Extract some commonly used methods to a shared file

build/utils/build-common.js

@@ -0,0 +1,55 @@
+const fs = require('fs').promises;
+const fsConstants = require('fs').constants;
+
+const ExitCodes = {
+    "RequestFailure": 1,
+    "ParseFailure": 2,
+    "ExecFailure": 3,
+    "IOFailure": 4,
+};
+exports.ExitCodes = ExitCodes;
+
+async function ensureDir(dirPath) {
+    try {
+        await fs.access(dirPath, fsConstants.R_OK | fsConstants.W_OK);
+    } catch (err) {
+        console.log(`    Folder at path ${dirPath} does not exit or is inaccessible, attempting to create...`);
+        await fs.mkdir(dirPath);
+    }
+}
+exports.ensureDir = ensureDir;
+
+async function clearDir(rootPath) {
+    try {
+        const pathStat = await fs.stat(rootPath);
+        if (!pathStat.isDirectory()) {
+            return;
+        }
+
+        const removeDir = async (dirPath) => {
+            const dirFiles = await fs.readdir(dirPath);
+            for (let entryName of dirFiles) {
+                if (entryName === "." || entryName === "..") {
+                    continue;
+                }
+
+                const entryPath = `${dirPath}/${entryName}`;
+                const entryStat = await fs.stat(entryPath);
+                if (entryStat.isDirectory()) {
+                    await removeDir(entryPath);
+                    await fs.rmdir(entryPath);
+                }
+                else if (entryStat.isFile()) {
+                    await fs.unlink(entryPath);
+                }
+            }
+        };
+
+        await removeDir(rootPath);
+    } catch (err) {
+        console.error(`    Error clearing a folder at ${rootPath}: ` + err);
+        process.exitCode = ExitCodes.IOFailure;
+        return;
+    }
+}
+exports.clearDir = clearDir;