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javascriptreactjssmartcontractsalchemy

× Error: Alchemy URL protocol must be one of http, https, ws, or wss. Recieved: undefined React.js

I just clone smart contract react application in VS code and installed node modules. When i try to npm start, it gave me the error " Error: Alchemy URL protocol must be one of http, https, ws, or wss. Recieved: undefined React.js".

How can i solve this problem? Thanks

Solution

  • According to the Alchemy documentation,

    using websockets with the web3-alchemy sdk requires setting up your web3 object with a websocket URL, like this:

    const { createAlchemyWeb3 } = require("@alch/alchemy-web3");

const web3 = createAlchemyWeb3("wss://eth-mainnet.ws.alchemyapi.io/ws/<api-key>");

    when it is set up correctly, you should be able to make a call, for example:

    web3.eth.getBlockNumber().then(console.log);  // -> 7946893

    The error you are seeing is due to an incorrect argument undefined React.js being passed into the alchemy web3 instantiation, basically:

    const web3 = createAlchemyWeb3( undefined React.js ); // the error is here

    You need to figure out why there is an undefined React.js showing up, and once you fix that error, your app should be able to load!