mfsearch/mfsearch.js

Indexed search for MasterFormat-style datasets

const _ = require('lodash');
const {
  Search, SimpleTokenizer,
  StemmingTokenizer,
  UnorderedSearchIndex,
} = require('js-search');
const { stemmer } = require('porter-stemmer');

class MFSearch {
  //
  // by default, exclude all of divisions 40-46, 34, and 35
  constructor({ mfData, subsetRE = /^(?!(34|35|4[0123456]))/ }) {
    this.searchData = _.map(_.filter(mfData, (item) => {
      return item.code.match(subsetRE);
    }), (item, idx) => {
      return {
        code: item.code,
        level: item.level,
        description: item.description,
        primaryText: `${item.code} ${item.description}`,
        key: idx,
      };
    });
    const { stemmer } = require('porter-stemmer');
    this.search = new Search('description');
    this.search.tokenizer = new StemmingTokenizer(stemmer, new SimpleTokenizer());
    this.search.searchIndex = new UnorderedSearchIndex();
    this.search.addIndex('description');
    this.search.addIndex('code');
    this.search.addDocuments(this.searchData);
  }

  //
  // Full scan of search dataset
  locate ({ filterText = undefined, codePrefix = undefined, level = undefined }) {
    let ret;
    if (_.isUndefined(filterText)) {
      ret = this.searchData;
    } else {
      ret = this.search.search(filterText);
    }
    if (!_.isUndefined(level)) {
      ret = _.filter(ret, (item) => { return item.level == level; });
    }
    if (!_.isUndefined(codePrefix)) {
      ret = _.filter(ret, (item) => { return _.startsWith(item.code, codePrefix); });
    }
    return ret;
  };

  //
  // Return division (Level 1) items, optionally filtered.
  divisions ({ filterText = undefined }) {
    return this.locate({ filterText, level: 1 });
  }

  //
  // Return group (Level 2) items within specified division, optionally filtered.
  groupsOfDivision ({ filterText = undefined, divisionCode = '' }) {
    return this.locate({ filterText, codePrefix: divisionCode.substring(0,2), level: 2});
  }

  //
  // Return Level 3 items within specified division, optionally filtered.
  lineItemsOfGroup ({ filterText = undefined, groupCode = '' }) {
    return this.locate({ filterText, codePrefix: groupCode.substring(0,3), level: 3 });
  }

}

const codeStem = ({ code, level=1 }) => {
  const stemLength = level+1;
  if (level<1 || level>3 || code.length < stemLength ) return code;
  return code.substring(0,stemLength);
};
module.exports = { MFSearch, codeStem };