Add utility function getFile in BitbucketServerClient

Can be used to fetch arbitrary files given a project and a repository
which is helpful when using custom repository parsing.

Signed-off-by: Otto Nordander <otto.nordander@resurs.se>

plugins/catalog-backend-module-bitbucket-server/api-report.md

@@ -20,6 +20,12 @@ export class BitbucketServerClient {
     config: BitbucketServerIntegrationConfig;
   }): BitbucketServerClient;
   // (undocumented)
+  getFile(options: {
+    projectKey: string;
+    repo: string;
+    path: string;
+  }): Promise<Response>;
+  // (undocumented)
   getRepository(options: {
     projectKey: string;
     repo: string;

plugins/catalog-backend-module-bitbucket-server/src/lib/BitbucketServerClient.test.ts

@@ -26,6 +26,18 @@ import { BitbucketServerProject, BitbucketServerRepository } from './types';
 
 const server = setupServer();
 
+const catalogInfoFile = `
+apiVersion: backstage.io/v1alpha1
+kind: Component
+metadata:
+  name: "backstage"
+  description: "A Backstage service"
+spec:
+  type: service
+  lifecycle: experimental
+  owner: "backstage"
+`;
+
 describe('BitbucketServerClient', () => {
   const config: BitbucketServerIntegrationConfig = {
     host: 'bitbucket.mycompany.com',
@@ -138,6 +150,31 @@ describe('BitbucketServerClient', () => {
     );
   });
 
+  it('getFile', async () => {
+    server.use(
+      rest.get(
+        `https://${config.host}/projects/test-project/repos/test-repo/raw/catalog-info.yaml`,
+        (req, res, ctx) => {
+          if (
+            req.headers.get('authorization') !==
+            'Basic dGVzdC11c2VyOnRlc3QtcHc='
+          ) {
+            return res(ctx.status(400));
+          }
+
+          return res(ctx.text(catalogInfoFile));
+        },
+      ),
+    );
+
+    const response = await client.getFile({
+      projectKey: 'test-project',
+      repo: 'test-repo',
+      path: 'catalog-info.yaml',
+    });
+    expect(await response.text()).toEqual(catalogInfoFile);
+  });
+
   it('getRepository', async () => {
     server.use(
       rest.get(

plugins/catalog-backend-module-bitbucket-server/src/lib/BitbucketServerClient.ts

@@ -60,6 +60,18 @@ export class BitbucketServerClient {
     );
   }
 
+  async getFile(options: {
+    projectKey: string;
+    repo: string;
+    path: string;
+  }): Promise<Response> {
+    const base = new URL(this.config.apiBaseUrl);
+    return fetch(
+      `${base.protocol}//${base.host}/projects/${options.projectKey}/repos/${options.repo}/raw/${options.path}`,
+      getBitbucketServerRequestOptions(this.config),
+    );
+  }
+
   async getRepository(options: {
     projectKey: string;
     repo: string;