Example App

This example contains an example solidity contract simplestorage and a node.js application that interacts with the contract using burrow.js. It also contains a makefile that will set up a single node chain, deploy the contract using burrow deploy. The node app configures itself to use the the single node chain my looking for account.json and deploy.output.json files that are emitted by burrow deploy and the makefile.

The makefile provides some examples of using the burrow command line tooling and you are invited to modify it for your purposes (i.e. change from linux target to darwin)

Dependencies

To run the makefile you will need to have installed:

GNU Make
Node.js (the node binary)
npm (the node package manager)
jq (the JSON tool)
GO
Solc (solidity compiler)

Burrow will be downloaded for you when using the makefile, but you may override BURROW_BIN and BURROW_ARCH in the makefile to change this behaviour. By default Burrow is downloaded for `Linux_x86_64.

Running the example

All commands should be run from the same directory as this readme file.

Step one

Start the chain

make start_chain

This will install burrow, create a new chain as necessary.

If successful you will see continuous output in your terminal, you can shutdown Burrow by sending the interrupt signal with Ctrl-C, and restart it again with whatever state has accumulated with make start_chain. If you would like to destroy the existing chain and start completely fresh (including deleting keys) run make rechain. If you would like to keep existing keys and chain config run make reset_chain.

You can redeploy the contract (to a new address) with make redeploy. The node app will then use this new contract by reading the address deploy.output.json. Be sure to do this if you wish to modify simplestorage.sol.

Step two

Leave burrow running and in a separate terminal start the app which runs a simple HTTP server with:

make start_app

This will deploy the contract if necessary, install any node dependencies, and then start an expressjs server, which will run until interrupted.

Step three

In a third terminal you may run the following commands that will call the Solidity smart contract using Javascript and burrow module:

# Inspect current value
  $ curl http://127.0.0.1:3000
  
# Set the value to 2000
  $ curl -d '{"value": 2000}' -H "Content-Type: application/json" -X POST http://127.0.0.1:3000
  
# Set the value via a testAndSet operation
  $ curl -d '{"value": 30}' -H "Content-Type: application/json" -X POST http://127.0.0.1:3000/2000
  
# Attempt the same testAndSet which now fails since the value stored is no longer '2000'
  $ curl -d '{"value": 30}' -H "Content-Type: application/json" -X POST http://127.0.0.1:3000/2000
  $ curl http://127.0.0.1:3000

Note: httpie is a useful tool that makes POSTing to JSON endpoints more succinct:

# Inspect current value
  $ http 127.0.0.1:3000
  
# Set the value to 2000
  $ http 127.0.0.1:3000 value=2000
  
# Set the value via a testAndSet operation
  $ http 127.0.0.1:3000/2000 value=30
  
# Attempt the same testAndSet which now fails since the value stored is no longer '2000'
  $ http 127.0.0.1:3000/2000 value=30
  $ http 127.0.0.1:3000

Additional endpoints

Sending value and creating accounts

An endpoint is provided at /send for sending value from the default input account (defined in account.json after making the chain) that can be used with:

# Send 1000 units of native token to D1293FE65A071A9DB539D64858F0A3D4BCAA2EBA
  http :3000/send/D1293FE65A071A9DB539D64858F0A3D4BCAA2EBA amount=1000

Pragati1610 / parallax