asksuite-core/services/RasaLayersRedisService.js

const md5 = require('md5');
const { CacheRedis } = require('../util/CacheRedis');
const AsksuiteUtil = require('../asksuite.util')();

class RasaLayersRedisService {
  constructor(config) {
    this.config = config;
    this.client = config.redis;
    this.caches = {};

    if (this.client && config.config && config.rasaLayers) {
      config.config.rasaLayers.languages &&
        config.config.rasaLayers.languages.forEach((lang) => {
          this.caches[lang] = new CacheRedis({
            client: this.client,
            prefixKey: `rasalayers:${lang}`,
            expirationTime: config.config.rasaLayers.expiration,
            isJson: true,
          });
        });
    }
  }

  async resolveText(text, language, order, languages) {
    const lang = AsksuiteUtil.resolveLanguage(language, languages);
    if (!text || !order || !order.length || !language || !this.caches[lang]) {
      return null;
    }

    const key = md5(this.normalizeText(text));
    const cached = await this.caches[lang].get(key);

    if (cached && cached.matches && cached.matches.length) {
      for (let i = 1; i <= order.length; i++) {
        const match = cached.matches.find(
          (e) => JSON.stringify(e.order) === JSON.stringify(order.slice(0, i)),
        );
        if (match) {
          return match.intent;
        }
      }
    }

    return null;
  }

  async saveToCache(intent, text, language, order, languages) {
    const lang = AsksuiteUtil.resolveLanguage(language, languages);
    if (!this.caches[lang]) {
      return;
    }

    const key = md5(this.normalizeText(text));
    let cached = await this.caches[lang].get(key);

    if (!cached) {
      cached = new CacheItem();
      cached.text = text;
    }

    if (order && order.length) {
      const orderStr = JSON.stringify(order);
      if (!cached.matches.find((e) => JSON.stringify(e.order) === orderStr)) {
        cached.matches.push({
          order,
          intent,
        });
      }
      await this.caches[lang].set(key, cached);
    }
  }

  normalizeText(text) {
    try {
      return text
        .trim()
        .replace(/\s\s+/g, ' ')
        .replace(/[.,\/#!$%^&*;:{}=\-_`~()?@]/g, '')
        .normalize('NFD')
        .replace(/[\u0300-\u036f]/g, '')
        .toLowerCase();
    } catch (e) {
      console.error('RedisService.normalizeText', text, e);
      return text;
    }
  }
}

class CacheItem {
  constructor() {
    this.text = '';
    this.matches = [];
  }
}

module.exports = RasaLayersRedisService;