main.go

package main

import (
	"context"
	"database/sql"
	"fmt"
	"os"

	"net"
	"net/http"
	"simplebank/api"
	db "simplebank/db/sqlc"
	"simplebank/gapi"
	"simplebank/pb"
	"simplebank/util"
	"simplebank/worker"

	"github.com/golang-migrate/migrate/v4"
	_ "github.com/golang-migrate/migrate/v4/database/postgres"
	_ "github.com/golang-migrate/migrate/v4/source/file"
	"github.com/grpc-ecosystem/grpc-gateway/v2/runtime"
	"github.com/hibiken/asynq"
	_ "github.com/lib/pq"
	"github.com/rs/zerolog"
	"github.com/rs/zerolog/log"
	"google.golang.org/grpc"
	"google.golang.org/grpc/reflection"
	"google.golang.org/protobuf/encoding/protojson"
)

func main() {
	config, err := util.LoadConfig(".")
	if err != nil {
		log.Fatal().Msg("cannot load configurations")
	}

	if config.Environment == "development" {
		log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr})
	}

	conn, err := sql.Open(config.DBDriver, config.DBSource)
	if err != nil {
		log.Fatal().Msg("failed to make a connection")
	}

	runDbMigration(config.MigrationURL, config.DBSource)

	store := db.NewStore(conn)
	redisOpt := asynq.RedisClientOpt{
		Addr: config.RedisAddress,
	}

	taskDistributor := worker.NewRedisTaskDistributor(redisOpt)

	go runGatewayServer(config, store, taskDistributor)
	go runTaskProcessor(redisOpt, store)
	runGrpcServer(config, store, taskDistributor)
}

func runGrpcServer(config util.Config, store db.Store, taskDistributor worker.TaskDistributor) {
	server, err := gapi.NewServer(config, store, taskDistributor)
	if err != nil {
		log.Fatal().Msg("cannot create serve")
	}

	grpcLogger := grpc.UnaryInterceptor(gapi.GrpcLogger)
	grpcServer := grpc.NewServer(grpcLogger)
	pb.RegisterSimplebankServer(grpcServer, server)
	reflection.Register(grpcServer)

	listener, err := net.Listen("tcp", config.GrpcServerAddress)
	if err != nil {
		log.Fatal().Msg("cannot create listener")
	}
	log.Printf("started grpc server at %s", listener.Addr().String())
	err = grpcServer.Serve(listener)
	if err != nil {
		log.Fatal().Msg("cannot start grpc server")
	}
}

func runGatewayServer(config util.Config, store db.Store, taskDistributor worker.TaskDistributor) {
	server, err := gapi.NewServer(config, store, taskDistributor)
	if err != nil {
		log.Fatal().Msg("cannot create server")
	}

	jsonOption := runtime.WithMarshalerOption(runtime.MIMEWildcard, &runtime.JSONPb{
		MarshalOptions: protojson.MarshalOptions{
			UseProtoNames: true,
		},
		UnmarshalOptions: protojson.UnmarshalOptions{
			DiscardUnknown: true,
		},
	})

	grpcMux := runtime.NewServeMux(
		jsonOption,
	)

	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	err = pb.RegisterSimplebankHandlerServer(ctx, grpcMux, server)
	if err != nil {
		log.Fatal().Err(err).Msg("cannot register handler server")
	}

	mux := http.NewServeMux()
	mux.Handle("/", grpcMux)

	listener, err := net.Listen("tcp", config.HttpServerAddress)
	if err != nil {
		log.Fatal().Msg("cannot create listener")
	}

	log.Info().Msgf("started HTTP gateway server at %s", listener.Addr().String())

	handler := gapi.HttpLogger(mux)
	err = http.Serve(listener, handler)
	if err != nil {
		log.Fatal().Msgf("cannot start grpc gateway service %v", err)
	}
}

func runGinServer(config util.Config, store db.Store) {
	server, err := api.NewServer(config, store)
	fmt.Println("config is ", len(config.TokenSymmetricKey))
	if err != nil {
		log.Fatal().Msg("cannot create server")
	}
	serverErr := server.StartServer(config.HttpServerAddress)
	if serverErr != nil {
		log.Fatal().Msg("Failed to start server")
	}
}

func runDbMigration(migrationURL string, dbSource string) {

	m, err := migrate.New(migrationURL, dbSource)
	if err != nil {
		log.Fatal().Msg("cannot create a new migration instance")
	}

	if err = m.Up(); err != nil && err != migrate.ErrNoChange {
		log.Fatal().Msg("failed to run migrate up")
	}

	log.Info().Msg("db migration run successfully")
}

func runTaskProcessor(redisOpt asynq.RedisClientOpt, store db.Store) {
	taskProcessor := worker.NewRedisTaskProcessor(redisOpt, store)
	log.Info().Msg("start task processor")

	err := taskProcessor.Start()
	if err != nil {
		log.Fatal().Err(err).Msg("failed to start task processor")
	}
}