percybolmer

// PingCounter is a struct that keeps track of how many Pings that are performed
type PingCounter struct {
	Pings int
}

// ServerCount is a gRPC UnaryServerInterceptor that will count number of API calls.
func (pc *PingCounter) ServerCount(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (response interface{}, err error) {
	// Append to PingCounts
	pc.Pings++
	// We want to extract metadata from the incomming context.

percybolmer

// GenerateTLSApi will load TLS certificates and key and create a grpc server with those.
func GenerateTLSApi(pemPath, keyPath string) (*grpc.Server, error) {
	cred, err := credentials.NewServerTLSFromFile(pemPath, keyPath)
	if err != nil {
		return nil, err
	}

	// Add PingCounter from the interceptors package
	pc := interceptors.PingCounter{}
	s := grpc.NewServer(

percybolmer

// ClientPingCounter is a UnaryClientInterceptor that will count the number of API calls on the Client side
func (pc *PingCounter) ClientPingCounter(ctx context.Context, method string, req interface{}, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
	pc.Pings++
	// Run regular gRPC call after
	// If you dont run the invoker, the gRPC call wont be sent to the server
	return invoker(ctx, method, req, reply, cc, opts...)
}

percybolmer

package main

import (
	"context"
	"crypto/tls"
	"crypto/x509"
	"fmt"
	"io/ioutil"
	"log"

percybolmer

export function GetUser(client, callback) { 
  var user = JSON.parse(localStorage.getItem('user'));
  var userRequest = new UserRequest();
  if (user !== null) { 
    userRequest.setId(user.id);
    var metadata = { "x-user-auth-token": user.token, "x-user-auth-id": user.id, }
    client.getUser(userRequest, metadata, callback);
  }
}

percybolmer

// lets bind a function to change the counter based on the metadata field
request.on('metadata', function(status) {
   // pingCounts are stored in Metadata, and metadata is a key value map
   setServerPings(status['ping-counts']);
})

percybolmer

import './App.css';
import React, {useState, useEffect } from 'react';
import { PingPongClient } from './proto/service_grpc_web_pb';
import { PingRequest } from './proto/service_pb';



 // We create a client that connects to the api
var client = new PingPongClient("https://localhost:8080");

percybolmer

package interceptors

import (
	"context"
	"fmt"

	"google.golang.org/grpc"
)

// LogRequest is a gRPC UnaryServerInterceptor that will log the API call to stdOut

percybolmer

// GenerateTLSApi will load TLS certificates and key and create a grpc server with those.
func GenerateTLSApi(pemPath, keyPath string) (*grpc.Server, error) {
	cred, err := credentials.NewServerTLSFromFile(pemPath, keyPath)
	if err != nil {
		return nil, err
	}

	// Add PingCounter from the interceptors package
	pc := interceptors.PingCounter{}
	s := grpc.NewServer(

percybolmer

package main

import (
	"log"
	"net"
	"net/http"
	"time"

	"github.com/improbable-eng/grpc-web/go/grpcweb"
	"github.com/percybolmer/grpcexample/interceptors"