Stellar Federation resolver for NodeJS
NodeJS implementation of the Stellar Federation protocol. Modular, framework-agnostic, with multi-database support.
Features
- Integrates with any web framework (Express, Sails, Koa, Hapi, etc).
- Minimalistic configuration.
- Flexible federation requests handling.
- Extendable via custom providers mechanism.
Installation
$ npm i stellar-federation-resolver-node
Configuration
Minimal configuration
const FederationResolver = require('stellar-federation-resolver-node')
const resolver = new FederationResolver({
domains: '*' // allow all domains
})
All configuration options
{
domains: 'foo.com,bar.net', // list of domains available for lookup
provider: myCustomResolver, // custom federation provider (optional)
resolveByName: nameResolver, // callback for name request resolution (optional)
resolveById: idResolver, // callback for id request resolution (optional)
resolveByForward: forwardResolver,// callback for forward request resolution (optional)
horizon: 'https://my.horizon' // URL of horizon server for txid lookups (optional)
}
In case if you don't specify the resolution callback for any request type, the resolver will return an error for that particular type.
Parameter horizon
is required only for txid
lookup. You can safely omit it if you don't plan to allow txid
requests.
Usage
Assume we have database with table User and some basic set of parameters.
{
"id": 83475301,
"name": "Tunde",
"lastName": "Adebayo",
"userNicname": "tunde_adebayo",
"domain": "foo.com",
"stellarAccount": "GAIGZHHWK3REZQPLQX5DNUN4A32CSEONTU6CMDBO7GDWLPSXZDSYA4BK"
}
Resolution
Resolution callbacks can be defined using one of the following signatures:
With callback function (Sequelize ORM is used here):
resolveByName: (searchParams, cb) => {
User.findOne({
where: {
userNicname: searchParams.query,
domain: searchParams.domain
}
})
.catch(err => cb(err))
.then(user => cb(null, {
username: user.userNicname,
accountId: user.stellarAccount
}))
}
With promise (on the example of Mongoose ORM):
resolveByName: (searchParams) => {
return User.findOne({
userNicname: searchParams.query,
domain: searchParams.domain
})
.exec()
.then(user => {
username: user.userNicname,
accountId: user.stellarAccount
})
}
Resolver callbacks expect to receive an object with standard set of fields:
{
username: 'username', // unique username
domain: 'foo.com', // domain used for resolution
memo: '4523452345', // (optional) data you want associate with user
memoType: 'text', // (optional) data type, one of ['text', 'id', 'hash']
}
The "memo" field can be used to track third-party system transactions.
resolveById: (searchParams) => {
return User.findOne({
where: {
stellarAccount: searchParams.query,
domain: searchParams.domain
}
})
.then(user => {
username: user.userNicname,
accountId: user.stellarAccount,
memoType: 'text',
memo: user.id
})
}
ExpressJS example
var express = require('express')
// create and configure the express instance
var app = express()
...
var FederationResolver = require('stellar-federation-resolver-node')
//create federation resolver
var resolver = new FederationResolver({
domains: 'my.domain.com',
resolveByName: (searchParams) => {
//your implementation here
}
resolveById: (searchParams) => {
//your implementation here
}
})
//and use it along with middleware
app.get('/federation', (req, res, next) => {
//allow cross-domain requests
res.header("Access-Control-Allow-Origin", "*")
//pass query params to resolver
resolver.resolve(req.query)
//errors are handled by the global error handler
.catch(err => next(err))
//and return JSON if everything ok
.then(record => res.json(record))
})
// error handler
app.use((err, req, res, next) => {
console.error(err) //log errors
if (err.status) {
//detailed error message with specific status code
return res.status(err.status).json({
detail: err.message
})
}
//handle generic errors
res.status(500).json({
detail: 'Internal server error'
})
})
Contribution
- Project repository: https://github.com/GFTNetwork/stellar-federation-resolver-node
- Issue tracker: https://github.com/GFTNetwork/stellar-federation-resolver-node/issues
Tests
npm test
How can I help
Primary tasks:
- Create providers with simplistic configuration for Sequelize and Mongoose ORMs (see Go implementation).
- Implement
forward
requests. - Add examples for usage with other web-frameworks.
License
(The MIT License)
Copyright (c) 2017 GFT Network <astro@gft.network>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.