458 lines
11 KiB
Markdown
458 lines
11 KiB
Markdown
|
|
What is embark
|
|
======
|
|
|
|
[](https://gitter.im/iurimatias/embark-framework?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
|
|
|
|
Embark is a framework that allows you to easily develop and deploy DApps.
|
|
|
|
With Embark you can:
|
|
* Automatically deploy contracts and make them available in your JS code. Embark watches for changes, and if you update a contract, Embark will automatically redeploy the contracts (if needed) and the dapp.
|
|
* Use any build pipeline or tool you wish, including grunt and meteor. (for 1.x, plugins coming soon for 2.x series)
|
|
* Do Test Driven Development with Contracts using Javascript.
|
|
* Easily deploy to & use decentralized systems such as IPFS.
|
|
* Keep track of deployed contracts, deploy only when truly needed.
|
|
* Manage different chains (e.g testnet, private net, livenet)
|
|
* Quickly create advanced DApps using multiple contracts that can interact with decentralized infrastructure for storage and comunication.
|
|
|
|
Table of Contents
|
|
======
|
|
* [Installation](#installation)
|
|
* [Usage Demo](#usage---demo)
|
|
* [Dashboard](#dashboard)
|
|
* [Creating a new DApp](#creating-a-new-dapp)
|
|
* [Using and Configuring Contracts](#dapp-structure)
|
|
* [EmbarkJS](#embarkjs)
|
|
* [EmbarkJS - Storage (IPFS)](#embarkjs---storage)
|
|
* [EmbarkJS - Communication (Whisper)](#embarkjs---communication)
|
|
|
|
Installation
|
|
======
|
|
Requirements: geth (1.4.4 or higher), node (5.0.0) and npm
|
|
Optional: serpent (develop) if using contracts with Serpent, testrpc or ethersim if using the simulator or the test functionality.
|
|
Further: depending on the dapp stack you choose: [IPFS](https://ipfs.io/)
|
|
|
|
```Bash
|
|
$ npm -g install embark
|
|
|
|
# If you plan to use the simulator instead of a real ethereum node.
|
|
$ npm -g install testrpc
|
|
```
|
|
|
|
See [Complete Installation Instructions](https://github.com/iurimatias/embark-framework/wiki/Installation).
|
|
|
|
Usage - Demo
|
|
======
|
|
You can easily create a sample working DApp with the following:
|
|
|
|
```Bash
|
|
$ embark demo
|
|
$ cd embark_demo
|
|
```
|
|
|
|
To run a ethereum rpc simulator simply run:
|
|
|
|
```Bash
|
|
$ embark simulator
|
|
```
|
|
|
|
Or Alternatively, you can run a REAL ethereum node for development purposes:
|
|
|
|
```Bash
|
|
$ embark blockchain
|
|
```
|
|
|
|
By default embark blockchain will mine a minimum amount of ether and will only mine when new transactions come in. This is quite usefull to keep a low CPU. The option can be configured at config/blockchain.json
|
|
|
|
Then, in another command line:
|
|
|
|
```Bash
|
|
$ embark run
|
|
```
|
|
This will automatically deploy the contracts, update their JS bindings and deploy your DApp to a local server at http://localhost:8000
|
|
|
|
Note that if you update your code it will automatically be re-deployed, contracts included. There is no need to restart embark, refreshing the page on the browser will do.
|
|
|
|
Dashboard
|
|
=====
|
|
|
|
Embark 2 comes with a terminal dashboard.
|
|
|
|
|
|
|
|
The dashboard will tell you the state of your contracts, the enviroment you are using, and what embark is doing at the moment.
|
|
|
|
**available services**
|
|
|
|
Available Services will display the services available to your dapp in green, if one of these is down then it will be displayed in red.
|
|
|
|
**logs and console**
|
|
|
|
There is a console at the bottom which can be used to interact with contracts or with embark itself. type ```help``` to see a list of available commands, more commands will be added with each version of Embark.
|
|
|
|
Creating a new DApp
|
|
======
|
|
|
|
If you want to create a blank new app.
|
|
|
|
```Bash
|
|
$ embark new AppName
|
|
$ cd AppName
|
|
```
|
|
|
|
DApp Structure
|
|
======
|
|
|
|
```Bash
|
|
app/
|
|
|___ contracts/ #solidity or serpent contracts
|
|
|___ html/
|
|
|___ css/
|
|
|___ js/
|
|
config/
|
|
|___ blockchain.json #environments configuration
|
|
|___ contracts.json #contracts configuration
|
|
test/
|
|
|___ #contracts tests
|
|
```
|
|
|
|
Solidity/Serpent files in the contracts directory will automatically be deployed with embark run. Changes in any files will automatically be reflected in app, changes to contracts will result in a redeployment and update of their JS Bindings
|
|
|
|
Using Contracts
|
|
======
|
|
Embark will automatically take care of deployment for you and set all needed JS bindings. For example, the contract below:
|
|
|
|
```Javascript
|
|
# app/contracts/simple_storage.sol
|
|
contract SimpleStorage {
|
|
uint public storedData;
|
|
|
|
function SimpleStorage(uint initialValue) {
|
|
storedData = initialValue;
|
|
}
|
|
|
|
function set(uint x) {
|
|
storedData = x;
|
|
}
|
|
function get() constant returns (uint retVal) {
|
|
return storedData;
|
|
}
|
|
}
|
|
```
|
|
Will automatically be available in Javascript as:
|
|
|
|
```Javascript
|
|
# app/js/index.js
|
|
SimpleStorage.set(100);
|
|
SimpleStorage.get();
|
|
SimpleStorage.storedData();
|
|
```
|
|
|
|
You can specify for each contract and environment its gas costs and arguments:
|
|
|
|
```Json
|
|
# config/contracts.json
|
|
{
|
|
"development": {
|
|
"gas": "auto",
|
|
"contracts": {
|
|
"SimpleStorage": {
|
|
"args": [
|
|
100
|
|
]
|
|
}
|
|
}
|
|
}
|
|
}
|
|
```
|
|
|
|
If you are using multiple contracts, you can pass a reference to another contract as ```$ContractName```, Embark will automatically replace this with the correct address for the contract.
|
|
|
|
|
|
```Json
|
|
# config/contracts.json
|
|
{
|
|
...
|
|
"development": {
|
|
"contracts": {
|
|
"SimpleStorage": {
|
|
"args": [
|
|
100,
|
|
$MyStorage
|
|
]
|
|
},
|
|
"MyStorage": {
|
|
"args": [
|
|
"initial string"
|
|
]
|
|
},
|
|
"MyMainContract": {
|
|
"args": [
|
|
$SimpleStorage
|
|
]
|
|
}
|
|
}
|
|
}
|
|
...
|
|
}
|
|
```
|
|
|
|
You can now deploy many instances of the same contract. e.g
|
|
|
|
|
|
```Json
|
|
# config/contracts.json
|
|
{
|
|
"development": {
|
|
"contracts": {
|
|
"Currency": {
|
|
"deploy": false,
|
|
"args": [
|
|
100
|
|
]
|
|
},
|
|
"Usd": {
|
|
"instanceOf": "Currency",
|
|
"args": [
|
|
200
|
|
]
|
|
},
|
|
"MyCoin": {
|
|
"instanceOf": "Currency",
|
|
"args": [
|
|
200
|
|
]
|
|
}
|
|
}
|
|
}
|
|
}
|
|
...
|
|
```
|
|
|
|
Contracts addresses can be defined, If an address is defined the contract wouldn't be deployed but its defined address will be used instead.
|
|
|
|
|
|
```Json
|
|
# config/contracts.json
|
|
{
|
|
...
|
|
"development": {
|
|
"contracts": {
|
|
"UserStorage": {
|
|
"address": "0x123456"
|
|
},
|
|
"UserManagement": {
|
|
"args": [
|
|
"$UserStorage"
|
|
]
|
|
}
|
|
}
|
|
}
|
|
...
|
|
}
|
|
```
|
|
|
|
EmbarkJS
|
|
======
|
|
|
|
EmbarkJS is a javascript library meant to abstract and facilitate the development of DApps.
|
|
|
|
**promises**
|
|
|
|
methods in EmbarkJS contracts will be converted to promises.
|
|
|
|
```Javascript
|
|
var myContract = new EmbarkJS.Contract({abi: abiObject, address: "0x123"});
|
|
myContract.get().then(function(value) { console.log("value is " + value.toNumber) });
|
|
```
|
|
|
|
**deployment**
|
|
|
|
Client side deployment will be automatically available in Embark for existing contracts:
|
|
|
|
```Javascript
|
|
var myContract = new EmbarkJS.Contract({abi: abiObject, code: code});
|
|
myContract.deploy().then(function(address) {});
|
|
```
|
|
|
|
or it can be manually definied as
|
|
|
|
```Javascript
|
|
var myContract = new EmbarkJS.Contract({abi: abiObject, code: code});
|
|
myContract.deploy().then(function(address) {});
|
|
```
|
|
|
|
EmbarkJS - Storage
|
|
======
|
|
|
|
**initialization**
|
|
|
|
The current available storage is IPFS. it can be initialized as
|
|
|
|
```Javascript
|
|
EmbarkJS.Storage.setProvider('ipfs',{server: 'localhost', port: '5001'})
|
|
```
|
|
|
|
**Saving Text**
|
|
|
|
```Javascript
|
|
EmbarkJS.Storage.saveText("hello world").then(function(hash) {});
|
|
```
|
|
|
|
**Retrieving Data/Text**
|
|
|
|
```Javascript
|
|
EmbarkJS.Storage.get(hash).then(function(content) {});
|
|
```
|
|
|
|
**Uploading a file**
|
|
|
|
```HTML
|
|
<input type="file">
|
|
```
|
|
|
|
```Javascript
|
|
var input = $("input[type=file"]);
|
|
EmbarkJS.Storage.uploadFile(input).then(function(hash) {});
|
|
```
|
|
|
|
**Generate URL to file**
|
|
|
|
```Javascript
|
|
EmbarkJS.Storage.getUrl(hash);
|
|
```
|
|
|
|
EmbarkJS - Communication
|
|
======
|
|
|
|
**initialization**
|
|
|
|
The current available communication is Whisper.
|
|
|
|
**listening to messages**
|
|
|
|
```Javascript
|
|
EmbarkJS.Messages.listenTo({topic: ["achannel", "anotherchannel"]}).then(function(message) { console.log("received: " + message); })
|
|
```
|
|
|
|
**sending messages**
|
|
|
|
you can send plain text
|
|
|
|
```Javascript
|
|
EmbarkJS.Messages.sendMessage({topic: "achannel", data: 'hello world'})
|
|
```
|
|
|
|
or an object
|
|
|
|
```Javascript
|
|
EmbarkJS.Messages.sendMessage({topic: "achannel", data: {msg: 'hello world'}})
|
|
```
|
|
|
|
Tests
|
|
======
|
|
|
|
You can run specs with ```embark test```, it will run any test files under ```test/```.
|
|
|
|
Embark includes a testing lib to fastly run & test your contracts in a EVM.
|
|
|
|
```Javascript
|
|
# test/simple_storage_spec.js
|
|
|
|
var assert = require('assert');
|
|
var Embark = require('embark-framework');
|
|
var EmbarkSpec = Embark.initTests();
|
|
var web3 = EmbarkSpec.web3;
|
|
|
|
describe("SimpleStorage", function() {
|
|
before(function(done) {
|
|
var contractsConfig = {
|
|
"SimpleStorage": {
|
|
args: [100]
|
|
}
|
|
};
|
|
EmbarkSpec.deployAll(contractsConfig, done);
|
|
});
|
|
|
|
it("should set constructor value", function(done) {
|
|
SimpleStorage.storedData(function(err, result) {
|
|
assert.equal(result.toNumber(), 100);
|
|
done();
|
|
});
|
|
});
|
|
|
|
it("set storage value", function(done) {
|
|
SimpleStorage.set(150, function() {
|
|
SimpleStorage.get(function(err, result) {
|
|
assert.equal(result.toNumber(), 150);
|
|
done();
|
|
});
|
|
});
|
|
});
|
|
|
|
});
|
|
```
|
|
|
|
Embark uses [Mocha](http://mochajs.org/) by default, but you can use any testing framework you want.
|
|
|
|
Working with different chains
|
|
======
|
|
You can specify which environment to deploy to:
|
|
|
|
|
|
```$ embark blockchain production```
|
|
|
|
```$ embark run production```
|
|
|
|
The environment is a specific blockchain configuration that can be managed at config/blockchain.json
|
|
|
|
```Json
|
|
# config/blockchain.json
|
|
...
|
|
"livenet": {
|
|
"networkType": "livenet",
|
|
"rpcHost": "localhost",
|
|
"rpcPort": 8545,
|
|
"rpcCorsDomain": "http://localhost:8000",
|
|
"account": {
|
|
"password": "config/production/password"
|
|
}
|
|
},
|
|
...
|
|
```
|
|
|
|
Structuring Application
|
|
======
|
|
|
|
Embark is quite flexible and you can configure you're own directory structure using ```embark.json```
|
|
|
|
```Json
|
|
# embark.json
|
|
{
|
|
"contracts": ["app/contracts/**"],
|
|
"app": {
|
|
"css/app.css": ["app/css/**"],
|
|
"js/app.js": ["embark.js", "app/js/**"],
|
|
"index.html": "app/index.html"
|
|
},
|
|
"buildDir": "dist/",
|
|
"config": "config/"
|
|
}
|
|
```
|
|
|
|
Deploying to IPFS
|
|
======
|
|
|
|
To deploy a dapp to IPFS, all you need to do is run a local IPFS node and then run ```embark ipfs```.
|
|
If you want to deploy to the livenet then after configuring you account on ```config/blockchain.json``` on the ```production``` environment then you can deploy to that chain by specifying the environment ```embark ipfs production```.
|
|
|
|
LiveReload Plugin
|
|
======
|
|
|
|
Embark works quite well with the LiveReload Plugin
|
|
|
|
Donations
|
|
======
|
|
|
|
If you like Embark please consider donating to 0x8811FdF0F988f0CD1B7E9DE252ABfA5b18c1cDb1
|