# Truffle DappChain Example This simple example shows how you can use `Truffle` and the zeknd Truffle Provider to build a simple Web UI that interacts with the Basechain. \ \&#xNAN;**#Requirements** Make sure the following requirements are met and then follow the steps in the next section: ``` Node >= 8 yarn or npm ``` ### #Install First, let's clone this repository. Open a terminal, `cd` into the directory where you store your projects, and run the following command: ``` git clone https://github.com/zekndnetwork/truffle-dappchain-example ``` Next, `cd` into `truffle-dappchain-example`: ``` cd truffle-dappchain-example ``` and run: ``` yarn install ``` ### #Run against Extdev Testnet #### #Generate the zeknd private key The following command will download the zeknd binary and generate the private key for you: ``` yarn gen:extdev-key ``` > The zeknd private key will be saved into a file called `extdev_private_key`. #### #Deploy to Extdev Testnet As an example, we will deploy and run our application against Extdev. Run the following command: ``` yarn deploy:extdev ``` > The above command will **compile and then deploy** our smart contract to Extdev #### #Test Run this command below to send transactions to the smart contract deployed to Extdev: ``` yarn test:extdev ``` If everything looks good, let's spin up a web server and interact with our smart contract. #### #Start the web interface The web interface is built with React and Webpack. Open a new terminal and run the following command: ``` yarn serve:extdev ``` > The web interface is available on . ### #Run against local zeknd chain First, you have to generate a private key using: ``` yarn gen:extdev-key ``` #### #Spin up zeknd Chain In a new terminal, run: ``` yarn zeknd-init ``` #### #Deploy the smart contract To deploy, run the following command: ``` yarn deploy ``` You will see something like this: ``` Starting migrations... ====================== > Network name: 'zeknd_dapp_chain' > Network id: 13654820909954 > Block gas limit: 0 ``` Copy the `Network id` paste it into a text file. We'll use it later. #### #Test ``` yarn test ``` ### #Web interface Open the `src/contract.js` file in your text editor of choice and go to line 87. Now, say your `Network id` is `13654820909954`. Replace ``` return Promise.resolve('default') ``` with ``` return Promise.resolve('13654820909954') ``` We're ready to start the web server. In a new terminal, run: ``` yarn serve ``` ### #Useful information 1. In order to correctly redeploy the contracts, there's a command `yarn deploy:reset`. 2. Also is possible to call truffle command directly with `yarn truffle`. 3. We're not versioning the build directory for this particular example, although is recommended to versioning, the limitation can be removed by editing the `.gitignore` file. ### #Current limitations * Events declared on smart contracts should have an named parameter like `NewValueSet(uint _value)` in the contract `SimpleStore.sol`. Also, it helps in dealing with events. ### #zeknd Network ### #License BSD 3-Clause License --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://developer.opzeknd.xyz/solidity-and-evm/truffle-dappchain-example.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.