Add start script and show env vars when you run it

Author: luckysori

new_project/.gitignore

@@ -1 +1,2 @@
 yarn-error.log
+node_modules/

new_project/package.json

@@ -2,7 +2,13 @@
   "name": "new_project",
   "version": "0.1.0",
   "private": true,
+  "main": "index.js",
+  "scripts": {
+    "start": "DOTENV_CONFIG_PATH=$HOME/.create-comit-app/env node -r dotenv/config ./src/index.js"
+  },
   "dependencies": {
-    "comit-sdk": "^0.7.0"
+    "comit-sdk": "^0.7.1",
+    "dotenv": "^8.2.0",
+    "readline-sync": "^1.4.10"
   }
 }

new_project/src/index.js

@@ -0,0 +1,46 @@
+const fs = require("fs");
+
+const configPath = process.env.DOTENV_CONFIG_PATH;
+
+if (fs.existsSync(configPath)) {
+  console.log("Environment configuration:");
+
+  // Bitcoin HD keys with address funded during environment set-up.
+  // Used to initialize Bitcoin wallets with funds.
+  console.log("Bitcoin HD keys:");
+  console.log("1. ", process.env.BITCOIN_HD_KEY_0);
+  console.log("2. ", process.env.BITCOIN_HD_KEY_1);
+
+  // The URI of the regtest Bitcoin node created during environment set-up.
+  // Used to initialize Bitcoin wallets connected to the correct local network.
+  console.log("Bitcoin node P2P URI: ", process.env.BITCOIN_P2P_URI);
+
+  // Ethereum private keys with address funded during environment set-up.
+  // Used to initialize Ethereum wallets with funds.
+  console.log("Ethereum private keys:");
+  console.log("1. ", process.env.ETHEREUM_KEY_0);
+  console.log("2. ", process.env.ETHEREUM_KEY_1);
+
+  // The URL for the HTTP API of the regtest Ethereum node created during environment set-up.
+  // Used to initialize Ethereum wallets connected to the correct local network.
+  console.log("Ethereum node HTTP URL: ", process.env.ETHEREUM_NODE_HTTP_URL);
+
+  // The contract address of the ERC20 token deployed on the regtest network during environment set-up.
+  // Used to identify the ERC20 token when performing swaps.
+  console.log(
+    "ERC20 token contract address: ",
+    process.env.ERC20_CONTRACT_ADDRESS
+  );
+
+  // HTTP API URLs for the instances of cnd created during environment set-up.
+  // Used to interact with said instances of cnd. In particular, it allows for
+  // instantiating `ComitClient`s when using `comit-sdk`.
+  console.log("cnd HTTP API URLs:");
+  console.log("1. ", process.env.HTTP_URL_CND_0);
+  console.log("2. ", process.env.HTTP_URL_CND_1);
+} else {
+  console.log(
+    "Could not find file %s. Did you run `yarn create comit-app start-env`?",
+    configPath
+  );
+}