TCP

Overview

You can also interact with Stellar using a persistent connection through a TCP socket. By default port 5000 is used, but this can be changed by setting the api.config.tcp.port property. Since this is a persistent connection verbs are used to send commands to the server. The list below shows all available verbs:

• quit: disconnects from the server (the session is destroyed)
• paramAdd: saves a single variable to your connection
  • Example: paramAdd query=something
• paramView: returns the details of a single param
  • Example: paramView query
• paramDelete: deletes a single param
  • Example: paramDelete query
• paramsView: returns a JSON object of all the params set in this connection
• paramsDelete: deletes all params set in this session
• detailsView: shows you details about your connection, including about the members currently in the room
• roomAdd: connects to a room
• roomLeave <room>: leaves the room you are connected to
• roomView <room>: shows you the room you are connected to, and information about the members currently in that room
• say <room,> <message>: sends a message to a room

Note: the parameters added in previous calls are fixed to the connection; this means that it is necessary to remove the parameters before calling new verbs.

One of the main advantages of using a TCP connection is the possibility to call several actions simultaneously. Stellar keeps a count of the calls, so you can keep track of the different calls in progress.

TLS

The TCP server supports encrypted connections via TLS, if desired. For this you need to configure some settings on the server:

'use strict'

exports.default = {
  servers: {
    socket: api => {
      secure: true,
      key: fs.readFileSync('certs/server-key.pem'),
      cert: fs.readFileSync('certs/server-cert.pem')
    }
  }
}

The secure connection can be tested using the following command:

$ openssl s_client -connect 127.0.0.1:5000

Or, you can use another node process:

let fs = require('fs')
let tls = require('tls')

let options = {
  key: fs.readFileSync('certs/server-key.pem'),
  cert: fs.readFileSync('certs/server-cert.pem')
}

let socket = tls.connect(5000, options, () => {
  console.log('client', socket.authorized ? 'authorized' : 'not authorized')
})

socket.setEnconding('utf8')
socket.on('data', data => console.log(data))

JSON

The default way to execute actions on Stellar via a TCP connection is using the verbs available for persistent connections. However, it is also possible to use JSON to choose the action to execute and pass a list of parameters. For example, {"action": "actionName", "params": {"key": "some_value"}}.