Await in ClientBefore Button javascript code error

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Await in ClientBefore Button javascript code error	7/8/2022 4:46:09 PM
PHPRunner General questions
Davor Geci authorDevClub member Hello, what I need to do is to read a serial data string that is coming from a serial port. To do that I follow the instructions from https://web.dev/serial/#read-port I've added a custom button in Add page and in ClientBefore code block I added this code: // Prompt user to select any serial port. const port = await navigator.serial.requestPort(); // Wait for the serial port to open. await port.open({ baudRate: 9600 }); const textDecoder = new TextDecoderStream(); const readableStreamClosed = port.readable.pipeTo(textDecoder.writable); const reader = textDecoder.readable.getReader(); // Listen to data coming from the serial device. while (true) { const { value, done } = await reader.read(); if (done) { // Allow the serial port to be closed later. reader.releaseLock(); break; } // value is a string. console.log(value); } submit(); return false; But getting errors in console: Uncaught SyntaxError: await is only valid in async functions and the top level bodies of modules What I'm doing wrong? Thanks, Davor


	Sergey Kornilov admin 7/8/2022
	Googling the error message points to this article: https://stackoverflow.com/questions/49432579/await-is-only-valid-in-async-function You cannot simply use await in ClientBefore event. According to the aticle there is much more work than that.