packages/cli: move config loading to separate config-loader package

packages/cli/package.json

@@ -30,6 +30,7 @@
   },
   "dependencies": {
     "@backstage/config": "^0.1.1-alpha.6",
+    "@backstage/config-loader": "^0.1.1-alpha.6",
     "@hot-loader/react-dom": "^16.13.0",
     "@lerna/package-graph": "^3.18.5",
     "@lerna/project": "^3.18.0",

packages/cli/src/commands/app/build.ts

@@ -16,7 +16,7 @@
 
 import { buildBundle } from '../../lib/bundler';
 import { Command } from 'commander';
-import { loadConfig } from '../../lib/app-config';
+import { loadConfig } from '@backstage/config-loader';
 
 export default async (cmd: Command) => {
   await buildBundle({

packages/cli/src/commands/app/serve.ts

@@ -16,7 +16,7 @@
 
 import { Command } from 'commander';
 import { serveBundle } from '../../lib/bundler';
-import { loadConfig } from '../../lib/app-config';
+import { loadConfig } from '@backstage/config-loader';
 
 export default async (cmd: Command) => {
   const waitForExit = await serveBundle({

packages/cli/src/commands/plugin/serve.ts

@@ -16,7 +16,7 @@
 
 import { Command } from 'commander';
 import { serveBundle } from '../../lib/bundler';
-import { loadConfig } from '../../lib/app-config';
+import { loadConfig } from '@backstage/config-loader';
 
 export default async (cmd: Command) => {
   const waitForExit = await serveBundle({

packages/config-loader/.eslintrc.js

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

packages/config-loader/README.md

@@ -0,0 +1,12 @@
+# @backstage/config-loader
+
+This package provides config loading functionality used by the backend, and CLI.
+
+## Installation
+
+Do not install this package directly, it is an internal package used by [@backstage/cli](https://www.npmjs.com/package/@backstage/cli), and [@backstage/backend-common](https://www.npmjs.com/package/@backstage/backend-common). Depend on either of those instead.
+
+## Documentation
+
+- [Backstage Readme](https://github.com/spotify/backstage/blob/master/README.md)
+- [Backstage Documentation](https://github.com/spotify/backstage/blob/master/docs/README.md)

packages/config-loader/package.json

@@ -0,0 +1,43 @@
+{
+  "name": "@backstage/config-loader",
+  "description": "Config loading functionality used by Backstage backend, and CLI",
+  "version": "0.1.1-alpha.6",
+  "private": false,
+  "publishConfig": {
+    "access": "public"
+  },
+  "homepage": "https://backstage.io",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/spotify/backstage",
+    "directory": "packages/config-loader"
+  },
+  "keywords": [
+    "backstage"
+  ],
+  "license": "Apache-2.0",
+  "main": "dist/index.esm.js",
+  "main:src": "src/index.ts",
+  "types": "src/index.ts",
+  "scripts": {
+    "build": "backstage-cli plugin:build",
+    "lint": "backstage-cli lint",
+    "test": "backstage-cli test",
+    "prepack": "backstage-cli prepack",
+    "postpack": "backstage-cli postpack",
+    "clean": "backstage-cli clean"
+  },
+  "dependencies": {
+    "@backstage/config": "^0.1.1-alpha.6",
+    "fs-extra": "^9.0.0",
+    "yaml": "^1.9.2"
+  },
+  "devDependencies": {
+    "@backstage/cli": "^0.1.1-alpha.6",
+    "@types/jest": "^25.2.2",
+    "@types/node": "^12.0.0"
+  },
+  "files": [
+    "dist/**/*.{js,d.ts}"
+  ]
+}

packages/config-loader/src/index.ts

@@ -14,4 +14,5 @@
  * limitations under the License.
  */
 
-export { loadConfig } from './loaders';
+export { loadConfig } from './loader';
+export type { LoadConfigOptions } from './types';

packages/config-loader/src/loader.ts

@@ -16,20 +16,23 @@
 
 import fs from 'fs-extra';
 import yaml from 'yaml';
+import { resolve as resolvePath } from 'path';
 import { AppConfig } from '@backstage/config';
-import { paths } from '../paths';
-
-type LoadConfigOptions = {
-  // Config path, defaults to app-config.yaml in project root
-  configPath?: string;
-};
+import { findRootPath } from './paths';
+import { LoadConfigOptions } from './types';
 
 export async function loadConfig(
   options: LoadConfigOptions = {},
 ): Promise<AppConfig[]> {
   // TODO: We'll want this to be a bit more elaborate, probably adding configs for
   //       specific env, and maybe local config for plugins.
-  const { configPath = paths.resolveTargetRoot('app-config.yaml') } = options;
+  let { configPath } = options;
+  if (!configPath) {
+    configPath = resolvePath(
+      findRootPath(fs.realpathSync(process.cwd())),
+      'app-config.yaml',
+    );
+  }
 
   try {
     const configYaml = await fs.readFile(configPath, 'utf8');

packages/config-loader/src/paths.ts

@@ -0,0 +1,57 @@
+/*
+ * 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 fs from 'fs-extra';
+import { dirname, resolve as resolvePath } from 'path';
+
+/**
+ * Looks for a package.json that has name: "root" to identify the root of the monorepo
+ *
+ * This is a copy of the same function in the CLI
+ */
+export function findRootPath(topPath: string): string {
+  let path = topPath;
+
+  // Some sanity check to avoid infinite loop
+  for (let i = 0; i < 1000; i++) {
+    const packagePath = resolvePath(path, 'package.json');
+    const exists = fs.pathExistsSync(packagePath);
+    if (exists) {
+      try {
+        const data = fs.readJsonSync(packagePath);
+        if (data.name === 'root' || data.name.includes('backstage-e2e')) {
+          return path;
+        }
+      } catch (error) {
+        throw new Error(
+          `Failed to parse package.json file while searching for root, ${error}`,
+        );
+      }
+    }
+
+    const newPath = dirname(path);
+    if (newPath === path) {
+      throw new Error(
+        `No package.json with name "root" found as a parent of ${topPath}`,
+      );
+    }
+    path = newPath;
+  }
+
+  throw new Error(
+    `Iteration limit reached when searching for root package.json at ${topPath}`,
+  );
+}

packages/config-loader/src/types.ts

@@ -0,0 +1,20 @@
+/*
+ * 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 LoadConfigOptions = {
+  // Config path, defaults to app-config.yaml in project root
+  configPath?: string;
+};