AWS DAX 客户端 promise() 错误：请求 object 已使用

Question

Thank you. for taking time to read this post.

I an new to JS and stuck in a callback issue related to promise() when querying AWS DAX. There is a post ( using the.promise() call on a dax-services dynamodb document client returns error: Error: ValidationException: Request object already used ) related to this issue but am not able to follow the answer.

I also visited below page but got stuck as the page does not provide a sample for client.send(command) https://www.npmjs.com/package/@aws-sdk/client-dax

I keep getting below error: DaxClientError: ValidationException: Request object already used.

Can you please help correcting below code and with explanation to the solution?

I will truly appreciate your help. I spent an entire day on this but did not make any progress.

 const express = require('express'); const AWS = require('aws-sdk'); const AmazonDaxClient = require('amazon-dax-client'); var region = "us-west-2"; AWS.config.update({ region: region }); const myendpoint = "daxs://mydax.xxxx.dax-clusters.us-west-2.amazonaws.com"; const dax = new AmazonDaxClient({endpoints: [myendpoint], region: region}); // If using AWS.DynamoDB.DocumentClient... const doc = new AWS.DynamoDB.DocumentClient({service: dax}); // Constants const PORT = 8080; const HOST = '0.0.0.0'; // App const app = express(); app.get('/', (req, res) => { res.send('Hello World'); }); app.get('/readreview', async (req, res) => { try{ var myresult='empty'; var params = { TableName: 'test', Key:{ "id": 'p12', "key": 'description' } }; await doc.get(params, function(err, data) { if (err) { console.error("Unable to read item. Error JSON:", JSON.stringify(err, null, 2)); } else { myresult=data; console.log("@@@@@@@@@"+data); } }).promise(); res.send(myresult); } catch (e) { console.log(e); } }); app.listen(PORT, HOST); console.log(`Running on http://${HOST}:${PORT}`);

Thank you!