README.md

Notice: this library isn't maintained anymore

JayData is a unified data access library for JavaScript to CRUD data from different sources like WebSQL/SQLite, IndexedDB, MongoDb, OData, HTML5 localStorage. The library can be integrated with React, Angular2, Durandal, KendoUI, Knockout.js, Handlebars.js or Sencha Touch 2 and can be used on Node.js as well. Check out the latest JayData examples

JayData not only provides JavaScript Language Query (JSLQ) syntax to access local (in-browser and mobile) and remote databases, but builds the queries and executes/processes the requests of the essential data sources and data services to make developers able to concentrate only on the business logic.

Microsoft .NET developers can utilize Entity Framework and LINQ on server-side to perform operations on data from different databases. The aim of JayData library is to give a similar tool to JavaScript developers.

JayData is cross-platform (runs on HTML5 desktop and mobile browsers, can be hosted in Cordova/PhoneGap environment on iPhone, iPad, Android or Windows Phone 8+) and cross-layer as it works on client-side and server-side (Node.JS).

Please read the release notes for current status of the providers.

Visit http://jaydata.org for detailed information and documentation.

Official builds are released on CodePlex (http://jaydata.codeplex.com) can be used to develop applications, to get the structured sourcecode to develop JayData itself, visit http://github.com/jaystack/jaydata

Feed of Latest releases, tutorials: https://twitter.com/jaydataorg Feed of commits in development branch: https://twitter.com/jaydatadev

JayData comes with multiple licensing: you can use it under MIT license if ship software software under MIT, but it should be used under GPL if you distribute your software under GPLv2. JayData Pro is a closed-source commercial product recommended for enterprise projects and commercial development efforts. http://jaystack.com/licensing

Installation

$ npm install jaydata

How to build

$ git clone https://github.com/jaystack/jaydata.git
$ cd jaydata
$ npm install
$ gulp

Use JayData as a standalone global library

<script  type="text/javascript" src="jaydata.min.js"></script>

Providers are lazy loaded from the same location as the core JayData script under the jaydataproviders folder. If you want to use a JayData module, include it manually in a <script> tag.

Use Jaydata with System.js

Using JayData with System.js needs a little bit of a setup and you have to map all providers you want to use in your application.

var map = {
    'jaydata/core': 'lib/jaydata/jaydata.min',
    'jaydata/odata': 'lib/jaydata/jaydataproviders/oDataProvider.min'
};

var meta = {
    'jaydata/odata': {
        format: 'cjs',
        deps: ['jaydata/core']
    }
};

var config = {
    map: map,
    meta: meta
};

System.config(config);

With this setup you can now import the jaydata/odata module in your application code. See a full example in Angular2 here.

Use JayData with Require.js

If you want to use Require.js to import JayData into your application, you need to set the path configuration correctly:

requirejs.config({
    paths: {
        'jaydata/core': '../lib/jaydata/jaydata.min',
        'jaydata/odata': '../lib/jaydata/jaydataproviders/oDataProvider.min',
    }
});

See a working example using Require.js and Durandal here.

JayData basics in 7 simple steps

In most scenarios, the 7 simple steps of JayData basics are enough to handle data of your application. For more details, visit http://jaydata.org.

Step 1 - Define your data model

Simple model that works online and offline as well. Define your data model:

var Todo = $data.Entity.extend("Todo", {
    Id: { type: "int", key: true, computed: true },
    Task: { type: String, required: true, maxLength: 200 },
    DueDate: { type: Date },
    Completed: { type: Boolean }
});

var TodoDatabase = $data.EntityContext.extend("TodoDatabase", {
    Todos: { type: $data.EntitySet, elementType: "Todo" }
});

Step 2 - Initialize the data storage

OData

You can Initialize your context to handle an OData endpoint just by passing the OData service URL as a single string parameter.

var todoDB = new TodoDatabase("http://mysite.com/my.svc");

Local database

If you want to use a local database, pass the name of your database as a string. JayData automatically detects what type of local database solution is available on the client and creates a context to an IndexedDB, WebSQL, LocalStorage or InMemory database.

var todoDB = new TodoDatabase("MyTodoDatase");

WebSQL

You can even specify, what type of database you want to use by providing a storage provider configuration object.

var todoDB = new TodoDatabase({ 
    provider: 'webSql', databaseName: 'MyTodoDatabase' 
});

Step 3 - Create data

You can create new data by adding new entities to an entity set.

Simple

You can add a single entity to an entity set...

todoDB.onReady(function(){
    var task = todoDB.Todos.add({ Task: 'Step0: Get this list', Completed: true });
    todoDB.saveChanges(function(){
        alert(task.Id);
    });
});

Batch

...or you can create multiple new entities by using the addMany function. In the handler of the saveChanges function you will get how many entities were saved.

todoDB.onReady(function(){
    var tasks = todoDB.Todos.addMany([
        { Task: 'Step1: Define your data model'},
        { Task: 'Step2: Initialize the data storage'},
        { Task: 'Step3: Create data' }
    ]);
    todoDB.saveChanges(function(count){
        alert("Created " + count + " new task");
        tasks.forEach(function(todo){ alert(todo.Id); });
    });
});

Step 4 - Read data

All items

To retrieve all database items as an array, use the toArray function.

todoDB.onReady(function(){
    todoDB.Todos.toArray(function(todos){
        yourTemplate.render(todos);
    });
});

Filter #1

You can filter your data just like the native filter function of JavaScript. If you want to handle your result in a loop use the forEach function.

todoDB.onReady(function(){
    todoDB.Todos
        .filter(function(todo){
            return todo.Completed == true || todo.Task.startsWith("Step2");
        })
        .forEach(function(todo){
            yourTemplate.render(todo);
        });
});

Using forEach is equivalent to this:

todoDB.onReady(function(){
    todoDB.Todos
        .filter(function(todo){
            return todo.Completed == true || todo.Task.startsWith("Step2");
        })
        .toArray(function(todos){
            todos.forEach(function(todo){
                yourTemplate.render(todo);
            });
        });
});

Filter #2

You can pass a query parameters object as the second argument of the filter function and access these query parameters on this in the query function.

todoDB.onReady(function(){
    todoDB.Todos
        .filter(function(todo){
            return todo.Completed == true || todo.Task.startsWith(this.stepName);
        }, {
            stepName: 'Step2'
        })
        .forEach(function(todo){
            yourTemplate.render(todo); 
        });
});

Filter #3

Instead of a JavaScript function you can use a query string in the filter function. This is specially useful, when you want to create your query dynamically.

todoDB.onReady(function(){
    var stepName = 'Step2';
    todoDB.Todos
        .filter("it.Completed || it.task.startsWith('" + stepName + "')")
        .forEach(function(todo){
            yourTemplate.render(todo); 
        });
});

Mapping

In some scenarios you want to just retrieve some fields of your entity and map these fields as different names.

todoDB.onReady(function(){
    todoDB.Todos
        .map(function(todo){
            return {
                _task: todo.Task,
                _completed: todo.Completed
            }
        })
        .toArray(function(todos){
            yourTemplate.render(todos);
        });
});

Paging

As you store more and more entities in your database, it's practical to retrieve only a subset of your data by using paging functions.

todoDB.onReady(function(){
    todoDB.Todos
        .skip(2)
        .take(3)
        .toArray(function(todo){
            yourTemplate.render(todo);
        });
});

Ordering

If you want to sort your result by a selected field, use orderBy or orderByDescending. As you can still use a string instead of a function in the query function, you can dynamically construct your ordering query.

todoDB.onReady(function(){
    todoDB.Todos
        .orderBy("it.Task")
        .toArray(function(todo){
            yourTemplate.render(todo);
        });
});

If you want more dynamic control over order direction, use the order function. If you need descending ordering on the field, use the - sign before the field name.

todoDB.onReady(function(){
    todoDB.Todos
        .order("-it.Task")
        .toArray(function(todo){
            yourTemplate.render(todo);
        });
});

Step 5 - Update data

To update an entity, attach it to the context and JayData will track the changes on the entity. On calling the saveChanges function, your attached and updated entities will be saved.

todoDB.onReady(function(){
    todoDB.Todos.single("it.Id == 1", function(todo){
        todoDB.attach(todo);
        todo.Completed = true;
        todoDB.saveChanges(function(count){
            alert("Updated " + count + " task");
        });
    });
});

Step 6 - Delete data

Simple

Just like updating data, but instead of attach you will use remove.

todoDB.onReady(function(){
    todoDB.Todos.single("it.Id == 3", function(todo){
        todoDB.Todos.remove(todo);
        todoDB.saveChanges(function(count){
            alert("Removed " + count + " task");
        });
    });
});

Batch

Use the removeAll function if you want to truncate all data in a single entity set.

todoDB.onReady(function(){
    todoDB.Todos.removeAll(function(){
        alert("Removed all tasks");
    });
});

Step 7 - Generate some UI with jQuery

todoDB.onReady(function(){
    todoDB.Todos
        .forEach(function(todo) {
            $('#todos')
                .append('<li><b>' + todo.Task + '</b>' + (todo.Completed ? ' - completed' : '') + '</li>');
        });
});

Related projects

JaySvcUtil - Code generator tool that builds JayData data model classes from $metadata service of OData endpoints.