devebot/lib/utils/proxy.js

Nodejs Microservice Framework

"use strict";

const toPath = require("lodash/toPath");
const nameIndexOf = {
  get: 1,
  set: 1,
  has: 1,
  defineProperty: 1,
  deleteProperty: 1,
  enumerate: 1,
  getOwnPropertyDescriptor: 1
};
const trapNames = ["apply", "construct", "getPrototypeOf", "setPrototypeOf", "isExtensible", "preventExtensions", "ownKeys"].concat(Object.keys(nameIndexOf));
function BeanProxy(target, handler, opts = {}) {
  function createProxy(beanTarget, path) {
    const pathString = chainify(path);
    const sharedContext = opts.isContextShared ? {
      root: target,
      path
    } : null;
    const wrappedHandler = {};
    for (const trapName of trapNames) {
      const trap = handler[trapName];
      if (isFunction(trap)) {
        const nameIndex = nameIndexOf[trapName];
        wrappedHandler[trapName] = function () {
          const context = opts.isContextShared ? sharedContext : {
            root: target,
            path
          };
          const name = isNumber(nameIndex) ? arguments[nameIndex] : null;
          context.slug = pathString;
          if (isString(name)) {
            context.slug = pathString && pathString + "." + name || name;
          }
          context.wrap = function (wrappedTarget) {
            if (isUndefined(wrappedTarget)) {
              wrappedTarget = isString(name) ? target : {};
            }
            const wrappedPath = isString(name) ? [].concat(path, name) : path;
            return createProxy(wrappedTarget, wrappedPath);
          };
          return trap.apply(context, arguments);
        };
      }
    }
    return new Proxy(beanTarget, wrappedHandler);
  }
  return createProxy(target, extractPath(opts));
}
module.exports = BeanProxy;
function chainify(path) {
  if (isString(path)) return path;
  if (Array.isArray(path)) return path.join(".");
  return null;
}
function extractPath(options) {
  return options && options.path ? toPath(options.path) : [];
}
function isFunction(f) {
  return typeof f === "function";
}
function isNumber(n) {
  return typeof n === "number";
}
function isString(s) {
  return typeof s === "string";
}
function isUndefined(v) {
  return typeof v === "undefined";
}