From c2930c3b2cf88e62cdc83de246d7700954a277e7 Mon Sep 17 00:00:00 2001
From: Johan Haals <johan.haals@gmail.com>
Date: Fri, 21 Jan 2022 14:15:58 +0100
Subject: [PATCH] manifest: add getReleaseBy methods

Signed-off-by: Johan Haals <johan.haals@gmail.com>
---
 packages/release-manifest/src/index.ts        |  3 +
 .../release-manifest/src/manifest.test.ts     | 52 +++++++++++-
 packages/release-manifest/src/manifest.ts     | 82 ++++++++++++-------
 3 files changed, 104 insertions(+), 33 deletions(-)

diff --git a/packages/release-manifest/src/index.ts b/packages/release-manifest/src/index.ts
index 099b146e78..fa05520855 100644
--- a/packages/release-manifest/src/index.ts
+++ b/packages/release-manifest/src/index.ts
@@ -19,3 +19,6 @@
  *
  * @packageDocumentation
  */
+
+export { getByVersion, getByReleaseLine } from './manifest';
+export type { ReleaseManifest } from './manifest';
diff --git a/packages/release-manifest/src/manifest.test.ts b/packages/release-manifest/src/manifest.test.ts
index 0c2005d1a8..a5c7235036 100644
--- a/packages/release-manifest/src/manifest.test.ts
+++ b/packages/release-manifest/src/manifest.test.ts
@@ -1,9 +1,53 @@
-import { getRelease } from './manifest';
+/*
+ * Copyright 2020 The Backstage Authors
+ *
+ * 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 { setupRequestMockHandlers } from '@backstage/test-utils';
+import { getByVersion } from './manifest';
+import { setupServer } from 'msw/node';
+import { rest } from 'msw';
 
 describe('Get Packages', () => {
+  const worker = setupServer();
+  setupRequestMockHandlers(worker);
+
   it('should return a list of packages in a release', async () => {
-    const pkgs = await getRelease('1.0.0');
-    console.log(pkgs);
-    expect(pkgs.size).toBe(2);
+    worker.use(
+      rest.get('*/v1/releases/0.0.0', (_, res, ctx) =>
+        res(
+          ctx.status(200),
+          ctx.json({
+            packages: [{ name: '@backstage/core', version: '1.2.3' }],
+          }),
+        ),
+      ),
+      rest.get('*/v1/releases/999.0.1', (_, res, ctx) =>
+        res(ctx.status(404), ctx.json({})),
+      ),
+    );
+
+    const pkgs = await getByVersion({ version: '0.0.0' });
+    expect(pkgs.packages).toEqual([
+      {
+        name: '@backstage/core',
+        version: '1.2.3',
+      },
+    ]);
+
+    await expect(getByVersion({ version: '999.0.1' })).rejects.toThrow(
+      'No release found for 999.0.1 version',
+    );
   });
 });
diff --git a/packages/release-manifest/src/manifest.ts b/packages/release-manifest/src/manifest.ts
index 07e3ec7cb7..378ff41b7a 100644
--- a/packages/release-manifest/src/manifest.ts
+++ b/packages/release-manifest/src/manifest.ts
@@ -14,44 +14,68 @@
  * limitations under the License.
  */
 
+import fetch from 'node-fetch';
+
+const VERSIONS_DOMAIN = 'https://versions.backstage.io';
+
 /**
- * Mapping between a Backstage release and individual package versions.
+ * Contains mapping between Backstage release and package versions.
  * @public
  */
-import { resolvePackagePath } from '@backstage/backend-common';
-import fs from 'fs-extra';
-import path from 'path';
-
-const RELEASE_DIR = resolvePackagePath(
-  '@backstage/release-manifest',
-  'releases',
-);
-
 export type ReleaseManifest = {
-  packages: Map<string, string>;
+  packages: { name: string; version: string }[];
 };
 
-export async function getRelease(version: string): Promise<ReleaseManifest> {
-  const pkgs = new Map<string, string>();
-  try {
-    const content = await fs.readFile(path.resolve(RELEASE_DIR, `${version}`));
-    for (const line of content.toString().split('\n')) {
-      const [pkg, version] = line.split('=');
-      pkgs.set(pkg, version);
-    }
-  } catch (e) {
-    throw new Error(`No release found for ${version} version`);
+/**
+ * Options for getByVersion.
+ */
+export type GetByVersionOptions = {
+  version: string;
+};
+
+/**
+ * Returns a release manifest based on supplied version.
+ * @public
+ */
+export async function getByVersion(
+  options: GetByVersionOptions,
+): Promise<ReleaseManifest> {
+  const url = `${VERSIONS_DOMAIN}/v1/releases/${options.version}`;
+  const response = await fetch(url);
+  if (response.status === 404) {
+    throw new Error(`No release found for ${options.version} version`);
   }
-  return { packages: pkgs };
+  if (response.status !== 200) {
+    throw new Error(
+      `Unexpected response status ${response.status} when fetching release from ${url}.`,
+    );
+  }
+  return await response.json();
 }
 
-export type ReleaseList = {
-  items: {
-    version: string;
-  }[];
+/**
+ * Options for getByReleaseLine.
+ */
+export type GetByReleaseLineOptions = {
+  releaseLine: string;
 };
 
-export async function listReleases(): Promise<ReleaseList> {
-  const files = await fs.readdir(RELEASE_DIR);
-  return { items: files.map(file => ({ version: file })) };
+/**
+ * Returns a release manifest based on supplied release line.
+ * @public
+ */
+export async function getByReleaseLine(
+  options: GetByReleaseLineOptions,
+): Promise<ReleaseManifest> {
+  const url = `${VERSIONS_DOMAIN}/v1/tags/${options.releaseLine}`;
+  const response = await fetch(url);
+  if (response.status === 404) {
+    throw new Error(`No '${options.releaseLine}' release line found`);
+  }
+  if (response.status !== 200) {
+    throw new Error(
+      `Unexpected response status ${response.status} when fetching release from ${url}.`,
+    );
+  }
+  return await response.json();
 }