async-await

问题 Introduction I am getting stuck with database Promises I am using inside the Jest testing framework. Things are running in the wrong order, and following some of my latest changes, Jest is not finishing correctly because an unknown asynchronous operation is not being handled. I am fairly new to Node/Jest. Here is what I am trying to do. I am setting up Jest inside a multiple Docker container environment to call internal APIs in order to test their JSON outputs, and to run service functions in

问题 I have const [data, setData] = useState([]); const getData = async () => { const { data } = await axios.get('/getData'); setData(data.payload); }; and a button to call handleDelete from the backend const handleDelete = async () => { checked.forEach(async (element) => { await axios.delete('/deleteData', { data: { data: element }, }); }); await getData(); console.log(data); }; The data is deleted from the backend, I have components that depends on data in React and for some reason, data is not

问题 Are there any issues with using async / await in a forEach loop? I'm trying to loop through an array of files and await on the contents of each file. import fs from 'fs-promise' async function printFiles () { const files = await getFilePaths() // Assume this works fine files.forEach(async (file) => { const contents = await fs.readFile(file, 'utf8') console.log(contents) }) } printFiles() This code does work, but could something go wrong with this? I had someone tell me that you're not

问题 In Javascript I am used to making API calls, using whatever library, using the await keyword. This effectively implements a promise and prevents the next line of code from executing until that line of code has completed. const response = await fetch("http://some-url.com/endpoint", { /* options */ }); const result = response.json(); This does not seem to be necessary in C#. I can make a thread-blocking call and it won't proceed to the next line without using await at all. var response =

问题 So I have a server listening to RabbitMQ requests: console.log(' [*] Waiting for messages in %s. To exit press CTRL+C', q); channel.consume(q, async function reply(msg) { const mongodbUserId = msg.content.toString(); console.log(' [x] Received %s', mongodbUserId); await exec('./new_user_run_athena.sh ' + mongodbUserId, function( error, stdout, stderr ) { console.log('Running Athena...'); console.log('stdout: ' + stdout); console.log('stderr: ' + stderr); if (error !== null) { console.log(

问题 So I have a server listening to RabbitMQ requests: console.log(' [*] Waiting for messages in %s. To exit press CTRL+C', q); channel.consume(q, async function reply(msg) { const mongodbUserId = msg.content.toString(); console.log(' [x] Received %s', mongodbUserId); await exec('./new_user_run_athena.sh ' + mongodbUserId, function( error, stdout, stderr ) { console.log('Running Athena...'); console.log('stdout: ' + stdout); console.log('stderr: ' + stderr); if (error !== null) { console.log(

问题 I'm refactoring my framework with protractor Async/Await to avoid sloppy browser.sleep() all over the code base. Following are the steps of test followed by code as an example: Opens ChromeBrowser Logins with the credentials Selects a customer Clicks on "Manage Customer" button. Could you please help me with below Error: Report destination: target\e2e\screenshots\my-report.html [12:42:21] I/launcher - Running 1 instances of WebDriver [12:42:21] I/hosted - Using the selenium server at http:/

问题 I'm refactoring my framework with protractor Async/Await to avoid sloppy browser.sleep() all over the code base. Following are the steps of test followed by code as an example: Opens ChromeBrowser Logins with the credentials Selects a customer Clicks on "Manage Customer" button. Could you please help me with below Error: Report destination: target\e2e\screenshots\my-report.html [12:42:21] I/launcher - Running 1 instances of WebDriver [12:42:21] I/hosted - Using the selenium server at http:/

问题 I'm writing a Python program to interact with a device based on a CAN Bus. I'm using the python-can module successfully for this purpose. I'm also using asyncio to react to asynchronous events. I have written a "CanBusManager" class that is used by the "CanBusSequencer" class. The "CanBusManager" class takes care of generating/sending/receiving messages, and the CanBusSequencer drives the sequence of messages to be sent. At some point in the sequence I want to wait until a specific message is

问题 I'm writing a Python program to interact with a device based on a CAN Bus. I'm using the python-can module successfully for this purpose. I'm also using asyncio to react to asynchronous events. I have written a "CanBusManager" class that is used by the "CanBusSequencer" class. The "CanBusManager" class takes care of generating/sending/receiving messages, and the CanBusSequencer drives the sequence of messages to be sent. At some point in the sequence I want to wait until a specific message is