Skip to content

Latest commit

 

History

History
 
 

D21_deploy_contract

Folders and files

NameName
Last commit message
Last commit date

parent directory

..
Contracts
Contracts
 
 
README.md
README.md
 
 
deploy_contract.py
deploy_contract.py
 
 

README.md

EthUtilityServer

The Utility server has two roles. The first role is to help deploy smart contract, and the second role is to provide contract addresses to others. In Ethereum, once a contract has been deployed, it will be assigned an address. Users need to know this address to interact with the contract. The Utility server hosts a web server for others to register contract addresses.

Create Utility Server

We first need to add a Utility server to a blockchain. This example uses a pre-built block component (D00_ethereum_poa), which already has a Utility server. In the D00_ethereum_poa example, these lines are used to create a utility server

util_server:EthUtilityServer = blockchain.createEthUtilityServer(
           vnode='utility',
           port=5000,
           linked_eth_node='eth6',
           linked_faucet_node='faucet')

We can specify the following parameters:

  • vnode: the virtual node name of the Utility server.
  • port: a port number, used by the server to set up a web server.
  • linked_eth_node: the faucet server needs to link to an eth node, so it can sends out transactions to the blockchain. We just need to provide the name of an existing eth node, but we need to make sure that the eth node has enabled the http connection (otherwise, it cannot accept external requests).
  • linked_faucet_node: the Utility server will create an Ethereum account, which is used to deploy contracts. The Utility server will use the faucet server to find the account.

Because this server is already created in the base component, we just need to get an instance of this object:

eth        = emu.getLayer('EthereumService')
blockchain = eth.getBlockchainByName(eth.getBlockchainNames()[0])
name       = blockchain.getUtilityServerNames()[0]
utility    = blockchain.getUtilityServerByName(name)

Deploy a contract

To deploy a contract using the Utility server, we need to set abi and bin file. A path can be both relative and absolute.

utility.deployContractByFilePath(contract_name='test',
                        abi_path="./Contracts/contract.abi",
                        bin_path="./Contracts/contract.bin")

It should be noted that the contract deployment will happen after the emulator starts, so this API will set up the contract deployment on the Utility server.

Interact with the Utility server using curl

After the emulator starts, we can interact with the Utility server using the curl command. To do that, we first need to get the server's IP address (the port number used in the example is 5000).

$ docker ps | grep -i utility
e22e918b4c90   output_hnode_150_host_0  ...  as162h-UtilityServer-10.150.0.71

In this example, the url of the server is http://10.150.0.71:5000/.

Register a contract

To register a contract with the Utility server, we use a POST request to send the contract information (JSON format) to the server's /register_contract API. See the following example:

curl -X POST \
  -H "Content-Type: application/json" \
  -d '{"contract_name": "test999", "contract_address": "0xc0ffee254729296a45a3885639AC7E10F9d54979"}' \
  http://10.150.0.71:5000/register_contract

Get a list of registered contracts

We can use the following API to get a list of all the registered contracts.

curl http://10.150.0.71:5000/all
curl http://10.150.0.71:5000/contracts_info

Get a contract address by its name

If we just want to get the address of a particular contract, we can provide the name argument.

curl http://10.150.0.71:5000/contracts_info?name=test

Interact with the Utility server using Python

We can write Python programs to interact with the Utility server. A helper class called UtilityServerHelper.py is created to make writing such programs easier.