There are other questions similar to this one but not a single one of them helped me visualize my mistake.

I have this code:

function calc() {
    return new Promise(resolve => {
        setTimeout(() => {
            resolve('block finished');
        }, 5000);
      });
}

async function asyncBlock() {
    let result = await calc();
    console.log('Result: '   result);
    return result;
}

app.get('/block', (req, res) => {
    let result = asyncBlock();
    console.log('Already returned the response without the result.');
    res.send(result);
})

app.listen(port, () => {
    console.log(`Example app listening on port ${port}`)
})

The execution continues without the await response, giving me this output:

Example app listening on port 3000
Already returned the response without the result.
Result: block finished

Mozilla documentations states that

If a Promise is passed to an await expression, it waits for the Promise to be fulfilled and returns the fulfilled value.

Mozilla Doc

CodePudding user response：

Your call to AsyncBlock isn't asynchronous.

Try this:

app.get('/block', async (req, res) => {
    let result = await asyncBlock();
    console.log('Waited for the result');
    res.send(result);
})