Delta提供了Solidity语言编写的合约，可以部署在支持EVM虚拟机的区块链上。
智能合约的编译和部署需要通过Node.js包truffle来进行。在开始部署以前，需要确认本地安装了Node.js。
下载Delta Contracts源码
Delta Contracts代码库中包含了合约源代码，以及部署合约需要的自动化工具：
$ git clone --depth 1 --branch v0.8.3 https://github.com/delta-mpc/delta-contracts.git
安装依赖
使用npm来安装源代码依赖的其他代码库：
$ npm install -g truffle
在delta-contracts目录下，输入命令：
编译及部署智能合约
编辑.env文件，设置用于部署的账户私钥与地址：
DELTA_PKEY = <your private key>
DELTA_ADDR = <your address>
其中，<your private key>用账户的私钥代替，<your address>用账户的地址代替。账户中需要提前转账，充入以太。转账的操作可以参考启动区块链节点章节：
然后运行下面的命令，编译并部署contracts目录下的智能合约。其中，IdentityContract合约是用来进行节点身份管理的合约，HFLContract合约是用来进行横向联邦学习的合约， DataHub合约是用来进行节点数据管理的合约，HLR合约是用来进行横向逻辑回归的合约，PlonkVerifier3合约是用来验证输入长度为3的零知识证明合约：
$ truffle migrate --network delta
看到如下输出，则表明部署成功：
...
2_deploy_identity.js
====================
Deploying 'IdentityContract'
----------------------------
> transaction hash: 0x3e15146bb32ddfa94dda6d4ae073e198ecabb661d1e41dc34c6429787cda11b0
> Blocks: 0 Seconds: 0
> contract address: 0xCe69c1DDCcD29a821bB4d3BdEEb3EdE9De9C7903
> block number: 3
> block timestamp: 1665558190
> account: 0x3e26599f1B992b75c7A7aDF6c6EeA8d5179EeAe2
> balance: 99.97278602
> gas used: 1164499 (0x11c4d3)
> gas price: 20 gwei
> value sent: 0 ETH
> total cost: 0.02328998 ETH
> Saving migration to chain.
> Saving artifacts
-------------------------------------
> Total cost: 0.02328998 ETH
3_deploy_hfl.js
===============
Deploying 'HFLContract'
-----------------------
> transaction hash: 0xd0d223126c28c9dc48aed6714067c30ba14e4dd2740ab3c99fd7af78aadc826a
> Blocks: 0 Seconds: 0
> contract address: 0x7864Bf464F9ecE0D3A95cA55e171D9060cf7336a
> block number: 5
> block timestamp: 1665558190
> account: 0x3e26599f1B992b75c7A7aDF6c6EeA8d5179EeAe2
> balance: 99.89255696
> gas used: 3984163 (0x3ccb23)
> gas price: 20 gwei
> value sent: 0 ETH
> total cost: 0.07968326 ETH
> Saving migration to chain.
> Saving artifacts
-------------------------------------
> Total cost: 0.07968326 ETH
4_deploy_verifier3.js
=====================
Deploying 'PlonkVerifier3'
--------------------------
> transaction hash: 0xb99668bf525e660442e2683852522850b2db614871e8a62e4281a241327cd309
> Blocks: 0 Seconds: 0
> contract address: 0x075200EBa6317bE48ED73c04082088fab26f5D02
> block number: 7
> block timestamp: 1665558191
> account: 0x3e26599f1B992b75c7A7aDF6c6EeA8d5179EeAe2
> balance: 99.86093038
> gas used: 1554039 (0x17b677)
> gas price: 20 gwei
> value sent: 0 ETH
> total cost: 0.03108078 ETH
> Saving migration to chain.
> Saving artifacts
-------------------------------------
> Total cost: 0.03108078 ETH
5_deploy_datahub.js
===================
Deploying 'DataHub'
-------------------
> transaction hash: 0x88dbb128fdefc619ae9825fbe59c4ee90f7d591fdbacadb5e5cfa10975c58d2a
> Blocks: 0 Seconds: 0
> contract address: 0x02c1d56eB5C04Cb026cd98Cf38F75A9942EED39B
> block number: 9
> block timestamp: 1665558191
> account: 0x3e26599f1B992b75c7A7aDF6c6EeA8d5179EeAe2
> balance: 99.85419864
> gas used: 309297 (0x4b831)
> gas price: 20 gwei
> value sent: 0 ETH
> total cost: 0.00618594 ETH
> Saving migration to chain.
> Saving artifacts
-------------------------------------
> Total cost: 0.00618594 ETH
6_deploy_hlr.js
===============
Deploying 'HLR'
---------------
> transaction hash: 0x98abca445a9b25833f70ab377d4cf35cdf5791b8ca02f59735503d895dfb03fb
> Blocks: 0 Seconds: 0
> contract address: 0x19eE33EC0eAC58205f1797303461dEa88BFF93E9
> block number: 11
> block timestamp: 1665558192
> account: 0x3e26599f1B992b75c7A7aDF6c6EeA8d5179EeAe2
> balance: 99.74765404
> gas used: 5299940 (0x50dee4)
> gas price: 20 gwei
> value sent: 0 ETH
> total cost: 0.1059988 ETH
> Saving migration to chain.
> Saving artifacts
-------------------------------------
> Total cost: 0.1059988 ETH
...
从上面的输出中，我们可以得到我们部署的智能合约的地址。例如，IdentityContract的合约地址为0xCe69c1DDCcD29a821bB4d3BdEEb3EdE9De9C7903，HFLContract的合约地址为0x7864Bf464F9ecE0D3A95cA55e171D9060cf7336a。
运行完成后，在build/contracts目录下可以看到一系列json文件，包括IdentityContract.json、HFLContract.json、DataHub.json、HLR.json和PlonkVerifier3.json。它们是上述智能合约对应的abi文件。至此智能合约已经部署完成。
在区块链浏览器中添加合约信息
部署完智能合约后，为了方便在区块链浏览器中查看合约调用的数据，可以将合约信息添加到区块链浏览器中。
