The offline-first database for your next application.
What is RxDB?
RxDB is a Javascript-based database with..
..these features.. | | ..for these plattforms |
- Reactive (rxjs)
- Replication / Sync
- Schemas (jsonschema)
- Mango-Query (MongoDB)
- Encryption
- Level-Adapters
- Import/Export (.json)
- MultiWindow-Support
- Leader-Election
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<img src="docs/files/icons/chrome.png" width="20px" />
<img src="docs/files/icons/firefox2.png" width="24px" />
browsers
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<img src="docs/files/icons/nodejs.png" width="30px" />
nodeJS
<br /><br />
<img src="docs/files/icons/angular.png" width="24px" />
angular/ng2
<br /><br />
<img src="docs/files/icons/react.png" width="24px" />
react
<br /><br />
<img src="docs/files/icons/ionic.ico" width="24px" />
ionic <br /><br />
<img src="docs/files/icons/cordova.png" width="24px" />
cordova / phonegap
<br /><br />
<img src="docs/files/icons/nativescript.png" width="24px" />
nativescript
<br /><br />
<img src="docs/files/icons/electron.png" width="24px" />
electron
<br />
</td>
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Quickstart
Installation:
npm install rxdb --save
ES6:
import * as RxDB from 'rxdb';
RxDB.create('heroesDB', 'websql', 'myLongAndStupidPassword', true)
.then(db => db.collection('mycollection', mySchema))
.then(collection => collection.insert({name: 'Bob'}))
ES5:
var RxDB = require('rxdb');
RxDB.create('heroesDB', 'websql', 'myLongAndStupidPassword', true)
.then(function(db) {return db.collection('mycollection', mySchema);})
.then(function(collection) {collection.insert({name: 'Bob'});})
Features
Mango-Query
To find data in your collection, you can use chained mango-queries, which you maybe know from mongoDB or mongoose. Example:
myCollection
.find()
.where('name').ne('Alice')
.where('age').gt(18).lt(67)
.limit(10)
.sort('-age')
.exec().then( docs => {
console.dir(docs);
});
Reactive
RxDB implements rxjs to make your data reactive.
This makes it easy to always show the real-time database-state in the dom without manually re-submitting your queries.
heroCollection
.find()
.sort('name')
.$
.subscribe( docs => {
myDomElement.innerHTML = docs
.map(doc => '<li>' + doc.get('name') + '</li>')
.join();
});
MultiWindow/Tab - Support
When two instances of RxDB use the same storage-engine, their state and action-stream will be broadcasted.
This means with two browser-windows the change of window #1 will automatically affect window #2. This works completely serverless.
Replication
Because RxDB relies on glorious PouchDB, it is easy to replicate
the data between devices and servers. And yes, the changeEvents are also synced.
Schema
Schemas are defined via jsonschema and are used to describe your data. Beside the jsonschema-keywords, you can also use primary and encrypted. Example:
var mySchema = {
title: "hero schema",
description: "describes a simple hero",
type: "object",
properties: {
name: {
type: "string",
primary: true
},
secret: {
type: "string",
encrypted: true
},
skills: {
type: "array",
maxItems: 5,
uniqueItems: true,
item: {
type: "object",
properties: {
name: {
type: "string"
},
damage: {
type: "number"
}
}
}
}
},
required: ["color"]
};
Encryption
By setting a schema-field to encrypted: true
, the value of this field will be stored in encryption-mode and can't be read without the password. Of course you can also encrypt nested objects. Example:
"secret": {
"type": "string",
"encrypted": true
}
Level-adapters
The underlaying pouchdb can use different adapters as storage engine. You can so use RxDB in different environments by just switching the adapter.
For example you can use websql in the browser, localstorage in mobile-browsers and a leveldown-adapter in nodejs.
RxDB.plugin(require('rxdb-adapter-localstorage'));
RxDB.create('heroesDB', 'localstorage');
Import / Export
RxDB lets you import and export the whole database or single collections into json-objects. This is helpful to trace bugs in your application or to move to a given state in your tests.
```js
// export a single collection
myCollection.dump()
.then(json => {
console.dir(json);
});
// export the whole database
myDatabase.dump()
.then(json => {
console.dir(json);
});
// import the dump to the collection
emptyCollection.importDump(json)
.then(() => {
console.log('done');
});
// import the dump to the database
emptyDatabase.importDump(json)
.then(() => {
console.log('done');
});
<h3>Leader-Election</h3>
<p>
Imagine your website needs to get a piece of data from the server once every minute. To accomplish this task
you create a websocket or pull-intervall. If your user now opens the site in 5 tabs parallel, it will run the intervall
or create the socket 5 times. This is a waste of ressources which can be solved by RxDB's LeaderElection.
</p>
```js
myRxDatabase.waitForLeadership()
.then(() => {
// this will only run when the instance becomes leader.
mySocket = createWebSocket();
});
In this example the leader is marked with the crown ♛
Getting started
Get started now by reading the docs or exploring the example-projects.
Contribute
[Check out how you can contribute to this project](./docs/Contribute.md).