json_text_search 0.0.1-beta.1

A Dart full-text search (FTS) library that allows creation of inverted indexes on JSON collections and FTS querying of the same index.

example/json_text_search_example.dart

/// In your code file add the following import:
import 'package:json_text_search/json_text_search.dart';

/// This simple example creates an index on the [sampleNews] dataset below and
/// then finds the index entry for the term "intel".
void main() async {
  //

  // our index that only tokenizes the "hashTags", "name" and
  // "description" fields.
  final indexedFields = <String, int>{
    //

    // "hashTags" is the highest priority field and will return a relevance
    // five times as high as the "description" field
    'hashTags': 5,
    'name': 2,
    'description': 1
  };
  final indexer = JsonIndexBuilder.impl(indexedFields: indexedFields);

  // index the sampleNews on the "hashTags", "name" and "description" fields
  final index = await indexer.index(sampleNews);

  //  Find [IndexEntry] for the term "intel".
  final indexEntry = index['intel'];
  if (indexEntry != null) {
    //
    // print the references count for indexEntry
    print(
        'Found ${indexEntry.references.length} documents for the term "${indexEntry.term}"');

    // print the title and relevance for each reference in the indexEntry
    for (final reference in indexEntry.references.values) {
      print(
          '[Title: "${reference.document['name']}"] [relevance: ${reference.relevance.toStringAsFixed(3)}]');
    }
  }
}

/// A small sample dataset.
const sampleNews = {
  'ef3b0cb6-0297-502b-bd77-283246bc0014': {
    'avatarImageUrl':
        'https://firebasestorage.googleapis.com/v0/b/buysellhold-322d1.appspot.com/o/logos%2FJPM-C%3AXNYS.png?alt=media&token=deba8c6d-019e-4d49-9faa-d641a3cf1986',
    'description':
        'JPMorgan Sees ‘Stratospheric’ \$380 Oil on Worst-Case Russian Cut',
    'entityType': 'NewsItem',
    'hashTags': ['#JPMorganChase'],
    'id': 'ef3b0cb6-0297-502b-bd77-283246bc0014',
    'itemGuid': 'germany-risks-cascade-utility-failures-194853753.html',
    'linkUrl':
        'https://finance.yahoo.com/news/germany-risks-cascade-utility-failures-194853753.html',
    'locale': 'Locale.en_US',
    'name': 'Germany Risks a Cascade of Utility Failures Economy Chief Says',
    'publicationDate': '2022-07-02T19:48:53.000Z',
    'publisher': {
      'linkUrl': 'https://www.bloomberg.com/',
      'title': 'Bloomberg'
    },
    'timestamp': 1656802194091
  },
  'f1064cca-bf6d-5689-900b-ecb8769fe30b': {
    'avatarImageUrl':
        'https://firebasestorage.googleapis.com/v0/b/buysellhold-322d1.appspot.com/o/logos%2FINTC%3AXNGS.png?alt=media&token=cfefaa0a-7f06-42f8-a316-954ded1fd703',
    'description':
        'Under CEO Pat Gelsinger, Intel has committed to massively increasing its capital spending investments by tens of billions of dollars. But with a rapidly slowing global economy, repeated product delays, rising competitive threats, and political uncertainty, it might need more help to fund its ambitions. One good place to find it would be Intel (ticker: INTC) generous dividend payout. While the chip maker has paid a consistent dividend for three decades straight, it needs to do whatever it takes to shore up its future—up to and including cutting its dividend. Under CEO Pat Gelsinger, Intel has committed to massively increasing its capital spending investments by tens of billions of dollars.',
    'entityType': 'NewsItem',
    'hashTags': ['#Intel'],
    'id': 'f1064cca-bf6d-5689-900b-ecb8769fe30b',
    'itemGuid':
        'intel-stock-dividend-future-51656450364?siteid=yhoof2&yptr=yahoo',
    'linkUrl':
        'https://www.barrons.com/articles/intel-stock-dividend-future-51656450364?siteid=yhoof2&yptr=yahoo',
    'locale': 'Locale.en_US',
    'name':
        'Intel Should Slash Its Dividend The Chip Maker s Future May Depend on It',
    'publicationDate': '2022-06-29T12:00:00.000Z',
    'publisher': {'linkUrl': 'http://www.barrons.com/', 'title': 'Barrons com'},
    'timestamp': 1656540522708
  },
  'f83c0c39-8cc3-5b0e-91de-61e829ea65dc': {
    'avatarImageUrl':
        'https://firebasestorage.googleapis.com/v0/b/buysellhold-322d1.appspot.com/o/logos%2FXOM%3AXNYS.png?alt=media&token=c94499b0-5937-47ea-8f89-94d65d3ed065',
    'description':
        'Sell Exxon Mobil and other energy stocks before these headwinds hit prices once again: ',
    'entityType': 'NewsItem',
    'hashTags': ['#ExxonMobil'],
    'id': 'f83c0c39-8cc3-5b0e-91de-61e829ea65dc',
    'itemGuid':
        'sell-exxon-mobil-and-other-energy-stocks-before-these-headwinds-once-again-hit-prices-11656527286?siteid=yhoof2&yptr=yahoo',
    'linkUrl':
        'https://www.marketwatch.com/story/sell-exxon-mobil-and-other-energy-stocks-before-these-headwinds-once-again-hit-prices-11656527286?siteid=yhoof2&yptr=yahoo',
    'locale': 'Locale.en_US',
    'name':
        'Sell Exxon Mobil and other energy stocks before these headwinds hit prices once again',
    'publicationDate': '2022-06-29T18:28:00.000Z',
    'publisher': {
      'linkUrl': 'http://www.marketwatch.com/',
      'title': 'MarketWatch'
    },
    'timestamp': 1656630576652
  }
};