Merge branch 'master' of github.com:spotify/backstage into blam/scaffolder

* 'master' of github.com:spotify/backstage:
  [Plugin] Explore features in Backstage (#696)
  [Storybook] Fix Storybook compilation warnings (#701)
  Make the inventory backend standalone runnable

.github/CODEOWNERS

@@ -4,4 +4,4 @@
 # The last matching pattern takes precedence.
 # https://help.github.com/articles/about-codeowners/
 
-* @spotify/backstage-core
+*                @spotify/backstage-core

package.json

@@ -32,7 +32,7 @@
     "husky": "^4.2.3",
     "lerna": "^3.20.2",
     "lint-staged": "^10.1.0",
-    "prettier": "^1.19.1"
+    "prettier": "^2.0.5"
   },
   "husky": {
     "hooks": {

packages/app/package.json

@@ -20,6 +20,7 @@
   "dependencies": {
     "@backstage/cli": "^0.1.1-alpha.4",
     "@backstage/core": "^0.1.1-alpha.4",
+    "@backstage/plugin-explore": "^0.1.1-alpha.4",
     "@backstage/plugin-home-page": "^0.1.1-alpha.4",
     "@backstage/plugin-inventory": "^0.1.1-alpha.4",
     "@backstage/plugin-lighthouse": "^0.1.1-alpha.4",

packages/app/src/components/Root/Root.tsx

@@ -18,6 +18,7 @@ import React, { FC, useContext } from 'react';
 import PropTypes from 'prop-types';
 import { Link, makeStyles, Typography } from '@material-ui/core';
 import HomeIcon from '@material-ui/icons/Home';
+import ExploreIcon from '@material-ui/icons/Explore';
 import AccountCircle from '@material-ui/icons/AccountCircle';
 import CreateComponentIcon from '@material-ui/icons/Create';
 import AccountTreeIcon from '@material-ui/icons/AccountTree';
@@ -81,7 +82,9 @@ const Root: FC<{}> = ({ children }) => (
       <SidebarSpacer />
       <SidebarDivider />
       <SidebarItem icon={HomeIcon} to="/" text="Home" />
+      <SidebarItem icon={ExploreIcon} to="/explore" text="Explore" />
       <SidebarItem icon={CreateComponentIcon} to="/scaffolder" text="Create" />
+      <SidebarDivider />      
       <SidebarItem icon={AccountTreeIcon} to="/inventory" text="Inventory" />
       <SidebarItem icon={AccountCircle} to="/login" text="Login" />
       <SidebarDivider />

packages/app/src/plugins.ts

@@ -13,10 +13,10 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 export { plugin as HomePagePlugin } from '@backstage/plugin-home-page';
 export { plugin as WelcomePlugin } from '@backstage/plugin-welcome';
 export { plugin as LighthousePlugin } from '@backstage/plugin-lighthouse';
 export { plugin as InventoryPlugin } from '@backstage/plugin-inventory';
 export { plugin as ScaffolderPlugin } from '@backstage/plugin-scaffolder';
 export { plugin as TechRadar } from '@backstage/plugin-tech-radar';
+export { plugin as Explore } from '@backstage/plugin-explore';

packages/backend-common/README.md

@@ -24,8 +24,8 @@ import {
 const app = express();
 app.use(requestLoggingHandler());
 app.use('/home', myHomeRouter);
-app.use(errorHandler());
 app.use(notFoundHandler());
+app.use(errorHandler());
 
 app.listen(PORT, () => {
   getRootLogger().info(`Listening on port ${PORT}`);

packages/backend/src/index.ts

@@ -28,32 +28,38 @@ import {
   notFoundHandler,
   requestLoggingHandler,
 } from '@backstage/backend-common';
-import { router as inventoryRouter } from '@backstage/plugin-inventory-backend';
+import { createRouter as inventoryRouter } from '@backstage/plugin-inventory-backend';
+import { createScaffolder } from '@backstage/plugin-scaffolder-backend';
 import compression from 'compression';
 import cors from 'cors';
 import express from 'express';
 import helmet from 'helmet';
 import { testRouter } from './test';
-import { createScaffolder } from '@backstage/plugin-scaffolder-backend';
 
 const DEFAULT_PORT = 7000;
-
 const PORT = parseInt(process.env.PORT ?? '', 10) || DEFAULT_PORT;
-const app = express();
+const logger = getRootLogger().child({ type: 'plugin' });
 
-const scaffolder = createScaffolder();
+async function main() {
+  const inventory = await inventoryRouter({ logger });
+  const scaffolder = createScaffolder();
 
-app.use(helmet());
-app.use(cors());
-app.use(compression());
-app.use(express.json());
-app.use(requestLoggingHandler());
-app.use('/test', testRouter);
-app.use('/inventory', inventoryRouter);
-app.use('/scaffolder', scaffolder);
-app.use(errorHandler());
-app.use(notFoundHandler());
+  const app = express();
 
-app.listen(PORT, () => {
-  getRootLogger().info(`Listening on port ${PORT}`);
-});
+  app.use(helmet());
+  app.use(cors());
+  app.use(compression());
+  app.use(express.json());
+  app.use(requestLoggingHandler());
+  app.use('/test', testRouter);
+  app.use('/inventory', inventory);
+  app.use('/scaffolder', scaffolder);
+  app.use(notFoundHandler());
+  app.use(errorHandler());
+
+  app.listen(PORT, () => {
+    getRootLogger().info(`Listening on port ${PORT}`);
+  });
+}
+
+main();

packages/core/src/components/Sequence/index.ts

@@ -14,4 +14,5 @@
  * limitations under the License.
  */
 
-export { default, StepType } from './Sequence';
+export { default } from './Sequence';
+export type { StepType } from './Sequence';

packages/core/src/index.ts

@@ -16,7 +16,8 @@
 
 export * from './api';
 export { default as Page } from './layout/Page';
-export { gradients, pageTheme, PageTheme } from './layout/Page';
+export { gradients, pageTheme } from './layout/Page';
+export type { PageTheme } from './layout/Page';
 export { default as Content } from './layout/Content/Content';
 export { default as ContentHeader } from './layout/ContentHeader/ContentHeader';
 export { default as Header } from './layout/Header/Header';

packages/core/src/layout/BottomLink/index.ts

@@ -14,4 +14,5 @@
  * limitations under the License.
  */
 
-export { default, Props } from './BottomLink';
+export { default } from './BottomLink';
+export type { Props } from './BottomLink';

packages/core/src/layout/Page/index.ts

@@ -15,4 +15,5 @@
  */
 
 export { default } from './Page';
-export { gradients, pageTheme, PageTheme } from './PageThemeProvider';
+export { gradients, pageTheme } from './PageThemeProvider';
+export type { PageTheme } from './PageThemeProvider';

plugins/explore/.eslintrc.js

@@ -0,0 +1,3 @@
+module.exports = {
+  extends: [require.resolve('@backstage/cli/config/eslint')],
+};

plugins/explore/README.md

@@ -0,0 +1,6 @@
+# Title
+Welcome to the explore plugin!
+
+## Sub-section 1
+
+## Sub-section 2

plugins/explore/package.json

@@ -0,0 +1,39 @@
+{
+  "name": "@backstage/plugin-explore",
+  "version": "0.1.1-alpha.4",
+  "main": "dist/index.esm.js",
+  "types": "dist/index.d.ts",
+  "license": "Apache-2.0",
+  "private": true,
+  "scripts": {
+    "build": "backstage-cli plugin:build",
+    "lint": "backstage-cli lint",
+    "test": "backstage-cli test",
+    "clean": "backstage-cli clean"
+  },
+  "devDependencies": {
+    "@backstage/cli": "^0.1.1-alpha.4",
+    "@backstage/test-utils": "^0.1.1-alpha.4",
+    "@testing-library/jest-dom": "^4.2.4",
+    "@testing-library/react": "^9.3.2",
+    "@testing-library/user-event": "^7.1.2",
+    "@types/jest": "^24.0.0",
+    "@types/node": "^12.0.0",
+    "@types/testing-library__jest-dom": "5.0.2",
+    "jest-fetch-mock": "^3.0.3"
+  },
+  "dependencies": {
+    "@backstage/core": "^0.1.1-alpha.4",
+    "@backstage/theme": "^0.1.1-alpha.4",
+    "@material-ui/core": "^4.9.1",
+    "@material-ui/icons": "^4.9.1",
+    "@material-ui/lab": "4.0.0-alpha.45",
+    "classnames": "^2.2.6",
+    "react": "16.13.1",
+    "react-dom": "16.13.1",
+    "react-use": "^13.0.0"
+  },
+  "files": [
+    "dist"
+  ]
+}

plugins/explore/src/components/ExploreCard.test.js

@@ -0,0 +1,93 @@
+/*
+ * 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 React from 'react';
+import { render } from '@testing-library/react';
+import { wrapInThemedTestApp } from '@backstage/test-utils';
+
+import ExploreCard from './ExploreCard';
+
+const minProps = {
+  card: {
+    title: 'Title',
+    description: 'Something something',
+    url: 'http://spotify.com/',
+    image: 'https://developer.spotify.com/assets/WebAPI_intro.png',
+    tags: ['tag1', 'tag2'],
+  },
+};
+
+describe('<ExploreCard />', () => {
+  it('renders without exploding', () => {
+    const { getByText } = render(
+      wrapInThemedTestApp(<ExploreCard {...minProps} />),
+    );
+    expect(getByText('Explore')).toBeInTheDocument();
+  });
+
+  it('renders props correctly', () => {
+    const { getByText } = render(
+      wrapInThemedTestApp(<ExploreCard {...minProps} />),
+    );
+    expect(getByText(minProps.card.title)).toBeInTheDocument();
+    expect(getByText(minProps.card.description)).toBeInTheDocument();
+  });
+
+  it('should link out', () => {
+    const rendered = render(wrapInThemedTestApp(<ExploreCard {...minProps} />));
+    const anchor = rendered.container.querySelector('a');
+    expect(anchor.href).toBe(minProps.card.url);
+  });
+
+  it('renders default description when missing', () => {
+    const propsWithoutDescription = {
+      card: {
+        card: {
+          title: 'Title',
+          url: 'http://spotify.com/',
+          image: 'https://developer.spotify.com/assets/WebAPI_intro.png',
+        },
+      },
+    };
+    const { getByText } = render(
+      wrapInThemedTestApp(<ExploreCard {...propsWithoutDescription} />),
+    );
+    expect(getByText('Description missing')).toBeInTheDocument();
+  });
+
+  it('renders lifecycle correctly', () => {
+    const propsWithLifecycle = {
+      card: {
+        title: 'Title',
+        url: 'http://spotify.com/',
+        image: 'https://developer.spotify.com/assets/WebAPI_intro.png',
+        lifecycle: 'GA',
+      },
+    };
+    const { queryByText } = render(
+      wrapInThemedTestApp(<ExploreCard {...propsWithLifecycle} />),
+    );
+    expect(queryByText('GA')).not.toBeInTheDocument();
+  });
+
+  it('renders tags correctly', () => {
+    const { getByText } = render(
+      wrapInThemedTestApp(<ExploreCard {...minProps} />),
+    );
+    expect(getByText(minProps.card.tags[0])).toBeInTheDocument();
+    expect(getByText(minProps.card.tags[1])).toBeInTheDocument();
+  });
+});

plugins/explore/src/components/ExploreCard.tsx

@@ -0,0 +1,134 @@
+/*
+ * 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 React, { FC } from 'react';
+import classNames from 'classnames';
+import {
+  Button,
+  Card,
+  CardActions,
+  CardContent,
+  CardMedia,
+  Chip,
+  Typography,
+  makeStyles,
+} from '@material-ui/core';
+import { BackstageTheme } from '@backstage/theme';
+
+const useStyles = makeStyles<BackstageTheme>(theme => ({
+  card: {
+    display: 'flex',
+    flexDirection: 'column',
+  },
+  cardActions: {
+    flexGrow: 1,
+    alignItems: 'flex-end',
+  },
+  media: {
+    height: 128,
+  },
+  mediaContain: {
+    backgroundSize: 'contain',
+  },
+  lifecycle: {
+    lineHeight: '0.8em',
+    color: 'white',
+  },
+  ga: {
+    backgroundColor: theme.palette.status.ok,
+  },
+  alpha: {
+    backgroundColor: theme.palette.status.error,
+  },
+  beta: {
+    backgroundColor: theme.palette.status.warning,
+  },
+  domains: {
+    position: 'relative',
+    top: theme.spacing(2),
+  },
+  spaceBetween: {
+    justifyContent: 'space-between',
+  },
+}));
+
+export type CardData = {
+  title: string;
+  description: string;
+  url: string;
+  image: string;
+  tags?: string[];
+  lifecycle?: string;
+  newsTag?: string;
+};
+
+type Props = {
+  card: CardData;
+  objectFit?: 'cover' | 'contain';
+};
+
+const ExploreCard: FC<Props> = ({ card, objectFit }) => {
+  const classes = useStyles();
+
+  const { title, description, url, image, lifecycle, newsTag, tags } = card;
+
+  return (
+    <Card key={title} className={classes.card}>
+      <CardMedia
+        image={image}
+        title={title}
+        className={classNames(classes.media, {
+          [classes.mediaContain]: objectFit === 'contain',
+        })}
+      />
+      <CardContent>
+        <Typography gutterBottom variant="h5">
+          {title}{' '}
+          {lifecycle && lifecycle.toLowerCase() !== 'ga' && (
+            <Chip
+              label={lifecycle}
+              className={classNames(
+                classes.lifecycle,
+                classes[lifecycle.toLowerCase()],
+              )}
+            />
+          )}
+        </Typography>
+        <Typography paragraph>
+          {description || 'Description missing'}
+        </Typography>
+        {tags && (
+          <div className={classes.domains}>
+            {tags.map((item, idx) => (
+              <Chip key={idx} label={item} />
+            ))}
+          </div>
+        )}
+      </CardContent>
+      <CardActions
+        className={classNames(classes.cardActions, {
+          [classes.spaceBetween]: newsTag,
+        })}
+      >
+        <Button size="small" color="primary" href={url} disabled={!url}>
+          Explore
+        </Button>
+      </CardActions>
+    </Card>
+  );
+};
+
+export default ExploreCard;

plugins/explore/src/components/ExplorePluginPage.tsx

@@ -0,0 +1,93 @@
+/*
+ * 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 React, { FC } from 'react';
+import { makeStyles, Typography } from '@material-ui/core';
+import {
+  Content,
+  ContentHeader,
+  Header,
+  Page,
+  pageTheme,
+  SupportButton,
+} from '@backstage/core';
+import ExploreCard, { CardData } from './ExploreCard';
+import { BackstageTheme } from '@backstage/theme';
+
+const useStyles = makeStyles<BackstageTheme>(theme => ({
+  container: {
+    display: 'grid',
+    gridTemplateColumns: 'repeat(auto-fill, 296px)',
+    gridGap: theme.spacing(3),
+    marginBottom: theme.spacing(6),
+  },
+}));
+
+const toolsCards = [
+  {
+    title: 'Lighthouse',
+    description:
+      "Google's Lighthouse tool is a great resource for benchmarking and improving the accessibility, performance, SEO, and best practices of your website.",
+    url: '/lighthouse',
+    image:
+      'https://raw.githubusercontent.com/GoogleChrome/lighthouse/8b3d7f052b2e64dd857e741d7395647f487697e7/assets/lighthouse-logo.png',
+    tags: ['web', 'seo', 'accessibility', 'performance'],
+  },
+  {
+    title: 'Tech Radar',
+    description:
+      'Tech Radar is a list of technologies, complemented by an assessment result, called ring assignment.',
+    url: '/tech-radar',
+    image:
+      'https://storage.googleapis.com/wf-blogs-engineering-media/2018/09/fe13bb32-wf-tech-radar-hero-1024x597.png',
+    tags: ['standards', 'landscape'],
+  },
+  {
+    title: 'GraphiQL',
+    description:
+      'Integrates GraphiQL as a tool to browse GraphiQL endpoints inside Backstage.',
+    url: 'graphiql',
+    image:
+      'https://camo.githubusercontent.com/517398c3fbe0687d3d4dcbe05da82970b882e75a/68747470733a2f2f64337676366c703535716a6171632e636c6f756466726f6e742e6e65742f6974656d732f33413061324e314c3346324f304c3377326e316a2f477261706869514c382e706e673f582d436c6f75644170702d56697369746f722d49643d3433363432',
+    tags: ['graphql', 'dev'],
+  },
+];
+
+const ExplorePluginPage: FC<{}> = () => {
+  const classes = useStyles();
+  return (
+    <Page theme={pageTheme.home}>
+      <Header
+        title="Explore"
+        subtitle="Tools and services available in Backstage"
+      />
+      <Content>
+        <ContentHeader title="Tools">
+          <SupportButton>
+            <Typography>Explore tools available in Backstage</Typography>
+          </SupportButton>
+        </ContentHeader>
+        <div className={classes.container}>
+          {toolsCards.map((card: CardData, ix: any) => (
+            <ExploreCard card={card} key={ix} />
+          ))}
+        </div>
+      </Content>
+    </Page>
+  );
+};
+
+export default ExplorePluginPage;

plugins/explore/src/index.ts

@@ -0,0 +1,17 @@
+/*
+ * 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.
+ */
+
+export { plugin } from './plugin';

plugins/explore/src/plugin.test.ts

@@ -0,0 +1,23 @@
+/*
+ * 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 { plugin } from './plugin';
+
+describe('explore', () => {
+  it('should export plugin', () => {
+    expect(plugin).toBeDefined();
+  });
+});

plugins/explore/src/plugin.ts

@@ -14,17 +14,12 @@
  * limitations under the License.
  */
 
-import express from 'express';
+import { createPlugin } from '@backstage/core';
+import ExplorePluginPage from './components/ExplorePluginPage';
 
-export const router = express.Router();
-
-router.get('/', async (_, res) => {
-  res
-    .status(200)
-    .send([
-      { id: 'component1' },
-      { id: 'component2' },
-      { id: 'component3' },
-      { id: 'component4' },
-    ]);
+export const plugin = createPlugin({
+  id: 'explore',
+  register({ router }) {
+    router.registerRoute('/explore', ExplorePluginPage);
+  },
 });

plugins/explore/src/setupTests.ts

@@ -0,0 +1,18 @@
+/*
+ * 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 '@testing-library/jest-dom/extend-expect';
+require('jest-fetch-mock').enableMocks();

plugins/explore/tsconfig.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.json",
+  "include": ["src"],
+  "compilerOptions": {
+    "baseUrl": "src"
+  }
+}

plugins/inventory-backend/package.json

@@ -5,18 +5,30 @@
   "license": "Apache-2.0",
   "private": true,
   "scripts": {
+    "start": "tsc-watch --onFirstSuccess \"nodemon dist/run.js\"",
     "build": "tsc",
     "lint": "backstage-cli lint",
     "test": "backstage-cli test",
     "clean": "backstage-cli clean"
   },
   "devDependencies": {
-    "@backstage/cli": "^0.1.1-alpha.4"
+    "@backstage/cli": "^0.1.1-alpha.4",
+    "jest-fetch-mock": "^3.0.3",
+    "tsc-watch": "^4.2.3"
   },
   "dependencies": {
-    "express": "^4.17.1"
+    "@backstage/backend-common": "0.1.1-alpha.4",
+    "compression": "^1.7.4",
+    "cors": "^2.8.5",
+    "express": "^4.17.1",
+    "helmet": "^3.22.0",
+    "morgan": "^1.10.0",
+    "winston": "^3.2.1"
   },
   "files": [
     "dist"
-  ]
+  ],
+  "nodemonConfig": {
+    "watch": "./dist"
+  }
 }

plugins/inventory-backend/src/index.ts

@@ -14,4 +14,4 @@
  * limitations under the License.
  */
 
-export { router } from './plugin';
+export * from './service/router';

plugins/inventory-backend/src/inventory/AggregatorInventory.ts

@@ -0,0 +1,35 @@
+/*
+ * 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 { Component, Inventory } from './types';
+
+export class AggregatorInventory implements Inventory {
+  inventories: Inventory[] = [];
+
+  list(): Promise<Array<Component>> {
+    return Promise.all(this.inventories.map(i => i.list())).then(lists =>
+      lists.flat(),
+    );
+  }
+
+  item(id: string): Promise<Component | undefined> {
+    return this.list().then(items => items.find(i => i.id === id));
+  }
+
+  enlist(inventory: Inventory) {
+    this.inventories.push(inventory);
+  }
+}

plugins/inventory-backend/src/inventory/StaticInventory.ts

@@ -0,0 +1,29 @@
+/*
+ * 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 { Component, Inventory } from './types';
+
+export class StaticInventory implements Inventory {
+  constructor(private components: Component[]) {}
+
+  list(): Promise<Array<Component>> {
+    return Promise.resolve([...this.components]);
+  }
+
+  item(id: string): Promise<Component | undefined> {
+    return this.list().then(items => items.find(i => i.id === id));
+  }
+}

plugins/inventory-backend/src/inventory/index.ts

@@ -0,0 +1,19 @@
+/*
+ * 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.
+ */
+
+export * from './AggregatorInventory';
+export * from './StaticInventory';
+export * from './types';

plugins/inventory-backend/src/inventory/types.ts

@@ -0,0 +1,24 @@
+/*
+ * 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.
+ */
+
+export type Component = {
+  id: string;
+};
+
+export type Inventory = {
+  list: () => Promise<Component[]>;
+  item: (id: string) => Promise<Component | undefined>;
+};

plugins/inventory-backend/src/run.ts

@@ -0,0 +1,34 @@
+/*
+ * 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 { getRootLogger } from '@backstage/backend-common';
+import { startServer } from './service/server';
+
+startServer({
+  port: process.env.PLUGIN_PORT ? Number(process.env.PLUGIN_PORT) : 3003,
+  enableCors: process.env.PLUGIN_CORS
+    ? Boolean(process.env.PLUGIN_CORS)
+    : false,
+  logger: getRootLogger(),
+}).catch(err => {
+  getRootLogger().error(err);
+  process.exit(1);
+});
+
+process.on('SIGINT', () => {
+  getRootLogger().info('CTRL+C pressed; exiting.');
+  process.exit(0);
+});

plugins/inventory-backend/src/service/application.ts

@@ -0,0 +1,51 @@
+/*
+ * 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 {
+  errorHandler,
+  notFoundHandler,
+  requestLoggingHandler,
+} from '@backstage/backend-common';
+import compression from 'compression';
+import cors from 'cors';
+import express from 'express';
+import helmet from 'helmet';
+import { Logger } from 'winston';
+import { createRouter } from './router';
+
+export interface ApplicationOptions {
+  enableCors: boolean;
+  logger: Logger;
+}
+
+export async function createApplication(
+  options: ApplicationOptions,
+): Promise<express.Application> {
+  const app = express();
+
+  app.use(helmet());
+  if (options.enableCors) {
+    app.use(cors());
+  }
+  app.use(compression());
+  app.use(express.json());
+  app.use(requestLoggingHandler());
+  app.use('/', await createRouter({ logger: options.logger }));
+  app.use(notFoundHandler());
+  app.use(errorHandler());
+
+  return app;
+}

plugins/inventory-backend/src/service/router.ts

@@ -0,0 +1,61 @@
+/*
+ * 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 express from 'express';
+import { Logger } from 'winston';
+import { AggregatorInventory, StaticInventory } from '../inventory';
+
+export interface RouterOptions {
+  logger: Logger;
+}
+
+export async function createRouter(
+  options: RouterOptions,
+): Promise<express.Router> {
+  const logger = options.logger.child({ plugin: 'inventory' });
+
+  const inventory = new AggregatorInventory();
+  inventory.enlist(
+    new StaticInventory([
+      { id: 'component1' },
+      { id: 'component2' },
+      { id: 'component3' },
+      { id: 'component4' },
+    ]),
+  );
+
+  const router = express.Router();
+  router
+    .get('/', async (req, res) => {
+      const components = await inventory.list();
+      res.status(200).send(components);
+    })
+    .get('/:id', async (req, res) => {
+      const { id } = req.params;
+      const component = await inventory.item(id);
+      if (component) {
+        res.status(200).send(component);
+      } else {
+        res.status(404).send();
+      }
+    });
+
+  const app = express();
+  app.set('logger', logger);
+  app.use('/', router);
+
+  return app;
+}

plugins/inventory-backend/src/service/server.ts

@@ -0,0 +1,48 @@
+/*
+ * 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 { Server } from 'http';
+import { Logger } from 'winston';
+import { createApplication } from './application';
+
+export interface ServerOptions {
+  port: number;
+  enableCors: boolean;
+  logger: Logger;
+}
+
+export async function startServer(options: ServerOptions): Promise<Server> {
+  const logger = options.logger.child({ service: 'inventory-backend' });
+
+  logger.debug('Creating application...');
+  const app = await createApplication({
+    enableCors: options.enableCors,
+    logger,
+  });
+
+  logger.debug('Starting application server...');
+  return await new Promise((resolve, reject) => {
+    const server = app.listen(options.port, (err?: Error) => {
+      if (err) {
+        reject(err);
+        return;
+      }
+
+      logger.info(`Listening on port ${options.port}`);
+      resolve(server);
+    });
+  });
+}

plugins/inventory-backend/src/setupTests.ts

@@ -13,3 +13,5 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
+require('jest-fetch-mock').enableMocks();

plugins/inventory-backend/tsconfig.json

@@ -10,6 +10,7 @@
     "target": "es5",
     "module": "commonjs",
     "esModuleInterop": true,
+    "lib": ["es2019"],
     "types": ["node", "jest"]
   }
 }

yarn.lock

@@ -16680,11 +16680,16 @@ prepend-http@^1.0.0, prepend-http@^1.0.1:
   resolved "https://registry.npmjs.org/prepend-http/-/prepend-http-1.0.4.tgz#d4f4562b0ce3696e41ac52d0e002e57a635dc6dc"
   integrity sha1-1PRWKwzjaW5BrFLQ4ALlemNdxtw=
 
-prettier@^1.16.4, prettier@^1.18.2, prettier@^1.19.1:
+prettier@^1.16.4, prettier@^1.18.2:
   version "1.19.1"
   resolved "https://registry.npmjs.org/prettier/-/prettier-1.19.1.tgz#f7d7f5ff8a9cd872a7be4ca142095956a60797cb"
   integrity sha512-s7PoyDv/II1ObgQunCbB9PdLmUcBZcnWOcxDh7O0N/UwDEsHyqkW+Qh28jW+mVuCdx7gLB0BotYI1Y6uI9iyew==
 
+prettier@^2.0.5:
+  version "2.0.5"
+  resolved "https://registry.npmjs.org/prettier/-/prettier-2.0.5.tgz#d6d56282455243f2f92cc1716692c08aa31522d4"
+  integrity sha512-7PtVymN48hGcO4fGjybyBSIWDsLU4H4XlvOHfq91pz9kkGlonzwTfYkaIEwiRg/dAJF9YlbsduBAgtYLi+8cFg==
+
 pretty-bytes@5.3.0, pretty-bytes@^5.1.0:
   version "5.3.0"
   resolved "https://registry.npmjs.org/pretty-bytes/-/pretty-bytes-5.3.0.tgz#f2849e27db79fb4d6cfe24764fc4134f165989f2"