Implementation of caching functionality for setup-go action (#228)

src/cache-restore.ts

@@ -0,0 +1,62 @@
+import * as cache from '@actions/cache';
+import * as core from '@actions/core';
+import * as glob from '@actions/glob';
+import path from 'path';
+import fs from 'fs';
+
+import {State, Outputs} from './constants';
+import {PackageManagerInfo} from './package-managers';
+import {getCacheDirectoryPath, getPackageManagerInfo} from './cache-utils';
+
+export const restoreCache = async (
+  packageManager: string,
+  cacheDependencyPath?: string
+) => {
+  const packageManagerInfo = await getPackageManagerInfo(packageManager);
+  const platform = process.env.RUNNER_OS;
+  const versionSpec = core.getInput('go-version');
+
+  const cachePaths = await getCacheDirectoryPath(packageManagerInfo);
+
+  const dependencyFilePath = cacheDependencyPath
+    ? cacheDependencyPath
+    : findDependencyFile(packageManagerInfo);
+  const fileHash = await glob.hashFiles(dependencyFilePath);
+
+  if (!fileHash) {
+    throw new Error(
+      'Some specified paths were not resolved, unable to cache dependencies.'
+    );
+  }
+
+  const primaryKey = `setup-go-${platform}-go-${versionSpec}-${fileHash}`;
+  core.debug(`primary key is ${primaryKey}`);
+
+  core.saveState(State.CachePrimaryKey, primaryKey);
+
+  const cacheKey = await cache.restoreCache(cachePaths, primaryKey);
+  core.setOutput(Outputs.CacheHit, Boolean(cacheKey));
+
+  if (!cacheKey) {
+    core.info(`Cache is not found`);
+    return;
+  }
+
+  core.saveState(State.CacheMatchedKey, cacheKey);
+  core.info(`Cache restored from key: ${cacheKey}`);
+};
+
+const findDependencyFile = (packageManager: PackageManagerInfo) => {
+  let dependencyFile = packageManager.dependencyFilePattern;
+  const workspace = process.env.GITHUB_WORKSPACE!;
+  const rootContent = fs.readdirSync(workspace);
+
+  const goSumFileExists = rootContent.includes(dependencyFile);
+  if (!goSumFileExists) {
+    throw new Error(
+      `Dependencies file is not found in ${workspace}. Supported file pattern: ${dependencyFile}`
+    );
+  }
+
+  return path.join(workspace, dependencyFile);
+};