Checking in cmd files | first attempt at linking up item service

services/character/cmd/character-cli/grpc.go

@@ -0,0 +1,27 @@
+package main
+
+import (
+	cli "crossnokaye-interview-assignment/services/character/gen/grpc/cli/character"
+	"fmt"
+	"os"
+
+	goa "goa.design/goa/v3/pkg"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/credentials/insecure"
+)
+
+func doGRPC(scheme, host string, timeout int, debug bool) (goa.Endpoint, any, error) {
+	conn, err := grpc.Dial(host, grpc.WithTransportCredentials(insecure.NewCredentials()))
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "could not connect to gRPC server at %s: %v\n", host, err)
+	}
+	return cli.ParseEndpoint(conn)
+}
+
+func grpcUsageCommands() string {
+	return cli.UsageCommands()
+}
+
+func grpcUsageExamples() string {
+	return cli.UsageExamples()
+}

services/character/cmd/character-cli/main.go

@@ -0,0 +1,120 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"net/url"
+	"os"
+	"strings"
+
+	goa "goa.design/goa/v3/pkg"
+)
+
+func main() {
+	var (
+		hostF = flag.String("host", "localhost", "Server host (valid values: localhost)")
+		addrF = flag.String("url", "", "URL to service host")
+
+		verboseF = flag.Bool("verbose", false, "Print request and response details")
+		vF       = flag.Bool("v", false, "Print request and response details")
+		timeoutF = flag.Int("timeout", 30, "Maximum number of seconds to wait for response")
+	)
+	flag.Usage = usage
+	flag.Parse()
+	var (
+		addr    string
+		timeout int
+		debug   bool
+	)
+	{
+		addr = *addrF
+		if addr == "" {
+			switch *hostF {
+			case "localhost":
+				addr = "grpc://localhost:8083"
+			default:
+				fmt.Fprintf(os.Stderr, "invalid host argument: %q (valid hosts: localhost)\n", *hostF)
+				os.Exit(1)
+			}
+		}
+		timeout = *timeoutF
+		debug = *verboseF || *vF
+	}
+
+	var (
+		scheme string
+		host   string
+	)
+	{
+		u, err := url.Parse(addr)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "invalid URL %#v: %s\n", addr, err)
+			os.Exit(1)
+		}
+		scheme = u.Scheme
+		host = u.Host
+	}
+	var (
+		endpoint goa.Endpoint
+		payload  any
+		err      error
+	)
+	{
+		switch scheme {
+		case "grpc", "grpcs":
+			endpoint, payload, err = doGRPC(scheme, host, timeout, debug)
+		default:
+			fmt.Fprintf(os.Stderr, "invalid scheme: %q (valid schemes: grpc)\n", scheme)
+			os.Exit(1)
+		}
+	}
+	if err != nil {
+		if err == flag.ErrHelp {
+			os.Exit(0)
+		}
+		fmt.Fprintln(os.Stderr, err.Error())
+		fmt.Fprintln(os.Stderr, "run '"+os.Args[0]+" --help' for detailed usage.")
+		os.Exit(1)
+	}
+
+	data, err := endpoint(context.Background(), payload)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err.Error())
+		os.Exit(1)
+	}
+
+	if data != nil {
+		m, _ := json.MarshalIndent(data, "", "    ")
+		fmt.Println(string(m))
+	}
+}
+
+func usage() {
+	fmt.Fprintf(os.Stderr, `%s is a command line client for the character API.
+
+Usage:
+    %s [-host HOST][-url URL][-timeout SECONDS][-verbose|-v] SERVICE ENDPOINT [flags]
+
+    -host HOST:  server host (localhost). valid values: localhost
+    -url URL:    specify service URL overriding host URL (http://localhost:8080)
+    -timeout:    maximum number of seconds to wait for response (30)
+    -verbose|-v: print request and response details (false)
+
+Commands:
+%s
+Additional help:
+    %s SERVICE [ENDPOINT] --help
+
+Example:
+%s
+`, os.Args[0], os.Args[0], indent(grpcUsageCommands()), os.Args[0], indent(grpcUsageExamples()))
+}
+
+func indent(s string) string {
+	if s == "" {
+		return ""
+	}
+	return "    " + strings.Replace(s, "\n", "\n    ", -1)
+}

services/character/cmd/character/grpc.go

@@ -0,0 +1,81 @@
+package main
+
+import (
+	"context"
+	character "crossnokaye-interview-assignment/services/character/gen/character"
+	characterpb "crossnokaye-interview-assignment/services/character/gen/grpc/character/pb"
+	charactersvr "crossnokaye-interview-assignment/services/character/gen/grpc/character/server"
+	"log"
+	"net"
+	"net/url"
+	"sync"
+
+	grpcmdlwr "goa.design/goa/v3/grpc/middleware"
+	"goa.design/goa/v3/middleware"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/reflection"
+)
+
+// handleGRPCServer starts configures and starts a gRPC server on the given
+// URL. It shuts down the server if any error is received in the error channel.
+func handleGRPCServer(ctx context.Context, u *url.URL, characterEndpoints *character.Endpoints, wg *sync.WaitGroup, errc chan error, logger *log.Logger, debug bool) {
+
+	// Setup goa log adapter.
+	var (
+		adapter middleware.Logger
+	)
+	{
+		adapter = middleware.NewLogger(logger)
+	}
+
+	// Wrap the endpoints with the transport specific layers. The generated
+	// server packages contains code generated from the design which maps
+	// the service input and output data structures to gRPC requests and
+	// responses.
+	var (
+		characterServer *charactersvr.Server
+	)
+	{
+		characterServer = charactersvr.New(characterEndpoints, nil)
+	}
+
+	// Initialize gRPC server with the middleware.
+	srv := grpc.NewServer(
+		grpc.ChainUnaryInterceptor(
+			grpcmdlwr.UnaryRequestID(),
+			grpcmdlwr.UnaryServerLog(adapter),
+		),
+	)
+
+	// Register the servers.
+	characterpb.RegisterCharacterServer(srv, characterServer)
+
+	for svc, info := range srv.GetServiceInfo() {
+		for _, m := range info.Methods {
+			logger.Printf("serving gRPC method %s", svc+"/"+m.Name)
+		}
+	}
+
+	// Register the server reflection service on the server.
+	// See https://grpc.github.io/grpc/core/md_doc_server-reflection.html.
+	reflection.Register(srv)
+
+	(*wg).Add(1)
+	go func() {
+		defer (*wg).Done()
+
+		// Start gRPC server in a separate goroutine.
+		go func() {
+			lis, err := net.Listen("tcp", u.Host)
+			if err != nil {
+				errc <- err
+			}
+			logger.Printf("gRPC server listening on %q", u.Host)
+			errc <- srv.Serve(lis)
+		}()
+
+		<-ctx.Done()
+		logger.Printf("shutting down gRPC server at %q", u.Host)
+		srv.Stop()
+	}()
+}

services/character/cmd/character/main.go

@@ -0,0 +1,109 @@
+package main
+
+import (
+	"context"
+	characterapi "crossnokaye-interview-assignment/services/character"
+	character "crossnokaye-interview-assignment/services/character/gen/character"
+	"flag"
+	"fmt"
+	"log"
+	"net"
+	"net/url"
+	"os"
+	"os/signal"
+	"sync"
+	"syscall"
+)
+
+func main() {
+	// Define command line flags, add any other flag required to configure the
+	// service.
+	var (
+		hostF     = flag.String("host", "localhost", "Server host (valid values: localhost)")
+		domainF   = flag.String("domain", "", "Host domain name (overrides host domain specified in service design)")
+		grpcPortF = flag.String("grpc-port", "", "gRPC port (overrides host gRPC port specified in service design)")
+		secureF   = flag.Bool("secure", false, "Use secure scheme (https or grpcs)")
+		dbgF      = flag.Bool("debug", false, "Log request and response bodies")
+	)
+	flag.Parse()
+
+	// Setup logger. Replace logger with your own log package of choice.
+	var (
+		logger *log.Logger
+	)
+	{
+		logger = log.New(os.Stderr, "[characterapi] ", log.Ltime)
+	}
+
+	// Initialize the services.
+	var (
+		characterSvc character.Service
+	)
+	{
+		characterSvc = characterapi.NewCharacter(logger)
+	}
+
+	// Wrap the services in endpoints that can be invoked from other services
+	// potentially running in different processes.
+	var (
+		characterEndpoints *character.Endpoints
+	)
+	{
+		characterEndpoints = character.NewEndpoints(characterSvc)
+	}
+
+	// Create channel used by both the signal handler and server goroutines
+	// to notify the main goroutine when to stop the server.
+	errc := make(chan error)
+
+	// Setup interrupt handler. This optional step configures the process so
+	// that SIGINT and SIGTERM signals cause the services to stop gracefully.
+	go func() {
+		c := make(chan os.Signal, 1)
+		signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
+		errc <- fmt.Errorf("%s", <-c)
+	}()
+
+	var wg sync.WaitGroup
+	ctx, cancel := context.WithCancel(context.Background())
+
+	// Start the servers and send errors (if any) to the error channel.
+	switch *hostF {
+	case "localhost":
+		{
+			addr := "grpc://localhost:8083"
+			u, err := url.Parse(addr)
+			if err != nil {
+				logger.Fatalf("invalid URL %#v: %s\n", addr, err)
+			}
+			if *secureF {
+				u.Scheme = "grpcs"
+			}
+			if *domainF != "" {
+				u.Host = *domainF
+			}
+			if *grpcPortF != "" {
+				h, _, err := net.SplitHostPort(u.Host)
+				if err != nil {
+					logger.Fatalf("invalid URL %#v: %s\n", u.Host, err)
+				}
+				u.Host = net.JoinHostPort(h, *grpcPortF)
+			} else if u.Port() == "" {
+				u.Host = net.JoinHostPort(u.Host, "8080")
+			}
+			handleGRPCServer(ctx, u, characterEndpoints, &wg, errc, logger, *dbgF)
+		}
+
+	default:
+		logger.Fatalf("invalid host argument: %q (valid hosts: localhost)\n", *hostF)
+	}
+
+	// Wait for signal.
+	logger.Printf("exiting (%v)", <-errc)
+
+	// Send cancellation signal to the goroutines.
+	cancel()
+
+	wg.Wait()
+	logger.Println("exited")
+}