Braid JS Client Example

Aim

The aim of this tutorial is to create a small cordite client in node js using braid. We will connect this to the braid endpoint of the emea test node in the cordite test network. We will then proceed to make a few doc type queries and also to create your very own Dao!

At the end of this tutorial you should be comfortable creating javascript cordite clients to call your serverside braid endpoints.

The completed code for this tutorial can be found here.

Pre-requisites

• NodeJS installed on your machine

Steps

1. In a terminal, create a directory in which to put your code and change to that directory

   mkdir braidJsClient
   cd braidJsClient
   

2. Next, initialise a node project:

   > npm init
   This utility will walk you through creating a package.json file.
   It only covers the most common items, and tries to guess sensible defaults.
   
   See `npm help json` for definitive documentation on these fields
   and exactly what they do.
   
   Use `npm install <pkg>` afterwards to install a package and
   save it as a dependency in the package.json file.
   
   Press ^C at any time to quit.
   package name: (wibble) cordite-braid-js-client
   version: (1.0.0)
   description:
   entry point: (index.js) client.js
   test command:
   git repository:
   keywords:
   author:
   license: (ISC)
   About to write to /private/tmp/wibble/package.json:
   
   {
   "name": "cordite-braid-js-client",
   "version": "1.0.0",
   "description": "",
   "main": "client.js",
   "scripts": {
      "test": "echo \"Error: no test specified\" && exit 1"
   },
   "author": "",
   "license": "ISC"
   }
   
   Is this ok? (yes) y
   

3. Install the braid javascript client

   npm install --save braid-client
   

4. Connect braid to the cordite emea test test node

   • create the client.js file we specified above: touch client.js.
   • edit this file to import the dependency and connect to emea test

   const Proxy = require('braid-client').Proxy;
   
   const emea = new Proxy({url: 'https://emea-test.cordite.foundation:8080/api/'}, onOpen, onClose, onError, {strictSSL: false})
   
   function onOpen() {
       console.log("connected")
   }
   
   function onClose() {
       console.log("closed")
   }
   
   function onError(err) {
       console.error(err)
   }
   

   If we run this using node client.js we should get the output: connected!.

5. Next we want to see what is in the braid endpoint. So change the onOpen() function to:

   function onOpen() {
       console.log("connected to the emea test cordite node")
       console.log(JSON.stringify(emea))
       console.log("\ndao functions:")
       Object.getOwnPropertyNames(emea.dao).forEach(f => console.log(f))
       console.log("")
       emea.dao.daoInfo.docs()
   }
   

   This should give the output:

   node client.js
   connected to the emea test cordite node
   {“network”:{},“flows”:{},“ledger”:{},“dao”:{}}
   
   daoFunctions:
   getServiceHub
   voteForProposal
   daoInfo
   createDao
   newMemberProposalsFor
   normalProposalsFor
   modelDataProposalsFor
   createProposal
   createNewMemberProposal
   createRemoveMemberProposal
   acceptNewMemberProposal
   acceptRemoveMemberProposal
   acceptProposal
   voteForMemberProposal
   requestProposalConsistencyCheckFor
   createModelDataProposal
   voteForModelDataProposal
   acceptModelDataProposal
   
   API documentation
   -----------------
   * daoInfo(daoName) => array
   
   @param daoName - string
   

   Which we know means we have four ServiceProxy objects, one each for network, flows, ledger and dao. The second line prints out all the available methods and the last line prints out the docs for the daoInfo method.

6. Finally lets create a dao:

   let saltedDaoName = 'testDao-'+new Date().getTime()
   
   function onOpen() {
       console.log("connected to the emea test cordite node")
   
       emea.dao.daoInfo(saltedDaoName).then(daos => {
           console.log("there were", daos.length, "existing daos with name", saltedDaoName )
   
           return emea.dao.createDao(saltedDaoName, "O=Cordite Metering Notary, OU=Cordite Foundation, L=London,C=GB")
       }).then(dao => {
           console.log(saltedDaoName,"created with key",JSON.stringify(dao.daoKey))
       }).catch(error => {
           console.error(error)
       })
   }
   

   Running this gives us:

   connected to the emea test cordite node
   there were 0 existing doas with name testDao-1524060634372
   testDao-1524060634372 created with key {"name":"testDao-1524060634372","uuid":"f99c32c4-7e9c-4c3a-af99-9765d8e6e5b4","uniqueIdentifier":{"externalId":"testDao-1524060634372","id":"f99c32c4-7e9c-4c3a-af99-9765d8e6e5b4"}}
   

The full code is now:

const Proxy = require('braid-client').Proxy;

const emea = new Proxy({url: 'https://emea-test.cordite.foundation:8080/api/'}, onOpen, onClose, onError, {strictSSL: false})

let saltedDaoName = 'testDao-'+new Date().getTime()

function onOpen() {
    console.log("connected to the emea test cordite node")

    emea.dao.daoInfo(saltedDaoName).then(daos => {
        console.log("there were", daos.length, "existing daos with name", saltedDaoName )

        return emea.dao.createDao(saltedDaoName, "O=Cordite Metering Notary, OU=Cordite Foundation, L=London,C=GB")
    }).then(dao => {
        console.log(saltedDaoName,"created with key",JSON.stringify(dao.daoKey))
    }).catch(error => {
        console.error(error)
    })
}

function onClose() {
    console.log("closed")
}

function onError(err) {
    console.error(err)
}