How to use WalletConnect with Angular app?

Question

Problem: I am trying to use WalletConnect to connect MetaMask wallet in my angular app. I have the following code to connect with the wallet. Everything runs fine until this line in the below code: await connector.createSession();

Does anyone implement WalletConnect with angular and face this issue?

Error:

ERROR Error: Uncaught (in promise): ReferenceError: Buffer is not defined
ReferenceError: Buffer is not defined
    at typedarrayToBuffer (vendor.js:82628:15)
    at arrayToBuffer (vendor.js:61701:71)
    at Module.arrayToHex (vendor.js:61704:24)
    at generateRandomBytes32 (vendor.js:64322:63)
    at vendor.js:56407:96
    at Generator.next (<anonymous>)
    at asyncGeneratorStep (vendor.js:167002:24)
    at _next (vendor.js:167024:9)
    at ZoneDelegate.invoke (polyfills.js:4680:26)
    at Object.onInvoke (vendor.js:137134:25)
    at resolvePromise (polyfills.js:5521:31)
    at resolvePromise (polyfills.js:5475:17)
    at polyfills.js:5587:17
    at ZoneDelegate.invokeTask (polyfills.js:4714:31)
    at Object.onInvokeTask (vendor.js:137122:25)
    at ZoneDelegate.invokeTask (polyfills.js:4713:60)
    at Zone.runTask (polyfills.js:4486:47)
    at drainMicroTaskQueue (polyfills.js:4890:35)
    at ZoneTask.invokeTask [as invoke] (polyfills.js:4799:21)
    at invokeTask (polyfills.js:5908:14)

Code using from WalletConnect documentation:

// Create a connector
    const connector = new WalletConnect({
      bridge: "https://bridge.walletconnect.org", // Required
      qrcodeModal: QRCodeModal,
    });

    // Subscribe to connection events
    connector.on("connect", (error, payload) => {
      if (error) {
        throw error;
      }

      // Get provided accounts and chainId
      const { accounts, chainId } = payload.params[0];
    });

    connector.on("session_update", (error, payload) => {
      if (error) {
        throw error;
      }

      // Get updated accounts and chainId
      const { accounts, chainId } = payload.params[0];
    });

    connector.on("disconnect", (error, payload) => {
      if (error) {
        throw error;
      }

      // Delete connector
    });

    // Check if connection is already established
    if (!connector.connected) {
      // create new session
      await connector.createSession();
    }

Answer 1

In addition to @houmn.sanati answer, I had to do some extra steps.

These are all the steps I took to fix the issue:

• Install buffer package npm install buffer
• Add this line in polyfills.ts file
• Install @types/node npm i --save-dev @types/node
• Add types to your tsconfig.json and tsconfig.app.json(if you have this file) in compilerOptions

{
  ...
  "compilerOptions": {
    ...
    "types": [
      "node"
    ]
  },
  "angularCompilerOptions": {
    ...
  }
}

• (Optional: Only If you face issue with preact package) Add this override for preact package in package.json file

"overrides": {
    "[email protected]": {
      "preact": "10.0.5"
    }
  }

Answer 2

first, install buffer using npm npm install buffer then add this code at the end of polyfills.ts file:

(window as any)['global'] = window;
global.Buffer = global.Buffer || require('buffer').Buffer;