JavaScript (v3): Update utils. (awsdocs#6950)

- Update the getUniqueName util to throw an error if a prefix is not passed in.
- Add a validateArgs util for checking parseArg options marked as required.

javascriptv3/example_code/libs/tests/util-string.unit.test.js

@@ -17,10 +17,10 @@ describe("util-string", () => {
       expect(u1).not.toEqual(u2);
     });
 
-    it("should return undefined if a falsy value is passed in", () => {
-      expect(getUniqueName()).toBeUndefined();
-      expect(getUniqueName("")).toBeUndefined();
-      expect(getUniqueName(0)).toBeUndefined();
+    it("should throw an error if a falsy value is passed in for the prefix", () => {
+      expect(() => getUniqueName()).toThrowError();
+      expect(() => getUniqueName("")).toThrowError();
+      expect(() => getUniqueName(0)).toThrowError();
     });
   });
 

javascriptv3/example_code/libs/utils/util-node.js

@@ -12,3 +12,32 @@ export const setEnv = (/** @type {string} */ key, value) => {
  * @param {string | URL} fileUrl
  */
 export const isMain = (fileUrl) => process.argv[1] === fileURLToPath(fileUrl);
+
+/**
+ * @typedef {import("node:util").ParseArgsConfig} ParseArgsConfig
+ * @typedef {ReturnType<import("node:util").parseArgs>} ParsedResults
+ *
+ * @param {import("node:util").ParseArgsConfig} config
+ * @param {ParsedResults} results
+ * @returns {{ errors: string[] | null }}
+ */
+export const validateArgs = (config, results) => {
+  if (!config.options) {
+    return {};
+  }
+
+  /** @type {string[] | null} */
+  let errors = null;
+
+  for (const option in config.options) {
+    const optionRequired = config.options[option]?.required;
+    const optionPresent = Object.hasOwn(results.values, option);
+
+    if (optionRequired && !optionPresent) {
+      errors = errors ?? [];
+      errors.push(`Missing required argument "${option}".`);
+    }
+
+    return { errors };
+  }
+};

javascriptv3/example_code/libs/utils/util-string.js

@@ -3,14 +3,18 @@
 import { v4 as uuidv4 } from "uuid";
 
 /**
- * @param {string} name
+ * @param {string} prefix
  */
-export const getUniqueName = (name) => {
-  if (!name) {
-    return;
+export const getUniqueName = (prefix) => {
+  class GetUniqueNameError extends Error {
+    name = GetUniqueNameError.name;
   }
 
-  return `${name.toLowerCase()}-${uuidv4()}`;
+  if (!prefix) {
+    throw new GetUniqueNameError("Prefix is missing.");
+  }
+
+  return `${prefix.toLowerCase()}-${uuidv4()}`;
 };
 
 /**