func addsvcFactory(makeEndpoint func(addsvc.Service) endpoint.Endpoint, tracer stdopentracing.Tracer, logger log.Logger) sd.Factory {
return func(instance string) (endpoint.Endpoint, io.Closer, error) {
// We could just as easily use the HTTP or Thrift client package to make
// the connection to addsvc. We've chosen gRPC arbitrarily. Note that
// the transport is an implementation detail: it doesn't leak out of
// this function. Nice!
conn, err := grpc.Dial(instance, grpc.WithInsecure())
if err != nil {
return nil, nil, err
}
service := addsvcgrpcclient.New(conn, tracer, logger)
endpoint := makeEndpoint(service)
// Notice that the addsvc gRPC client converts the connection to a
// complete addsvc, and we just throw away everything except the method
// we're interested in. A smarter factory would mux multiple methods
// over the same connection. But that would require more work to manage
// the returned io.Closer, e.g. reference counting. Since this is for
// the purposes of demonstration, we'll just keep it simple.
return endpoint, conn, nil
}
}
func main() {
var (
transport = flag.String("transport", "httpjson", "httpjson, grpc, netrpc, thrift")
httpAddr = flag.String("http.addr", "localhost:8001", "Address for HTTP (JSON) server")
grpcAddr = flag.String("grpc.addr", "localhost:8002", "Address for gRPC server")
netrpcAddr = flag.String("netrpc.addr", "localhost:8003", "Address for net/rpc server")
thriftAddr = flag.String("thrift.addr", "localhost:8004", "Address for Thrift server")
thriftProtocol = flag.String("thrift.protocol", "binary", "binary, compact, json, simplejson")
thriftBufferSize = flag.Int("thrift.buffer.size", 0, "0 for unbuffered")
thriftFramed = flag.Bool("thrift.framed", false, "true to enable framing")
)
flag.Parse()
if len(os.Args) < 4 {
fmt.Fprintf(os.Stderr, "\n%s [flags] method arg1 arg2\n\n", filepath.Base(os.Args[0]))
flag.Usage()
os.Exit(1)
}
root := context.Background()
method, s1, s2 := flag.Arg(0), flag.Arg(1), flag.Arg(2)
var logger log.Logger
logger = log.NewLogfmtLogger(os.Stdout)
logger = log.NewContext(logger).With("caller", log.DefaultCaller)
logger = log.NewContext(logger).With("transport", *transport)
var svc server.AddService
switch *transport {
case "grpc":
cc, err := grpc.Dial(*grpcAddr)
if err != nil {
_ = logger.Log("err", err)
os.Exit(1)
}
defer cc.Close()
svc = grpcclient.New(root, cc, logger)
case "httpjson":
rawurl := *httpAddr
if !strings.HasPrefix("http", rawurl) {
rawurl = "http://" + rawurl
}
baseurl, err := url.Parse(rawurl)
if err != nil {
_ = logger.Log("err", err)
os.Exit(1)
}
svc = httpjsonclient.New(root, baseurl, logger, nil)
case "netrpc":
cli, err := rpc.DialHTTP("tcp", *netrpcAddr)
if err != nil {
_ = logger.Log("err", err)
os.Exit(1)
}
defer cli.Close()
svc = netrpcclient.New(cli, logger)
case "thrift":
var protocolFactory thrift.TProtocolFactory
switch *thriftProtocol {
case "compact":
protocolFactory = thrift.NewTCompactProtocolFactory()
case "simplejson":
protocolFactory = thrift.NewTSimpleJSONProtocolFactory()
case "json":
protocolFactory = thrift.NewTJSONProtocolFactory()
case "binary", "":
protocolFactory = thrift.NewTBinaryProtocolFactoryDefault()
default:
_ = logger.Log("protocol", *thriftProtocol, "err", "invalid protocol")
os.Exit(1)
}
var transportFactory thrift.TTransportFactory
if *thriftBufferSize > 0 {
transportFactory = thrift.NewTBufferedTransportFactory(*thriftBufferSize)
} else {
transportFactory = thrift.NewTTransportFactory()
}
if *thriftFramed {
transportFactory = thrift.NewTFramedTransportFactory(transportFactory)
}
transportSocket, err := thrift.NewTSocket(*thriftAddr)
if err != nil {
_ = logger.Log("during", "thrift.NewTSocket", "err", err)
os.Exit(1)
}
trans := transportFactory.GetTransport(transportSocket)
defer trans.Close()
if err := trans.Open(); err != nil {
_ = logger.Log("during", "thrift transport.Open", "err", err)
os.Exit(1)
}
cli := thriftadd.NewAddServiceClientFactory(trans, protocolFactory)
svc = thriftclient.New(cli, logger)
default:
_ = logger.Log("err", "invalid transport")
os.Exit(1)
}
begin := time.Now()
switch method {
case "sum":
a, _ := strconv.Atoi(s1)
b, _ := strconv.Atoi(s2)
v := svc.Sum(a, b)
_ = logger.Log("method", "sum", "a", a, "b", b, "v", v, "took", time.Since(begin))
case "concat":
a, b := s1, s2
v := svc.Concat(a, b)
_ = logger.Log("method", "concat", "a", a, "b", b, "v", v, "took", time.Since(begin))
default:
_ = logger.Log("err", "invalid method "+method)
os.Exit(1)
}
}
func main() {
// The addcli presumes no service discovery system, and expects users to
// provide the direct address of an addsvc. This presumption is reflected in
// the addcli binary and the the client packages: the -transport.addr flags
// and various client constructors both expect host:port strings. For an
// example service with a client built on top of a service discovery system,
// see profilesvc.
var (
httpAddr = flag.String("http.addr", "", "HTTP address of addsvc")
grpcAddr = flag.String("grpc.addr", "", "gRPC (HTTP) address of addsvc")
thriftAddr = flag.String("thrift.addr", "", "Thrift address of addsvc")
thriftProtocol = flag.String("thrift.protocol", "binary", "binary, compact, json, simplejson")
thriftBufferSize = flag.Int("thrift.buffer.size", 0, "0 for unbuffered")
thriftFramed = flag.Bool("thrift.framed", false, "true to enable framing")
zipkinAddr = flag.String("zipkin.addr", "", "Enable Zipkin tracing via a Kafka Collector host:port")
appdashAddr = flag.String("appdash.addr", "", "Enable Appdash tracing via an Appdash server host:port")
lightstepToken = flag.String("lightstep.token", "", "Enable LightStep tracing via a LightStep access token")
method = flag.String("method", "sum", "sum, concat")
)
flag.Parse()
if len(flag.Args()) != 2 {
fmt.Fprintf(os.Stderr, "usage: addcli [flags] <a> <b>\n")
os.Exit(1)
}
// This is a demonstration client, which supports multiple tracers.
// Your clients will probably just use one tracer.
var tracer stdopentracing.Tracer
{
if *zipkinAddr != "" {
collector, err := zipkin.NewKafkaCollector(
strings.Split(*zipkinAddr, ","),
zipkin.KafkaLogger(log.NewNopLogger()),
)
if err != nil {
fmt.Fprintf(os.Stderr, "%v\n", err)
os.Exit(1)
}
tracer, err = zipkin.NewTracer(
zipkin.NewRecorder(collector, false, "localhost:8000", "addcli"),
)
if err != nil {
fmt.Fprintf(os.Stderr, "%v\n", err)
os.Exit(1)
}
} else if *appdashAddr != "" {
tracer = appdashot.NewTracer(appdash.NewRemoteCollector(*appdashAddr))
} else if *lightstepToken != "" {
tracer = lightstep.NewTracer(lightstep.Options{
AccessToken: *lightstepToken,
})
defer lightstep.FlushLightStepTracer(tracer)
} else {
tracer = stdopentracing.GlobalTracer() // no-op
}
}
// This is a demonstration client, which supports multiple transports.
// Your clients will probably just define and stick with 1 transport.
var (
service addsvc.Service
err error
)
if *httpAddr != "" {
service, err = httpclient.New(*httpAddr, tracer, log.NewNopLogger())
} else if *grpcAddr != "" {
conn, err := grpc.Dial(*grpcAddr, grpc.WithInsecure(), grpc.WithTimeout(time.Second))
if err != nil {
fmt.Fprintf(os.Stderr, "error: %v", err)
os.Exit(1)
}
defer conn.Close()
service = grpcclient.New(conn, tracer, log.NewNopLogger())
} else if *thriftAddr != "" {
// It's necessary to do all of this construction in the func main,
// because (among other reasons) we need to control the lifecycle of the
// Thrift transport, i.e. close it eventually.
var protocolFactory thrift.TProtocolFactory
switch *thriftProtocol {
case "compact":
protocolFactory = thrift.NewTCompactProtocolFactory()
case "simplejson":
protocolFactory = thrift.NewTSimpleJSONProtocolFactory()
case "json":
protocolFactory = thrift.NewTJSONProtocolFactory()
case "binary", "":
protocolFactory = thrift.NewTBinaryProtocolFactoryDefault()
default:
fmt.Fprintf(os.Stderr, "error: invalid protocol %q\n", *thriftProtocol)
os.Exit(1)
}
var transportFactory thrift.TTransportFactory
if *thriftBufferSize > 0 {
transportFactory = thrift.NewTBufferedTransportFactory(*thriftBufferSize)
} else {
transportFactory = thrift.NewTTransportFactory()
}
if *thriftFramed {
transportFactory = thrift.NewTFramedTransportFactory(transportFactory)
}
transportSocket, err := thrift.NewTSocket(*thriftAddr)
if err != nil {
fmt.Fprintf(os.Stderr, "error: %v\n", err)
os.Exit(1)
}
transport := transportFactory.GetTransport(transportSocket)
if err := transport.Open(); err != nil {
fmt.Fprintf(os.Stderr, "error: %v\n", err)
os.Exit(1)
}
defer transport.Close()
client := thriftadd.NewAddServiceClientFactory(transport, protocolFactory)
service = thriftclient.New(client)
} else {
fmt.Fprintf(os.Stderr, "error: no remote address specified\n")
os.Exit(1)
}
if err != nil {
fmt.Fprintf(os.Stderr, "error: %v\n", err)
os.Exit(1)
}
switch *method {
case "sum":
a, _ := strconv.ParseInt(flag.Args()[0], 10, 64)
b, _ := strconv.ParseInt(flag.Args()[1], 10, 64)
v, err := service.Sum(context.Background(), int(a), int(b))
if err != nil {
fmt.Fprintf(os.Stderr, "error: %v\n", err)
os.Exit(1)
}
fmt.Fprintf(os.Stdout, "%d + %d = %d\n", a, b, v)
case "concat":
a := flag.Args()[0]
b := flag.Args()[1]
v, err := service.Concat(context.Background(), a, b)
if err != nil {
fmt.Fprintf(os.Stderr, "error: %v\n", err)
os.Exit(1)
}
fmt.Fprintf(os.Stdout, "%q + %q = %q\n", a, b, v)
default:
fmt.Fprintf(os.Stderr, "error: invalid method %q\n", method)
os.Exit(1)
}
}