 
+      expect(mockGitlabClient.Branches.create).toHaveBeenCalledWith(
+        'owner/repo',
+        'new-mr',
+        'main',
+      );
       expect(mockGitlabClient.Commits.create).toHaveBeenCalledWith(
         'owner/repo',
         'new-mr',

plugins/scaffolder-backend-module-gitlab/src/actions/gitlabMergeRequest.ts

@@ -20,25 +20,57 @@ import {
   SerializedFile,
   serializeDirectoryContents,
 } from '@backstage/plugin-scaffolder-node';
-import { Types } from '@gitbeaker/core';
+import { Gitlab, Types } from '@gitbeaker/core';
 import path from 'path';
 import { ScmIntegrationRegistry } from '@backstage/integration';
 import { InputError } from '@backstage/errors';
 import { resolveSafeChildPath } from '@backstage/backend-plugin-api';
 import { createGitlabApi } from './helpers';
 import { examples } from './gitlabMergeRequest.examples';
+import { createHash } from 'crypto';
+import { Logger } from 'winston';
 
-function getFileAction(
-  fileInfo: { file: SerializedFile; targetPath: string | undefined },
+function computeSha256(file: SerializedFile): string {
+  const hash = createHash('sha256');
+  hash.update(file.content);
+  return hash.digest('hex');
+}
+
+async function getFileAction(
+  fileInfo: { file: SerializedFile; targetPath?: string },
+  target: { repoID: string; branch: string },
+  api: Gitlab,
+  ctx: { logger: Logger },
   remoteFiles: Types.RepositoryTreeSchema[],
-  defaultCommitAction: 'create' | 'delete' | 'update' | 'auto' | undefined,
-): 'create' | 'delete' | 'update' {
-  if (!defaultCommitAction || defaultCommitAction === 'auto') {
+  defaultCommitAction:
+    | 'create'
+    | 'delete'
+    | 'update'
+    | 'skip'
+    | 'auto' = 'auto',
+): Promise<'create' | 'delete' | 'update' | 'skip'> {
+  if (defaultCommitAction === 'auto') {
     const filePath = path.join(fileInfo.targetPath ?? '', fileInfo.file.path);
-    return remoteFiles &&
-      remoteFiles.some(remoteFile => remoteFile.path === filePath)
-      ? 'update'
-      : 'create';
+    if (remoteFiles) {
+      if (remoteFiles.some(remoteFile => remoteFile.path === filePath)) {
+        try {
+          const targetFile = await api.RepositoryFiles.show(
+            target.repoID,
+            filePath,
+            target.branch,
+          );
+          if (computeSha256(fileInfo.file) === targetFile.content_sha256) {
+            return 'skip';
+          }
+        } catch (error) {
+          ctx.logger.warn(
+            `Unable to retrieve detailed information for remote file ${filePath}`,
+          );
+        }
+        return 'update';
+      }
+    }
+    return 'create';
   }
   return defaultCommitAction;
 }
@@ -62,7 +94,7 @@ export const createPublishGitlabMergeRequestAction = (options: {
     sourcePath?: string;
     targetPath?: string;
     token?: string;
-    commitAction?: 'create' | 'delete' | 'update' | 'auto';
+    commitAction?: 'create' | 'delete' | 'update' | 'skip' | 'auto';
     /** @deprecated projectID passed as query parameters in the repoUrl */
     projectid?: string;
     removeSourceBranch?: boolean;
@@ -78,7 +110,9 @@ export const createPublishGitlabMergeRequestAction = (options: {
           repoUrl: {
             type: 'string',
             title: 'Repository Location',
-            description: `Accepts the format 'gitlab.com?repo=project_name&owner=group_name' where 'project_name' is the repository name and 'group_name' is a group or username`,
+            description: `\
+Accepts the format 'gitlab.com?repo=project_name&owner=group_name' where \
+'project_name' is the repository name and 'group_name' is a group or username`,
           },
           /** @deprecated projectID is passed as query parameters in the repoUrl */
           projectid: {
@@ -109,8 +143,11 @@ export const createPublishGitlabMergeRequestAction = (options: {
           sourcePath: {
             type: 'string',
             title: 'Working Subdirectory',
-            description:
-              'Subdirectory of working directory to copy changes from',
+            description: `\
+Subdirectory of working directory to copy changes from. \
+For reasons of backward compatibility, any specified 'targetPath' input will \
+be applied in place of an absent/falsy value for this input. \
+Circumvent this behavior using '.'`,
           },
           targetPath: {
             type: 'string',
@@ -126,8 +163,9 @@ export const createPublishGitlabMergeRequestAction = (options: {
             title: 'Commit action',
             type: 'string',
             enum: ['create', 'update', 'delete', 'auto'],
-            description:
-              'The action to be used for git commit. Defaults to auto. "auto" is custom action provide by backstage, (automatic assign create or update action) /!\\ Use more api calls /!\\ *',
+            description: `\
+The action to be used for git commit. Defaults to the custom 'auto' action provided by backstage,
+which uses additional API calls in order to detect whether to 'create', 'update' or 'skip' each source file.`,
           },
           removeSourceBranch: {
             title: 'Delete source branch',
@@ -224,7 +262,7 @@ export const createPublishGitlabMergeRequestAction = (options: {
       }
 
       let remoteFiles: Types.RepositoryTreeSchema[] = [];
-      if (!ctx.input.commitAction || ctx.input.commitAction === 'auto') {
+      if ((ctx.input.commitAction ?? 'auto') === 'auto') {
         try {
           remoteFiles = await api.Repositories.tree(repoID, {
             ref: targetBranch,
@@ -238,12 +276,26 @@ export const createPublishGitlabMergeRequestAction = (options: {
         }
       }
 
-      const actions: Types.CommitAction[] = fileContents.map(file => ({
-        action: getFileAction(
-          { file, targetPath },
-          remoteFiles,
-          ctx.input.commitAction,
-        ),
+      const actions: Types.CommitAction[] = (
+        (
+          await Promise.all(
+            fileContents.map(async file =>
+              getFileAction(
+                { file, targetPath },
+                { repoID, branch: targetBranch! },
+                api,
+                ctx,
+                remoteFiles,
+                ctx.input.commitAction,
+              ).then(action => ({ file, action })),
+            ),
+          )
+        ).filter(o => o.action !== 'skip') as {
+          file: SerializedFile;
+          action: Types.CommitAction['action'];
+        }[]
+      ).map(({ file, action }) => ({
+        action,
         filePath: targetPath
           ? path.posix.join(targetPath, file.path)
           : file.path,
@@ -252,22 +304,38 @@ export const createPublishGitlabMergeRequestAction = (options: {
         execute_filemode: file.executable,
       }));
 
-      try {
-        await api.Branches.create(repoID, branchName, String(targetBranch));
-      } catch (e) {
-        throw new InputError(
-          `The branch creation failed. Please check that your repo does not already contain a branch named '${branchName}'. ${e}`,
-        );
+      let createBranch: boolean;
+      if (actions.length) {
+        createBranch = true;
+      } else {
+        try {
+          await api.Branches.show(repoID, branchName);
+          createBranch = false;
+          ctx.logger.info(
+            `Using existing branch ${branchName} without modification.`,
+          );
+        } catch (e) {
+          createBranch = true;
+        }
       }
-
-      try {
-        await api.Commits.create(repoID, branchName, ctx.input.title, actions);
-      } catch (e) {
-        throw new InputError(
-          `Committing the changes to ${branchName} failed. Please check that none of the files created by the template already exists. ${e}`,
-        );
+      if (createBranch) {
+        try {
+          await api.Branches.create(repoID, branchName, String(targetBranch));
+        } catch (e) {
+          throw new InputError(
+            `The branch creation failed. Please check that your repo does not already contain a branch named '${branchName}'. ${e}`,
+          );
+        }
+      }
+      if (actions.length) {
+        try {
+          await api.Commits.create(repoID, branchName, title, actions);
+        } catch (e) {
+          throw new InputError(
+            `Committing the changes to ${branchName} failed. Please check that none of the files created by the template already exists. ${e}`,
+          );
+        }
       }
-
       try {
         const mergeRequestUrl = await api.MergeRequests.create(
           repoID,

plugins/scaffolder-backend/report.api.md

@@ -334,7 +334,7 @@ export const createPublishGitlabMergeRequestAction: (options: {
     sourcePath?: string | undefined;
     targetPath?: string | undefined;
     token?: string | undefined;
-    commitAction?: 'auto' | 'update' | 'delete' | 'create' | undefined;
+    commitAction?: 'auto' | 'update' | 'delete' | 'create' | 'skip' | undefined;
     projectid?: string | undefined;
     removeSourceBranch?: boolean | undefined;
     assignee?: string | undefined;

yarn.lock

@@ -7456,6 +7456,7 @@ __metadata:
     "@gitbeaker/node": ^35.8.0
     "@gitbeaker/rest": ^39.25.0
     luxon: ^3.0.0
+    winston: ^3.2.1
     yaml: ^2.0.0
     zod: ^3.22.4
   languageName: unknown