Fis-Retransmission/test/grpc1.ts

import { Subject, from, take, takeUntil } from "rxjs";
import { GrpcService } from "../services/grpc.service";
import * as fs from 'fs'
import { FisRetransmissionService } from "../services/fis.retransmission.service";
import { ReportStatus } from "../interfaces/general.interface";

const messagesJSON: any = fs.readFileSync('payload.json')
const errorHandlingService: FisRetransmissionService = new FisRetransmissionService()
const gprcService: GrpcService = new GrpcService()
let incomingRequest: Subject<any> = gprcService.getIncomingRequest()
let applicationOutgoingResponse: Subject<any> = new Subject()
let parsedMessages: any[] = JSON.parse(messagesJSON) // load the fake messages generated for this trial 
let dataMessages = stream() // Emulate messges to be sent over to target server
let messageToBePublished: Subject<any> = new Subject()
let statusControl: Subject<ReportStatus> = new Subject()

incomingRequest.subscribe({
  next: request => { // this whole thing is for 1 request
    if (request.id == '0000') {
      console.log(`Just checking for buffer. Dont do anything else!`)
    } else {
      generateFakeStreamResponse(request).subscribe({
        next: (responseMessage) => {
          // console.log(`Processing request:${request.id}....`)
          applicationOutgoingResponse.next(responseMessage)
        },
        error: error => console.error(error),
        complete: () => {
          console.log(`Stream request for ${request.id} is queued.`) // shpuld be indefinite
        }
      })
    }
  },
  error: error => console.error(error),
  complete: () => console.log(`Response for incoming generated. But this will never stop, and should not either.`)
})

/* For server streaming */
errorHandlingService.handleMessage(applicationOutgoingResponse, statusControl).subscribe((messages) => {
  messageToBePublished.next(messages)
})
let server1 = 'localhost:3000'
gprcService.createGrpcInstance(server1, messageToBePublished, statusControl, { instanceType: 'server', serviceMethod: 'server streaming' })


// this is just to publish an array of fake data as a Subject
function stream(): Subject<any> {
  let result: Subject<any> = new Subject()
  let messages: any[] = parsedMessages
  let count = 0
  const intervalId = setInterval(() => {
    result.next(messages[count]);
    count++;
    if (count >= 1000) {
      clearInterval(intervalId);
      result.complete();
    }
  }, 500)

  return result
}

function generateFakeStreamResponse(request: any): Subject<any> {
  let res: Subject<any> = new Subject()
  stream().pipe(take(10)).subscribe({
    next: element => {
      let message = {
        id: request.id, // Caller's 
        message: element
      }
      res.next(message)
    },
    error: error => console.error(error),
    complete: () => console.log(`Stream response for ${request.id} has been prepared.`)
  })
  return res
}