TechDocs: techdocs backend tests (#2196)

* add tests for generators class

* add tests for helpers

* renaming

* fixup

plugins/techdocs-backend/src/techdocs/stages/generate/generators.test.ts

@@ -0,0 +1,47 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { Generators, TechdocsGenerator } from './';
+import { getVoidLogger } from '@backstage/backend-common';
+
+const logger = getVoidLogger();
+
+const mockEntity = {
+  apiVersion: 'version',
+  kind: 'TestKind',
+  metadata: {
+    name: 'testName',
+  },
+};
+
+describe('generators', () => {
+  it('should return error if no generator is registered', async () => {
+    const generators = new Generators();
+
+    expect(() => generators.get(mockEntity)).toThrowError(
+      'No generator registered for entity: "techdocs"',
+    );
+  });
+
+  it('should return correct registered generator', async () => {
+    const generators = new Generators();
+    const techdocs = new TechdocsGenerator(logger);
+
+    generators.register('techdocs', techdocs);
+
+    expect(generators.get(mockEntity)).toBe(techdocs);
+  });
+});

plugins/techdocs-backend/src/techdocs/stages/generate/generators.ts

@@ -15,32 +15,29 @@
  */
 
 import {
-    GeneratorBase,
-    SupportedGeneratorKey,
-    GeneratorBuilder,
-  } from './types';
-  
-  import { Entity } from '@backstage/catalog-model';
-  import { getGeneratorKey } from './helpers';
-  
-  export class Generators implements GeneratorBuilder {
-    private generatorMap = new Map<SupportedGeneratorKey, GeneratorBase>();
-  
-    register(templaterKey: SupportedGeneratorKey, templater: GeneratorBase) {
-      this.generatorMap.set(templaterKey, templater);
-    }
-  
-    get(entity: Entity): GeneratorBase {
-      const generatorKey = getGeneratorKey(entity);
-      const generator = this.generatorMap.get(generatorKey);
-  
-      if (!generator) {
-        throw new Error(
-          `No generator registered for entity: "${generatorKey}"`,
-        );
-      }
-  
-      return generator;
-    }
+  GeneratorBase,
+  SupportedGeneratorKey,
+  GeneratorBuilder,
+} from './types';
+
+import { Entity } from '@backstage/catalog-model';
+import { getGeneratorKey } from './helpers';
+
+export class Generators implements GeneratorBuilder {
+  private generatorMap = new Map<SupportedGeneratorKey, GeneratorBase>();
+
+  register(generatorKey: SupportedGeneratorKey, generator: GeneratorBase) {
+    this.generatorMap.set(generatorKey, generator);
   }
-  
+
+  get(entity: Entity): GeneratorBase {
+    const generatorKey = getGeneratorKey(entity);
+    const generator = this.generatorMap.get(generatorKey);
+
+    if (!generator) {
+      throw new Error(`No generator registered for entity: "${generatorKey}"`);
+    }
+
+    return generator;
+  }
+}

plugins/techdocs-backend/src/techdocs/stages/generate/helpers.test.ts

@@ -0,0 +1,103 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import Stream, { PassThrough } from 'stream';
+import os from 'os';
+import Docker from 'dockerode';
+import { runDockerContainer, getGeneratorKey } from './helpers';
+
+const mockEntity = {
+  apiVersion: 'version',
+  kind: 'TestKind',
+  metadata: {
+    name: 'testName',
+  },
+};
+
+const mockDocker = new Docker() as jest.Mocked<Docker>;
+
+describe('helpers', () => {
+  describe('getGeneratorKey', () => {
+    it('should return techdocs as the only generator key', () => {
+      const key = getGeneratorKey(mockEntity);
+      expect(key).toBe('techdocs');
+    });
+  });
+
+  describe('runDockerContainer', () => {
+    beforeEach(() => {
+      jest.spyOn(mockDocker, 'pull').mockImplementation((async (
+        _image: string,
+        _something: any,
+        handler: (err: Error | undefined, stream: PassThrough) => void,
+      ) => {
+        const mockStream = new PassThrough();
+        handler(undefined, mockStream);
+        mockStream.end();
+      }) as any);
+
+      jest
+        .spyOn(mockDocker, 'run')
+        .mockResolvedValue([{ Error: null, StatusCode: 0 }]);
+    });
+
+    const imageName = 'spotify/techdocs';
+    const args = ['build', '-d', '/result'];
+    const docsDir = os.tmpdir();
+    const resultDir = os.tmpdir();
+
+    it('should pull the techdocs docker container', async () => {
+      await runDockerContainer({
+        imageName,
+        args,
+        docsDir,
+        resultDir,
+        dockerClient: mockDocker,
+      });
+
+      expect(mockDocker.pull).toHaveBeenCalledWith(
+        imageName,
+        {},
+        expect.any(Function),
+      );
+    });
+
+    it('should run the techdocs docker container', async () => {
+      await runDockerContainer({
+        imageName,
+        args,
+        docsDir,
+        resultDir,
+        dockerClient: mockDocker,
+      });
+
+      expect(mockDocker.run).toHaveBeenCalledWith(
+        imageName,
+        args,
+        expect.any(Stream),
+        {
+          Volumes: {
+            '/content': {},
+            '/result': {},
+          },
+          WorkingDir: '/content',
+          HostConfig: {
+            Binds: [`${docsDir}:/content`, `${resultDir}:/result`],
+          },
+        },
+      );
+    });
+  });
+});