How do you "await" and unsubscribe an Event Emitter checking pending transactions?

[proficy]

I have the following code scanning the pending transaction pool until my wallet is found:

var scanTxPool = async () => {
    var myWallet = '0x0000000000000000000000000000000000000000';
    var foundWallet = false;
    provider.on("pending", async (txHash) => {
        if (!foundWallet) {
            provider.getTransaction(txHash).then(async (tx) => {
                if (tx && tx.to) {
                    if (tx.from === myWallet) {
                        console.log('Found my wallet!');
                        foundWallet = true;
                    }
                }
            });
        }
    });
    // do other stuff 
}

The code is working great but I have two issues:

1. While the pending transactions are run in the background, execution continues to "do other stuff." How can I make sure that the pending transaction check is awaited before do other stuff is executed?
2. Once my wallet is found from the transaction hash I set foundWallet to true so the !foundWallet check stops it from calling getTransaction(txHash). However, the pending txHash check is still executed indefinitely. How can I cleanly end the pending transaction check once my condition has been met?

I've tried creating an else statement and using provider.removeAllListeners() and provider.off() but neither work.

[zemse]

Does this work for you?

var scanTxPool = async () => {
    var myWallet = '0x0000000000000000000000000000000000000000';

    // this waits until resolve() is called
    await new Promise((resolve) => {
      provider.on("pending", async (txHash) => {
            provider.getTransaction(txHash).then(async (tx) => {
                if (tx && tx.to) {
                    if (tx.from === myWallet) {
                        console.log('Found my wallet!');
                        provider.removeAllListeners();
                        resolve();
                    }
                }
            });
      });
    })
    // do other stuff 
}

[proficy]

Sadly, no this didn't work. I stepped through in the debugger and it just kept finding new transaction hashes.

[proficy]

@ricmoo do you have any idea why @zemse's solution isn't working? The best solution I've come up with is exiting the program when my condition has been met.

[proficy]

@zemse my apologies, this code does work! There is only one slight issue. When I run the code in the debugger the program continues to run even when there are no tasks left. If I pause the debugger it's stuck on this function:

        // This Provider does not actually poll, but we want to trigger
        // poll events for things that depend on them (like stalling for
        // block and transaction lookups)
        var fauxPoll = setInterval(function () {
            _this.emit("poll");
        }, 1000);

[proficy]

@zemse or @ricmoo do you have any insight regarding my last question? It looks like there are lingering providers still listening. I've set up some handling with provider._websocket.on("close") and it looks like these faux provider connections keep getting caught. How do I completely close all providers?

[hakanyakar]

worked for me as well thanks.