itemsjs/src/fulltext.js

Created to perform fast search on small json dataset (up to 1000 elements).

const _ = require('./../vendor/lodash');
const lunr = require('lunr');

/**
 * responsible for making full text searching on items
 * config provide only searchableFields
 */
const Fulltext = function(items, config) {

  config = config || {};
  config.searchableFields = config.searchableFields || [];
  this.items = items;
  // creating index
  this.idx = lunr(function () {
    // currently schema hardcoded
    this.field('name', { boost: 10 });

    const self = this;
    _.forEach(config.searchableFields, function(field) {
      self.field(field);
    });
    this.ref('_id');

    /**
     * Remove the stemmer and stopWordFilter from the pipeline
     * stemmer: https://github.com/olivernn/lunr.js/issues/328
     * stopWordFilter: https://github.com/olivernn/lunr.js/issues/233
     */
    if (config.isExactSearch) {
      this.pipeline.remove(lunr.stemmer);
      this.pipeline.remove(lunr.stopWordFilter);
    }
  });

  let i = 1;

  _.map(items, (item) => {
    item._id = i;
    ++i;

    this.idx.add(item);
  });

  this.store = _.mapKeys(items, (doc) => {
    return doc._id;
  });
};

Fulltext.prototype = {

  search_full: function(query, filter) {
    return this.search(query, filter).map(v => {
      return this.store[v];
    });
  },

  search: function(query, filter) {
    if (!query && !filter) {
      return this.items ? this.items.map(v => v._id) : [];
    }

    let items;

    if (query) {
      items = _.map(this.idx.search(query), (val) => {
        const item = this.store[val.ref];
        return item;
      });
    }

    if (filter instanceof Function) {
      items = (items || this.items).filter(filter);
    }

    return items.map(v => v._id);
  }
};

module.exports = Fulltext;