https://github.com/hychen/flutter_js_datascript

Using DataScript in Flutter Apps.
https://github.com/hychen/flutter_js_datascript

datascript flutter

Last synced: 27 days ago
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Using DataScript in Flutter Apps.

• Host: GitHub
• URL: https://github.com/hychen/flutter_js_datascript
• Owner: hychen
• License: other
• Created: 2021-11-08T11:08:25.000Z (about 3 years ago)
• Default Branch: main
• Last Pushed: 2021-12-06T00:09:24.000Z (about 3 years ago)
• Last Synced: 2024-11-08T08:48:45.532Z (3 months ago)
• Topics: datascript, flutter
• Language: Dart
• Homepage:
• Size: 327 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • Changelog: CHANGELOG.md
  • License: LICENSE

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README

        


Using DataScript in Flutter Apps.

> This package is in very early stage and only be tested on MacOS. Use it with caution and file

any potential issues you see.

## Features

Use this package to

- Transact with Datoms.

- Query result by using [datalog](https://en.wikipedia.org/wiki/Datalog) language.

### Supported APIs:

  - creteConn

  - q

  - listen

  - unlisten

  - initDb

  - datoms

  - pull

  - pullMany

  - connFromDb

  - connFromDatoms

  - resetConn

  - initDb

  - dbWith

  - emptyDb

  - entityDb

  - entity

  - touch

  - resolveTempids

## Getting started

```shell

flutter pub add flutter_js_datascript

```

## Usage

```dart

import 'package:flutter_js_datascript/flutter_js_datascript.dart';

void main() async {

    var d = Datascript();

    // create DB schema, a regular JS Object

    final builder = SchemaBuilder()

      ..attr('aka', cardinality: Cardinality.many)

      ..attr('friend', valueType: ValueType.ref);

    final schema = builder.build();

    // Use JS API to create connection and add data to DB

    // create connection using schema

    var conn = d.createConn(schema: schema);

    // setup listener called main

    // pushes each entity (report) to an Array of reports

    // This is just a simple example. Make your own!

    var reports = [];

    d.listen(conn, 'main', (report) {

      reports.add(report);

    });

    // define initial datoms to be used in transaction

    var datoms = [

      {

        ":db/id": -1,

        "name": "Ivan",

        "age": 18,

        "aka": ["X", "Y"]

      },

      {

        ":db/id": -2,

        "name": "Igor",

        "aka": ["Grigory", "Egor"]

      },

      // use :db/add to link datom -2 as friend of datom -1

      [":db/add", -1, "friend", -2]

    ];

    // Tx is Js Array of Object or Array

    // pass datoms as transaction data

    var report = d.transact(conn, datoms, txMeta: "initial info about Igor and Ivan");

    var db = d.db(conn);

    // Fetch names of people who are friends with someone 18 years old

    // query values from conn with JS API

    var result = await d.q(

        '[:find ?n :in \$ ?a :where [?e "friend" ?f] [?e "age" ?a] [?f "name" ?n]]',

        [db, 18]);

    // print query result to console!

    print(result);  // [["Igor"]]

}

```