use await inside callback (Microsoft Bot Framework v4 nodejs)

Question

I am trying to send the response back to chatbot emulator from inside callback.

async getUserDetails(step){
    console.log("inside get userdetaiuls modeiule")
    this.userDBObject.password = step.result;

   this.userDBMethod ( async function(response){
        console.log("inside callback return");
        console.log(response);
        await step.context.sendActivity(response); // not able to do this step
        return step.endDialog();
    });
}
async userDBMethod(callback){
request.post('#', 
        {form:{key: 'hi'}}, function (error, response, body) {
        callback("done");
});
}

The error which I'm getting is:

(node:17424) UnhandledPromiseRejectionWarning: TypeError: Cannot perform 'get' on a proxy that has been revoked at D:\LCI\Usecases\statementBalance\lionsbot-src\bot.js:384:32 at Request._callback (D:\LCI\Usecases\statementBalance\lionsbot-src\bot.js:410:17) at Request.self.callback (D:\LCI\Usecases\statementBalance\lionsbot-src\node_modules\request\request.js:185:22) at Request.emit (events.js:182:13) at Request.EventEmitter.emit (domain.js:442:20) at Request. (D:\LCI\Usecases\statementBalance\lionsbot-src\node_modules\request\request.js:1161:10) at Request.emit (events.js:182:13) at Request.EventEmitter.emit (domain.js:442:20) at IncomingMessage. (D:\LCI\Usecases\statementBalance\lionsbot-src\node_modules\request\request.js:1083:12) at Object.onceWrapper (events.js:273:13) (node:17424) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1) (node:17424) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

So how can I use await inside callback to send response back to the user. Thanks !

but right now important task is to send back the user response. which is in await step.context.sendActivity(response); — Sachin Sharma

tdurnford tdurnford · Accepted Answer · 2019-03-06T17:22:24

I would recommend using Axios - a promise based HTTP client for node.js - rather than the request package. Since Axios is promise based, you can use async/await instead of callbacks. The resulting code falls more in line with the flow of the BotFramework. For more details, see the code snippet below and the Axios Documentation.

async getUserDetails(step){
    this.userDBObject.password = step.result;
    try {
        const res = await axios.post('#', {form:{key: 'hi'}});
        await step.context.sendActivity("Done");
    } catch (error) {
        console.log(error);
        await step.context.sendActivity("Sorry, we were not able to complete your request.");
    } 
    return step.endDialog();
}

use await inside callback (Microsoft Bot Framework v4 nodejs)

1 Answers