feat: generate keypair and add to .env if one doesn't exist

src/index.test.ts

@@ -1,14 +1,17 @@
 import { before, describe, test } from "node:test";
-import { getKeypairFromEnvironment, getKeypairFromFile } from "./index";
+import {
+  getKeypairFromEnvironment,
+  getKeypairFromFile,
+  addKeypairToEnvironment,
+} from "./index";
 
 import { Keypair } from "@solana/web3.js";
 import assert from "node:assert/strict";
 import base58 from "bs58";
-import dotenv from "dotenv";
 import { exec as execForOldPeople } from "child_process";
 import { promisify } from "util";
-import { unlinkSync } from "node:fs";
-import { writeFile } from "node:fs/promises";
+import { writeFile, unlink } from "node:fs/promises";
+import dotenv from "dotenv";
 
 const exec = promisify(execForOldPeople);
 
@@ -72,31 +75,57 @@ describe("getKeypairFromEnvironment", () => {
     await getKeypairFromEnvironment(TEST_ENV_VAR_BASE58);
   });
 
+  test("throws a nice error if the env var doesn't exist", async () => {
+    assert.rejects(async () => getKeypairFromEnvironment("MISSING_ENV_VAR"), {
+      message: `Please set 'MISSING_ENV_VAR' in environment.`,
+    });
+  });
+
+  test("throws a nice error if the value of the env var isn't valid", async () => {
+    assert.rejects(
+      async () => getKeypairFromEnvironment("TEST_ENV_VAR_WITH_BAD_VALUE"),
+      {
+        message: `Invalid secret key in environment variable 'TEST_ENV_VAR_WITH_BAD_VALUE'!`,
+      },
+    );
+  });
+});
+
+describe("addKeypairToEnvironment", () => {
+  let TEST_ENV_VAR_ARRAY_OF_NUMBERS = "TEST_ENV_VAR_ARRAY_OF_NUMBERS";
+
+  before(async () => {
+    const randomKeypair = Keypair.generate();
+
+    process.env[TEST_ENV_VAR_ARRAY_OF_NUMBERS] = JSON.stringify(
+      Object.values(randomKeypair.secretKey),
+    );
+  });
+
   test("generates new keypair and writes to env if variable doesn't exist", async () => {
-    // Returns a new keypair and writes it to the .env file
-    const newKeypair = await getKeypairFromEnvironment("MISSING_ENV_VAR");
+    // Generates new keypair and writes it to the .env file
+    addKeypairToEnvironment("TEMP_KEYPAIR");
     // Load the .env file
     dotenv.config();
     // Get the secret from the .env file
-    const secretKeyString = process.env["MISSING_ENV_VAR"];
+    const secretKeyString = process.env["TEMP_KEYPAIR"];
 
     if (!secretKeyString) {
-      throw new Error("MISSING_ENV_VAR not found in environment");
+      throw new Error("TEMP_KEYPAIR not found in environment");
     }
     const decodedSecretKey = Uint8Array.from(JSON.parse(secretKeyString));
     const envKeypair = Keypair.fromSecretKey(decodedSecretKey);
 
-    assert.deepStrictEqual(newKeypair.secretKey, envKeypair.secretKey);
+    assert.ok(envKeypair.secretKey);
 
-    // delete the .env file
-    unlinkSync(".env");
+    unlink(".env");
   });
 
-  test("throws a nice error if the value of the env var isn't valid", async () => {
+  test("throws a nice error if the env var already exists", async () => {
     assert.rejects(
-      async () => getKeypairFromEnvironment("TEST_ENV_VAR_WITH_BAD_VALUE"),
+      async () => addKeypairToEnvironment(TEST_ENV_VAR_ARRAY_OF_NUMBERS),
       {
-        message: `Invalid secret key in environment variable 'TEST_ENV_VAR_WITH_BAD_VALUE'!`,
+        message: `'TEST_ENV_VAR_ARRAY_OF_NUMBERS' already exists in environment.`,
       },
     );
   });

src/index.ts

@@ -1,8 +1,8 @@
 import { Keypair } from "@solana/web3.js";
 import base58 from "bs58";
-import fs from "fs";
 import path from "path";
 import { readFile } from "fs/promises";
+import { appendFileSync } from "node:fs";
 const log = console.log;
 
 // Default value from Solana CLI
@@ -46,13 +46,7 @@ export const getKeypairFromFile = async (filepath?: string) => {
 export const getKeypairFromEnvironment = (variableName: string) => {
   const secretKeyString = process.env[variableName];
   if (!secretKeyString) {
-    // Generate a new keypair if one doesn't exist and add it to a `.env` file
-    const keypair = Keypair.generate();
-    fs.appendFileSync(
-      ".env",
-      `\n${variableName}=${JSON.stringify(Array.from(keypair.secretKey))}`,
-    );
-    return keypair;
+    throw new Error(`Please set '${variableName}' in environment.`);
   }
 
   // Try the shorter base58 format first
@@ -79,3 +73,17 @@ export const getKeypairFromEnvironment = (variableName: string) => {
   }
   return Keypair.fromSecretKey(decodedSecretKey);
 };
+
+export const addKeypairToEnvironment = (variableName: string) => {
+  const secretKeyString = process.env[variableName];
+  if (!secretKeyString) {
+    // Generate a new keypair if one doesn't exist and add it to a `.env` file
+    const keypair = Keypair.generate();
+    appendFileSync(
+      ".env",
+      `\n${variableName}=${JSON.stringify(Array.from(keypair.secretKey))}`,
+    );
+  } else {
+    throw new Error(`'${variableName}' already exists in environment.`);
+  }
+};