DapiDB
A peer-to-peer database for the decentralized web
DapiDB is a serverless, distributed, peer-to-peer database. DapiDB uses IPFS as its data storage and IPFS Pubsub to automatically sync databases with peers. It's an eventually consistent database that uses CRDTs for conflict-free database merges making DapiDB an excellent choice for decentralized apps (dApps), blockchain applications and offline-first web applications.
Data in DapiDB can be stored in a
- Key-Value Store
- Log Database (append-only log)
- Feed (same as log database but entries can be removed)
- Document Store (store indexed JSON documents)
- Counters
This is the Javascript implementation and it works both in Node.js and Browsers.
To get started, try the DapiDB CLI, read the Getting Started Guide or check Live demo 1, Live demo 2 or P2P TodoMVC app!
Table of Contents
Usage
Read the GETTING STARTED guide for a more in-depth tutorial and to understand how DapiDB works.
DapiDB currently supports Linux and OS X, Windows is not supported yet.
CLI
For the CLI tool to manage orbit-db database, see DapiDB CLI.
It can be installed from Npm with:
npm install orbit-db-cli -g
As a library
Install dependencies:
npm install orbit-db ipfs
Use it as a module:
const IPFS = require('ipfs')
const DapiDB = require('orbit-db')
// DapiDB uses Pubsub which is an experimental feature
// and need to be turned on manually.
// Note that these options need to be passed to IPFS in
// all examples even if not specfied so.
const ipfsOptions = {
EXPERIMENTAL: {
pubsub: true
},
}
// Create IPFS instance
const ipfs = new IPFS(ipfsOptions)
ipfs.on('error', (e) => console.error(e))
ipfs.on('ready', async () => {
// Create a database
const dapidb = new DapiDB(ipfs)
const db = await dapidb.log('database name')
// Add an entry to the database
const hash = await db.add('hello world')
// Get last 5 entries
const latest = db.iterator({ limit: 5 }).collect()
console.log(JSON.stringify(latest, null, 2))
})For more details, see examples for kvstore, eventlog, feed, docstore and counter.
The minimum required version of Node.js is now 8.0.0. To use with older versions of Node.js, we provide an ES5-compatible build through the npm package, located in dist/es5/ when installed through npm.
API
See API documentation for the full documentation.
Examples
Install dependencies
git clone https://github.com/dashevo/dapi-db.git
cd orbit-db
npm install
You'll also need babel and webpack, if you don't have them installed already:
npm install --global babel-cli
npm install --global webpack
Some dependencies depend on native addon modules, so you'll also need to meet node-gyp's installation prerequisites. Therefore, Linux users may need to
make clean && make
to redo the local package-lock.json with working native dependencies.
Browser example
In macOS:
npm run build
npm run examples:browser-macos
In Linux:
npm run build
npm run examples:browser-linux
Check the code in examples/browser/browser.html and try the live example.
Node.js example
npm run examples:node
Eventlog
See the code in examples/eventlog.js and run it with:
node examples/eventlog.js
More examples at examples.
Custom Store Types
You can add custom store types to DapiDB:
// define custom store type
class CustomStore extends DocumentStore {
constructor (ipfs, id, dbname, options) {
super(ipfs, id, dbname, options)
this._type = CustomStore.type
}
static get type () {
return 'custom'
}
}
// add custom type to dapidb
DapiDB.addDatabaseType(CustomStore.type, CustomStore)
// instantiate custom store
let dapidb = new DapiDB(ipfs, dbPath)
let store = dapidb.create(name, CustomStore.type)Development
Run Tests
npm test
Build
npm run build
Benchmark
node benchmarks/benchmark-add.js
See benchmarks/ for more benchmarks.
Logging
To enable DapiDB's logging output, set a global ENV variable called LOG to debug,warn or error:
LOG=debug node <file>
Background
Uses the following modules:
- ipfs-log
- crdts
- dapi-db-cache
- dapi-db-store
- dapi-db-eventstore
- dapi-db-feedstore
- dapi-db-kvstore
- dapi-db-docstore
- dapi-db-counterstore
- orbit-db-pubsub
- orbit-db-keystore
- ipfs
- ipfs-pubub-room
To understand a little bit about the architecture, check out a visualization of the data flow at https://github.com/haadcode/proto2 or a live demo: http://celebdil.benet.ai:8080/ipfs/Qmezm7g8mBpWyuPk6D84CNcfLKJwU6mpXuEN5GJZNkX3XK/.
License
MIT