@jsenv/core/src/dev/user_agent.js

Tool to develop, test and build js projects

import { memoizeByFirstArgument } from "@jsenv/utils/src/memoize/memoize_by_first_argument.js";

import { requireFromJsenv } from "@jsenv/core/src/helpers/require_from_jsenv.js";

export const parseUserAgentHeader = memoizeByFirstArgument((userAgent) => {
  if (userAgent.includes("node-fetch/")) {
    // it's not really node and conceptually we can't assume the node version
    // but good enough for now
    return {
      runtimeName: "node",
      runtimeVersion: process.version.slice(1),
    };
  }
  const UA = requireFromJsenv("@financial-times/polyfill-useragent-normaliser");
  const { ua } = new UA(userAgent);
  const { family, major, minor, patch } = ua;
  return {
    runtimeName: family.toLowerCase(),
    runtimeVersion:
      family === "Other" ? "unknown" : `${major}.${minor}${patch}`,
  };
});