feat: add fromEnv() helper for consistent env ops across Node/Bun/Deno (#50)

Author: jeff-mccoy

.github/workflows/node.js.yml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        node-version: [18, latest]
+        node-version: [18, 20, latest]
     steps:
       - uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11 # v4.1.1
       - name: Use Node.js ${{ matrix.node-version }}

src/helpers.test.ts

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: 2023-Present The Kubernetes Fluent Client Authors
+
+import { describe, expect, test } from "@jest/globals";
+
+import { fromEnv } from "./helpers";
+
+describe("helpers", () => {
+  test("fromEnv for NodeJS", () => {
+    expect(() => {
+      fromEnv("MY_MISSING_ENV_VAR");
+    }).toThrowError("Environment variable MY_MISSING_ENV_VAR is not set");
+
+    process.env.MY_ENV_VAR = "my-value";
+    expect(fromEnv("MY_ENV_VAR")).toEqual("my-value");
+    delete process.env.MY_ENV_VAR;
+  });
+});

src/helpers.ts

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: 2023-Present The Kubernetes Fluent Client Authors
+
+declare const Deno: {
+  env: {
+    get(name: string): string | undefined;
+  };
+};
+
+/**
+ * Get an environment variable (Node, Deno or Bun), or throw an error if it's not set.
+ *
+ * @example
+ * const value = fromEnv("MY_ENV_VAR");
+ * console.log(value);
+ * // => "my-value"
+ *
+ * @example
+ * const value = fromEnv("MY_MISSING_ENV_VAR");
+ * // => Error: Environment variable MY_MISSING_ENV_VAR is not set
+ *
+ * @param name The name of the environment variable to get.
+ * @returns The value of the environment variable.
+ * @throws An error if the environment variable is not set.
+ */
+export function fromEnv(name: string): string {
+  let envValue: string | undefined;
+
+  // Check for Node.js or Bun
+  if (typeof process !== "undefined" && typeof process.env !== "undefined") {
+    envValue = process.env[name];
+  }
+  // Check for Deno
+  else if (typeof Deno !== "undefined") {
+    envValue = Deno.env.get(name);
+  }
+  // Otherwise, throw an error
+  else {
+    throw new Error("Unknown runtime environment");
+  }
+
+  if (typeof envValue === "undefined") {
+    throw new Error(`Environment variable ${name} is not set`);
+  }
+
+  return envValue;
+}

src/index.ts

@@ -25,3 +25,5 @@ export { GenericKind } from "./types";
 export * from "./types";
 
 export * as K8sClientNode from "@kubernetes/client-node";
+
+export { fromEnv } from "./helpers";