@gnosis.pm/truffle-nice-tools/network/extract-network-info.js

A set CLI tools that make truffle development feel more elegant.

#!/usr/bin/env node
const ora = require("ora");
const fs = require("fs");
const path = require("path");
const _ = require("lodash");

const dir = path.join("build", "contracts");

module.exports = () => {
  const spinner = ora().start();
  try {
    const dirFiles = fs.readdirSync(dir);

    Promise.all(
      dirFiles.filter(fname => fname.endsWith(".json")).map(
        fname =>
          new Promise((resolve, _reject) => {
            fs.readFile(path.join(dir, fname), (err, data) => {
              if (err) throw err;
              resolve([fname.slice(0, -5), JSON.parse(data)["networks"]]);
            });
          })
      )
    ).then(nameNetworkPairs => {
      fs.writeFileSync(
        "networks.json",
        JSON.stringify(
          _.fromPairs(
            nameNetworkPairs.filter(([_name, nets]) => !_.isEmpty(nets))
          ),
          null,
          2
        )
      );
      spinner.stop();
    });
  } catch (err) {
    if (err.code === "ENOENT") {
      fs.writeFileSync("networks.json", "{}");
      console.log('Didn\'t find any networks. Creating an empty file');
      spinner.stop();
    } else {
      throw err;
    }
  }
};