func main() {
var (
listen = flag.String("listen", ":8080", "HTTP listen address")
proxy = flag.String("proxy", "", "Optional comma-separated list of URLs to proxy uppercase requests")
)
flag.Parse()
var logger log.Logger
logger = log.NewLogfmtLogger(os.Stderr)
logger = log.NewContext(logger).With("listen", *listen).With("caller", log.DefaultCaller)
ctx := context.Background()
fieldKeys := []string{"method", "error"}
requestCount := kitprometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "my_group",
Subsystem: "string_service",
Name: "request_count",
Help: "Number of requests received.",
}, fieldKeys)
requestLatency := kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "my_group",
Subsystem: "string_service",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys)
countResult := kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "my_group",
Subsystem: "string_service",
Name: "count_result",
Help: "The result of each count method.",
}, []string{})
var svc StringService
svc = stringService{}
svc = proxyingMiddleware(*proxy, ctx, logger)(svc)
svc = loggingMiddleware(logger)(svc)
svc = instrumentingMiddleware(requestCount, requestLatency, countResult)(svc)
uppercaseHandler := httptransport.NewServer(
ctx,
makeUppercaseEndpoint(svc),
decodeUppercaseRequest,
encodeResponse,
)
countHandler := httptransport.NewServer(
ctx,
makeCountEndpoint(svc),
decodeCountRequest,
encodeResponse,
)
http.Handle("/uppercase", uppercaseHandler)
http.Handle("/count", countHandler)
http.Handle("/metrics", stdprometheus.Handler())
logger.Log("msg", "HTTP", "addr", *listen)
logger.Log("err", http.ListenAndServe(*listen, nil))
}
func main() {
ctx := context.Background()
logger := log.NewLogfmtLogger(os.Stderr)
fieldKeys := []string{"method", "error"}
requestCount := kitprometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "my_group",
Subsystem: "string_service",
Name: "request_count",
Help: "Number of requests received.",
}, fieldKeys)
requestLatency := kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "my_group",
Subsystem: "string_service",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys)
countResult := kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "my_group",
Subsystem: "string_service",
Name: "count_result",
Help: "The result of each count method.",
}, []string{}) // no fields here
var svc StringService
svc = stringService{}
svc = loggingMiddleware{logger, svc}
svc = instrumentingMiddleware{requestCount, requestLatency, countResult, svc}
uppercaseHandler := httptransport.NewServer(
ctx,
makeUppercaseEndpoint(svc),
decodeUppercaseRequest,
encodeResponse,
)
countHandler := httptransport.NewServer(
ctx,
makeCountEndpoint(svc),
decodeCountRequest,
encodeResponse,
)
http.Handle("/uppercase", uppercaseHandler)
http.Handle("/count", countHandler)
http.Handle("/metrics", stdprometheus.Handler())
logger.Log("msg", "HTTP", "addr", ":8080")
logger.Log("err", http.ListenAndServe(":8080", nil))
}
// NewGauge implements Provider via prometheus.NewSummaryFrom, i.e. the summary
// is registered. The metric's namespace and subsystem are taken from the
// Provider. Help is set to the name of the metric, and no const label names are
// set. Buckets are ignored.
func (p *prometheusProvider) NewHistogram(name string, _ int) metrics.Histogram {
return prometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: p.namespace,
Subsystem: p.subsystem,
Name: name,
Help: name,
}, []string{})
}
func WireUp(ctx context.Context, declineAmount float32) (http.Handler, log.Logger) {
// Log domain.
var logger log.Logger
{
logger = log.NewLogfmtLogger(os.Stderr)
logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
logger = log.NewContext(logger).With("caller", log.DefaultCaller)
}
fieldKeys := []string{"method"}
// Service domain.
var service Service
{
service = NewAuthorisationService(declineAmount)
service = LoggingMiddleware(logger)(service)
service = NewInstrumentingService(
kitprometheus.NewCounterFrom(
stdprometheus.CounterOpts{
Namespace: "microservices_demo",
Subsystem: "payment",
Name: "request_count",
Help: "Number of requests received.",
},
fieldKeys),
kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "microservices_demo",
Subsystem: "payment",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys),
service,
)
}
// Endpoint domain.
endpoints := MakeEndpoints(service)
handler := MakeHTTPHandler(ctx, endpoints, logger)
return handler, logger
}
func prometheusMiddleware() func(http.Handler) http.Handler {
requestDuration := prometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "walkhub",
Subsystem: "main",
Name: "request_duration_nanoseconds_count",
Help: "Total time spent serving requests.",
}, []string{
"method",
"url",
})
return func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
defer func(begin time.Time) {
requestDuration.
With("method", r.Method).
With("url", r.URL.String()).
Observe(float64(time.Since(begin)))
}(time.Now())
next.ServeHTTP(w, r)
})
}
}
func main() {
var (
debugAddr = flag.String("debug.addr", ":8080", "Debug and metrics listen address")
grpcAddr = flag.String("grpc.addr", ":8082", "gRPC (HTTP) listen address")
appdashAddr = flag.String("appdash.addr", "", "Enable Appdash tracing via an Appdash server host:port")
ircNick = flag.String("irc.nick", "gogrpctest", "IRC nickname")
ircSecret = flag.String("irc.secret", "", "IRC password")
ircHost = flag.String("irc.addr", "irc.freenode.net:6667", "IRC host system")
)
flag.Parse()
// Logging domain.
var logger log.Logger
{
logger = log.NewLogfmtLogger(os.Stdout)
logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
logger = log.NewContext(logger).With("caller", log.DefaultCaller)
}
logger.Log("msg", "hello")
defer logger.Log("msg", "goodbye")
// Metrics domain.
var cx, cxerr, joins metrics.Counter
{
// Business level metrics.
cx = prometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "relay",
Name: "connect_succeeded",
Help: "Total count of connects via the Connect method.",
}, []string{})
cxerr = prometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "relay",
Name: "connect_failed",
Help: "Total count of connect errors via the Connect method.",
}, []string{})
joins = prometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "relay",
Name: "channels_joined",
Help: "Total count of channels joined via the Join method.",
}, []string{})
}
var duration metrics.Histogram
{
// Transport level metrics.
duration = prometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "relay",
Name: "request_duration_ns",
Help: "Request duration in nanoseconds.",
}, []string{"method", "success"})
}
// Tracing domain.
var tracer stdopentracing.Tracer
{
if *appdashAddr != "" {
logger := log.NewContext(logger).With("tracer", "Appdash")
logger.Log("addr", *appdashAddr)
tracer = appdashot.NewTracer(appdash.NewRemoteCollector(*appdashAddr))
} else {
logger := log.NewContext(logger).With("tracer", "none")
logger.Log()
tracer = stdopentracing.GlobalTracer() // no-op
}
}
// Business domain.
var service relay.Service
{
service = relay.NewBasicService(*ircNick, *ircHost, *ircSecret)
service = relay.ServiceLoggingMiddleware(logger)(service)
service = relay.ServiceInstrumentingMiddleware(cx, cxerr, joins)(service)
}
// Endpoint domain.
var connectEndpoint endpoint.Endpoint
{
connectDuration := duration.With("method", "Connect")
connectLogger := log.NewContext(logger).With("method", "Connect")
connectEndpoint = relay.MakeConnectEndpoint(service)
connectEndpoint = opentracing.TraceServer(tracer, "Connect")(connectEndpoint)
connectEndpoint = relay.EndpointInstrumentingMiddleware(connectDuration)(connectEndpoint)
connectEndpoint = relay.EndpointLoggingMiddleware(connectLogger)(connectEndpoint)
}
var joinEndpoint endpoint.Endpoint
{
joinDuration := duration.With("method", "Join")
joinLogger := log.NewContext(logger).With("method", "Join")
joinEndpoint = relay.MakeJoinEndpoint(service)
joinEndpoint = opentracing.TraceServer(tracer, "Join")(joinEndpoint)
joinEndpoint = relay.EndpointInstrumentingMiddleware(joinDuration)(joinEndpoint)
joinEndpoint = relay.EndpointLoggingMiddleware(joinLogger)(joinEndpoint)
}
endpoints := relay.Endpoints{
ConnectEndpoint: connectEndpoint,
JoinEndpoint: joinEndpoint,
}
// Mechanical domain.
errc := make(chan error)
ctx := context.Background()
// Interrupt handler.
go func() {
c := make(chan os.Signal, 1)
signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
errc <- fmt.Errorf("%s", <-c)
}()
// Debug listener.
go func() {
logger := log.NewContext(logger).With("transport", "debug")
m := http.NewServeMux()
m.Handle("/debug/pprof/", http.HandlerFunc(pprof.Index))
m.Handle("/debug/pprof/cmdline", http.HandlerFunc(pprof.Cmdline))
m.Handle("/debug/pprof/profile", http.HandlerFunc(pprof.Profile))
m.Handle("/debug/pprof/symbol", http.HandlerFunc(pprof.Symbol))
m.Handle("/debug/pprof/trace", http.HandlerFunc(pprof.Trace))
m.Handle("/metrics", stdprometheus.Handler())
logger.Log("addr", *debugAddr)
errc <- http.ListenAndServe(*debugAddr, m)
}()
// gRPC transport.
go func() {
logger := log.NewContext(logger).With("transport", "gRPC")
ln, err := net.Listen("tcp", *grpcAddr)
if err != nil {
errc <- err
return
}
srv := relay.MakeGRPCServer(ctx, endpoints, tracer, logger)
s := grpc.NewServer()
pb.RegisterRelayServer(s, srv)
logger.Log("addr", *grpcAddr)
errc <- s.Serve(ln)
}()
// Run!
logger.Log("exit", <-errc)
}
func main() {
var (
addr = envString("PORT", defaultPort)
rsurl = envString("ROUTINGSERVICE_URL", defaultRoutingServiceURL)
httpAddr = flag.String("http.addr", ":"+addr, "HTTP listen address")
routingServiceURL = flag.String("service.routing", rsurl, "routing service URL")
ctx = context.Background()
)
flag.Parse()
var logger log.Logger
logger = log.NewLogfmtLogger(os.Stderr)
logger = &serializedLogger{Logger: logger}
logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
var (
cargos = repository.NewCargo()
locations = repository.NewLocation()
voyages = repository.NewVoyage()
handlingEvents = repository.NewHandlingEvent()
)
// Configure some questionable dependencies.
var (
handlingEventFactory = cargo.HandlingEventFactory{
CargoRepository: cargos,
VoyageRepository: voyages,
LocationRepository: locations,
}
handlingEventHandler = handling.NewEventHandler(
inspection.NewService(cargos, handlingEvents, nil),
)
)
// Facilitate testing by adding some cargos.
storeTestData(cargos)
fieldKeys := []string{"method"}
var rs routing.Service
rs = routing.NewProxyingMiddleware(*routingServiceURL, ctx)(rs)
var bs booking.Service
bs = booking.NewService(cargos, locations, handlingEvents, rs)
bs = booking.NewLoggingService(log.NewContext(logger).With("component", "booking"), bs)
bs = booking.NewInstrumentingService(
kitprometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "api",
Subsystem: "booking_service",
Name: "request_count",
Help: "Number of requests received.",
}, fieldKeys),
kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "api",
Subsystem: "booking_service",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys),
bs,
)
var ts tracking.Service
ts = tracking.NewService(cargos, handlingEvents)
ts = tracking.NewLoggingService(log.NewContext(logger).With("component", "tracking"), ts)
ts = tracking.NewInstrumentingService(
kitprometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "api",
Subsystem: "tracking_service",
Name: "request_count",
Help: "Number of requests received.",
}, fieldKeys),
kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "api",
Subsystem: "tracking_service",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys),
ts,
)
var hs handling.Service
hs = handling.NewService(handlingEvents, handlingEventFactory, handlingEventHandler)
hs = handling.NewLoggingService(log.NewContext(logger).With("component", "handling"), hs)
hs = handling.NewInstrumentingService(
kitprometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "api",
Subsystem: "handling_service",
Name: "request_count",
Help: "Number of requests received.",
}, fieldKeys),
kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "api",
Subsystem: "handling_service",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys),
hs,
)
httpLogger := log.NewContext(logger).With("component", "http")
mux := http.NewServeMux()
mux.Handle("/booking/v1/", booking.MakeHandler(ctx, bs, httpLogger))
mux.Handle("/tracking/v1/", tracking.MakeHandler(ctx, ts, httpLogger))
mux.Handle("/handling/v1/", handling.MakeHandler(ctx, hs, httpLogger))
http.Handle("/", accessControl(mux))
http.Handle("/metrics", stdprometheus.Handler())
errs := make(chan error, 2)
go func() {
logger.Log("transport", "http", "address", *httpAddr, "msg", "listening")
errs <- http.ListenAndServe(*httpAddr, nil)
}()
go func() {
c := make(chan os.Signal)
signal.Notify(c, syscall.SIGINT)
errs <- fmt.Errorf("%s", <-c)
}()
logger.Log("terminated", <-errs)
}
func main() {
var (
debugAddr = flag.String("debug.addr", ":8080", "Debug and metrics listen address")
httpAddr = flag.String("http.addr", ":8081", "HTTP listen address")
grpcAddr = flag.String("grpc.addr", ":8082", "gRPC (HTTP) listen address")
thriftAddr = flag.String("thrift.addr", ":8083", "Thrift listen address")
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 server 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")
)
flag.Parse()
// Logging domain.
var logger log.Logger
{
logger = log.NewLogfmtLogger(os.Stdout)
logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
logger = log.NewContext(logger).With("caller", log.DefaultCaller)
}
logger.Log("msg", "hello")
defer logger.Log("msg", "goodbye")
// Metrics domain.
var ints, chars metrics.Counter
{
// Business level metrics.
ints = prometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "addsvc",
Name: "integers_summed",
Help: "Total count of integers summed via the Sum method.",
}, []string{})
chars = prometheus.NewCounterFrom(stdprometheus.CounterOpts{
Namespace: "addsvc",
Name: "characters_concatenated",
Help: "Total count of characters concatenated via the Concat method.",
}, []string{})
}
var duration metrics.Histogram
{
// Transport level metrics.
duration = prometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "addsvc",
Name: "request_duration_ns",
Help: "Request duration in nanoseconds.",
}, []string{"method", "success"})
}
// Tracing domain.
var tracer stdopentracing.Tracer
{
if *zipkinAddr != "" {
logger := log.NewContext(logger).With("tracer", "Zipkin")
logger.Log("addr", *zipkinAddr)
collector, err := zipkin.NewKafkaCollector(
strings.Split(*zipkinAddr, ","),
zipkin.KafkaLogger(logger),
)
if err != nil {
logger.Log("err", err)
os.Exit(1)
}
tracer, err = zipkin.NewTracer(
zipkin.NewRecorder(collector, false, "localhost:80", "addsvc"),
)
if err != nil {
logger.Log("err", err)
os.Exit(1)
}
} else if *appdashAddr != "" {
logger := log.NewContext(logger).With("tracer", "Appdash")
logger.Log("addr", *appdashAddr)
tracer = appdashot.NewTracer(appdash.NewRemoteCollector(*appdashAddr))
} else if *lightstepToken != "" {
logger := log.NewContext(logger).With("tracer", "LightStep")
logger.Log() // probably don't want to print out the token :)
tracer = lightstep.NewTracer(lightstep.Options{
AccessToken: *lightstepToken,
})
defer lightstep.FlushLightStepTracer(tracer)
} else {
logger := log.NewContext(logger).With("tracer", "none")
logger.Log()
tracer = stdopentracing.GlobalTracer() // no-op
}
}
// Business domain.
var service addsvc.Service
{
service = addsvc.NewBasicService()
service = addsvc.ServiceLoggingMiddleware(logger)(service)
service = addsvc.ServiceInstrumentingMiddleware(ints, chars)(service)
}
// Endpoint domain.
var sumEndpoint endpoint.Endpoint
{
sumDuration := duration.With("method", "Sum")
sumLogger := log.NewContext(logger).With("method", "Sum")
sumEndpoint = addsvc.MakeSumEndpoint(service)
sumEndpoint = opentracing.TraceServer(tracer, "Sum")(sumEndpoint)
sumEndpoint = addsvc.EndpointInstrumentingMiddleware(sumDuration)(sumEndpoint)
sumEndpoint = addsvc.EndpointLoggingMiddleware(sumLogger)(sumEndpoint)
}
var concatEndpoint endpoint.Endpoint
{
concatDuration := duration.With("method", "Concat")
concatLogger := log.NewContext(logger).With("method", "Concat")
concatEndpoint = addsvc.MakeConcatEndpoint(service)
concatEndpoint = opentracing.TraceServer(tracer, "Concat")(concatEndpoint)
concatEndpoint = addsvc.EndpointInstrumentingMiddleware(concatDuration)(concatEndpoint)
concatEndpoint = addsvc.EndpointLoggingMiddleware(concatLogger)(concatEndpoint)
}
endpoints := addsvc.Endpoints{
SumEndpoint: sumEndpoint,
ConcatEndpoint: concatEndpoint,
}
// Mechanical domain.
errc := make(chan error)
ctx := context.Background()
// Interrupt handler.
go func() {
c := make(chan os.Signal, 1)
signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
errc <- fmt.Errorf("%s", <-c)
}()
// Debug listener.
go func() {
logger := log.NewContext(logger).With("transport", "debug")
m := http.NewServeMux()
m.Handle("/debug/pprof/", http.HandlerFunc(pprof.Index))
m.Handle("/debug/pprof/cmdline", http.HandlerFunc(pprof.Cmdline))
m.Handle("/debug/pprof/profile", http.HandlerFunc(pprof.Profile))
m.Handle("/debug/pprof/symbol", http.HandlerFunc(pprof.Symbol))
m.Handle("/debug/pprof/trace", http.HandlerFunc(pprof.Trace))
m.Handle("/metrics", stdprometheus.Handler())
logger.Log("addr", *debugAddr)
errc <- http.ListenAndServe(*debugAddr, m)
}()
// HTTP transport.
go func() {
logger := log.NewContext(logger).With("transport", "HTTP")
h := addsvc.MakeHTTPHandler(ctx, endpoints, tracer, logger)
logger.Log("addr", *httpAddr)
errc <- http.ListenAndServe(*httpAddr, h)
}()
// gRPC transport.
go func() {
logger := log.NewContext(logger).With("transport", "gRPC")
ln, err := net.Listen("tcp", *grpcAddr)
if err != nil {
errc <- err
return
}
srv := addsvc.MakeGRPCServer(ctx, endpoints, tracer, logger)
s := grpc.NewServer()
pb.RegisterAddServer(s, srv)
logger.Log("addr", *grpcAddr)
errc <- s.Serve(ln)
}()
// Thrift transport.
go func() {
logger := log.NewContext(logger).With("transport", "Thrift")
var protocolFactory thrift.TProtocolFactory
switch *thriftProtocol {
case "binary":
protocolFactory = thrift.NewTBinaryProtocolFactoryDefault()
case "compact":
protocolFactory = thrift.NewTCompactProtocolFactory()
case "json":
protocolFactory = thrift.NewTJSONProtocolFactory()
case "simplejson":
protocolFactory = thrift.NewTSimpleJSONProtocolFactory()
default:
errc <- fmt.Errorf("invalid Thrift protocol %q", *thriftProtocol)
return
}
var transportFactory thrift.TTransportFactory
if *thriftBufferSize > 0 {
transportFactory = thrift.NewTBufferedTransportFactory(*thriftBufferSize)
} else {
transportFactory = thrift.NewTTransportFactory()
}
if *thriftFramed {
transportFactory = thrift.NewTFramedTransportFactory(transportFactory)
}
transport, err := thrift.NewTServerSocket(*thriftAddr)
if err != nil {
errc <- err
return
}
logger.Log("addr", *thriftAddr)
errc <- thrift.NewTSimpleServer4(
thriftadd.NewAddServiceProcessor(addsvc.MakeThriftHandler(ctx, endpoints)),
transport,
transportFactory,
protocolFactory,
).Serve()
}()
// Run!
logger.Log("exit", <-errc)
}
func main() {
flag.Parse()
// Mechanical stuff.
errc := make(chan error)
ctx := context.Background()
// Log domain.
var logger log.Logger
{
logger = log.NewLogfmtLogger(os.Stderr)
logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
logger = log.NewContext(logger).With("caller", log.DefaultCaller)
}
dbconn := false
for !dbconn {
err := db.Init()
if err != nil {
if err == db.ErrNoDatabaseSelected {
corelog.Fatal(err)
}
corelog.Print(err)
} else {
dbconn = true
}
}
fieldKeys := []string{"method"}
// Service domain.
var service api.Service
{
service = api.NewFixedService()
service = api.LoggingMiddleware(logger)(service)
service = api.NewInstrumentingService(
kitprometheus.NewCounterFrom(
stdprometheus.CounterOpts{
Namespace: "microservices_demo",
Subsystem: "user",
Name: "request_count",
Help: "Number of requests received.",
},
fieldKeys),
kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "microservices_demo",
Subsystem: "user",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys),
service,
)
}
// Endpoint domain.
endpoints := api.MakeEndpoints(service)
// Create and launch the HTTP server.
go func() {
logger.Log("transport", "HTTP", "port", port)
handler := api.MakeHTTPHandler(ctx, endpoints, logger)
errc <- http.ListenAndServe(fmt.Sprintf(":%v", port), handler)
}()
// Capture interrupts.
go func() {
c := make(chan os.Signal)
signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
errc <- fmt.Errorf("%s", <-c)
}()
logger.Log("exit", <-errc)
}
func main() {
var (
port = flag.String("port", "8081", "Port to bind HTTP listener") // TODO(pb): should be -addr, default ":8081"
images = flag.String("images", "./images/", "Image path")
dsn = flag.String("DSN", "catalogue_user:default_password@tcp(catalogue-db:3306)/socksdb", "Data Source Name: [username[:password]@][protocol[(address)]]/dbname")
)
flag.Parse()
fmt.Fprintf(os.Stderr, "images: %q\n", *images)
abs, err := filepath.Abs(*images)
fmt.Fprintf(os.Stderr, "Abs(images): %q (%v)\n", abs, err)
pwd, err := os.Getwd()
fmt.Fprintf(os.Stderr, "Getwd: %q (%v)\n", pwd, err)
files, _ := filepath.Glob(*images + "/*")
fmt.Fprintf(os.Stderr, "ls: %q\n", files) // contains a list of all files in the current directory
// Mechanical stuff.
errc := make(chan error)
ctx := context.Background()
// Log domain.
var logger log.Logger
{
logger = log.NewLogfmtLogger(os.Stderr)
logger = log.NewContext(logger).With("ts", log.DefaultTimestampUTC)
logger = log.NewContext(logger).With("caller", log.DefaultCaller)
}
// Data domain.
db, err := sqlx.Open("mysql", *dsn)
if err != nil {
logger.Log("err", err)
os.Exit(1)
}
defer db.Close()
// Check if DB connection can be made, only for logging purposes, should not fail/exit
err = db.Ping()
if err != nil {
logger.Log("Error", "Unable to connect to Database", "DSN", dsn)
}
fieldKeys := []string{"method"}
// Service domain.
var service catalogue.Service
{
service = catalogue.NewCatalogueService(db, logger)
service = catalogue.LoggingMiddleware(logger)(service)
service = catalogue.NewInstrumentingService(
kitprometheus.NewCounterFrom(
stdprometheus.CounterOpts{
Namespace: "microservices_demo",
Subsystem: "catalogue",
Name: "request_count",
Help: "Number of requests received.",
},
fieldKeys),
kitprometheus.NewSummaryFrom(stdprometheus.SummaryOpts{
Namespace: "microservices_demo",
Subsystem: "catalogue",
Name: "request_latency_microseconds",
Help: "Total duration of requests in microseconds.",
}, fieldKeys),
service,
)
}
// Endpoint domain.
endpoints := catalogue.MakeEndpoints(service)
// Create and launch the HTTP server.
go func() {
logger.Log("transport", "HTTP", "port", *port)
handler := catalogue.MakeHTTPHandler(ctx, endpoints, *images, logger)
errc <- http.ListenAndServe(":"+*port, handler)
}()
// Capture interrupts.
go func() {
c := make(chan os.Signal)
signal.Notify(c, syscall.SIGINT, syscall.SIGTERM)
errc <- fmt.Errorf("%s", <-c)
}()
logger.Log("exit", <-errc)
}