How to use the @opentelemetry/node.NodeTracerProvider function in @opentelemetry/node

// Used by e2e tests, only needs to build and push image when there is changes,
// by running:
//      make docker.build-bookstore
//      make docker.push-bookstore

'use strict';

const opentelemetry = require('@opentelemetry/api');
const { NodeTracerProvider } = require('@opentelemetry/node');
const { BatchSpanProcessor } = require('@opentelemetry/tracing');
const { TraceExporter } = require('@google-cloud/opentelemetry-cloud-trace-exporter');
const { AlwaysOnSampler, AlwaysOffSampler, ParentOrElseSampler } = require("@opentelemetry/core");
const { HttpTraceContext } = require("@opentelemetry/core");

// Initialize the OpenTelemetry APIs to use the NodeTracerProvider bindings
const provider = new NodeTracerProvider({
  // TODO(nareddyt): Only sample when the incoming request creates a new span.
  // Otherwise don't make new spans, but propagate the context.
  // sampler: new ParentOrElseSampler(new AlwaysOffSampler()),
  sampler: new AlwaysOnSampler(),
  plugins: {
    express: {
      enabled: true,
      path: '@opentelemetry/plugin-express',
      ignoreLayersType: [
          "middleware",
          "request_handler",
      ],
    },
    http: {
      enabled: true,
      path: '@opentelemetry/plugin-http',

}
});
require('@google-cloud/debug-agent').start({
  serviceContext: {
    service: 'currencyservice',
    version: 'VERSION'
  }
});

const opentelemetry = require('@opentelemetry/api');
const {NodeTracerProvider} = require('@opentelemetry/node');
const {BatchSpanProcessor} = require('@opentelemetry/tracing');
const {TraceExporter} = require('@google-cloud/opentelemetry-cloud-trace-exporter');

// OpenTelemetry tracing with exporter to Google Cloud Trace
const provider = new NodeTracerProvider({
  // Use grpc plugin to receive trace contexts from client
  plugins: {
    grpc: {
      enabled: true,
      path: '@opentelemetry/plugin-grpc',
    }
  }
});
// Cloud Trace Exporter handles credentials.
const exporter = new TraceExporter();
provider.addSpanProcessor(new BatchSpanProcessor(exporter));
provider.register();
const tracer = opentelemetry.trace.getTracer('currency');

const path = require('path');
const grpc = require('grpc');

module.exports = () => {
    const provider = new NodeTracerProvider({
        // Use grpc plugin to receive trace contexts from client (checkout)
        plugins: {
            grpc: {
                enabled: true,
                path: '@opentelemetry/plugin-grpc',
            }
        }
    });
    provider.addSpanProcessor(new BatchSpanProcessor(new TraceExporter()));

    // Initialize the OpenTelemetry APIs to use the NodeTracerProvider bindings
    provider.register();

    return opentelemetry.trace.getTracer('payment');
}