@batolye/bdk-core/lib/hooks/hooks.service.js

Module to provide core utilities for BulusAtolyesi applications and services

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.rateLimit = rateLimit;
exports.countLimit = countLimit;

var _errors = require("@feathersjs/errors");

var _limiter = require("limiter");

var _debug = _interopRequireDefault(require("debug"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const debug = (0, _debug.default)("batolye:bdk-core:service:hooks");

function rateLimit(options) {
  const limiter = new _limiter.RateLimiter(options.tokensPerInterval, options.interval);
  return function (hook) {
    if (hook.type !== "before") {
      throw new Error(`The 'rateLimit' hook should only be used as a 'before' hook.`);
    }

    const operation = hook.method;
    const service = hook.service.core_name;
    let rateLimit = true;

    if (options.operation && options.operation !== operation) {
      rateLimit = false;
    }

    if (options.service && options.service !== service) {
      rateLimit = false;
    }

    if (rateLimit) {
      debug(limiter.getTokensRemaining() + " remaining token for rateLimit hook on service " + service);

      if (!limiter.tryRemoveTokens(1)) {
        // if exceeded
        throw new _errors.TooManyRequests("Too many requests in a given amount of time (rate limiting) on service " + service, {
          translation: {
            key: "RATE_LIMITING"
          }
        });
      }
    }

    return hook;
  };
}

function countLimit(options) {
  return async function (hook) {
    if (hook.type !== "before") {
      throw new Error(`The 'countLimit' hook should only be used as a 'before' hook.`);
    }

    let app = hook.app;
    const customMax = typeof options.max === "function";
    const max = customMax ? await options.max(hook) : options.max; // -1 means no limit

    if (max >= 0) {
      let count = options.max; // Either we build a count request using a service or the caller has its own count routine

      const customCount = typeof options.count === "function";

      if (!customCount) {
        let service;

        if (typeof options.service === "function") {
          service = await options.service(hook);
        } else {
          service = app.core_getService(options.service, hook.service.zone);
        } // Indicate we'd only like to count


        let query = {
          $limit: 0
        };

        if (typeof options.query === "function") {
          Object.assign(query, options.query(hook));
        } else {
          Object.assign(query, options.query);
        }

        count = service.find({
          query
        }).total;
      } else {
        count = await options.count(hook);
      }

      if (count > max) {
        throw new _errors.Forbidden("Resource quota exceeded (count limiting) on service " + options.service, {
          translation: {
            key: "COUNT_LIMITING"
          }
        });
      }
    }

    return hook;
  };
}