// NewMetricsExpvar initializes and returns a Metrics exposed over the expvar system.
func NewMetricsExpvar() Metrics {
return Metrics{
RequestCount: expvar.NewCounter("request_count"),
ResponseTime: metrics.NewTimeHistogram(
time.Microsecond,
expvar.NewHistogram("response_time", 0, int64(time.Second), sigfigs, quantiles...),
),
Uploads: expvar.NewCounter("uploads"),
UploadErrors: expvar.NewCounter("upload_errors"),
}
}
func main() {
logger := log.NewLogfmtLogger(os.Stdout)
ctx := context.Background()
c := &countService{}
var svc endpoint.Endpoint
svc = makeAddEndpoint(c)
limit := ratelimit.NewBucket(2*time.Second, 1)
svc = kitratelimit.NewTokenBucketLimiter(limit)(svc)
requestCount := expvar.NewCounter("request.count")
svc = metricsMiddleware(requestCount)(svc)
svc = loggingMiddlware(logger)(svc)
addHandler := httptransport.NewServer(
ctx,
svc,
decodeAddRequest,
encodeResponse,
httptransport.ServerBefore(beforeIDExtractor, beforePATHExtractor),
)
http.Handle("/add", addHandler)
port := os.Getenv("PORT")
logger.Log("listening on", port)
if err := http.ListenAndServe(":"+port, nil); err != nil {
logger.Log("listen.error", err)
}
}
func TestMultiWith(t *testing.T) {
c := metrics.NewMultiCounter(
"multifoo",
expvar.NewCounter("foo"),
prometheus.NewCounter(stdprometheus.CounterOpts{
Namespace: "test",
Subsystem: "multi_with",
Name: "bar",
Help: "Bar counter.",
}, []string{"a"}),
)
c.Add(1)
c.With(metrics.Field{Key: "a", Value: "1"}).Add(2)
c.Add(3)
if want, have := strings.Join([]string{
`# HELP test_multi_with_bar Bar counter.`,
`# TYPE test_multi_with_bar counter`,
`test_multi_with_bar{a="1"} 2`,
`test_multi_with_bar{a="unknown"} 4`,
}, "\n"), scrapePrometheus(t); !strings.Contains(have, want) {
t.Errorf("Prometheus metric stanza not found or incorrect\n%s", have)
}
}
func TestCounter(t *testing.T) {
var (
name = "m"
value = 123
)
expvar.NewCounter(name).With(metrics.Field{Key: "ignored", Value: "field"}).Add(uint64(value))
if want, have := fmt.Sprint(value), stdexpvar.Get(name).String(); want != have {
t.Errorf("want %q, have %q", want, have)
}
}
func TestMultiCounter(t *testing.T) {
metrics.NewMultiCounter(
expvar.NewCounter("alpha"),
prometheus.NewCounter(stdprometheus.CounterOpts{
Namespace: "test",
Subsystem: "multi_counter",
Name: "beta",
Help: "Beta counter.",
}, []string{"a"}),
).With(metrics.Field{Key: "a", Value: "b"}).Add(123)
if want, have := "123", stdexpvar.Get("alpha").String(); want != have {
t.Errorf("expvar: want %q, have %q", want, have)
}
if want, have := strings.Join([]string{
`# HELP test_multi_counter_beta Beta counter.`,
`# TYPE test_multi_counter_beta counter`,
`test_multi_counter_beta{a="b"} 123`,
}, "\n"), scrapePrometheus(t); !strings.Contains(have, want) {
t.Errorf("Prometheus metric stanza not found or incorrect\n%s", have)
}
}
func makeInstrumentation(namespace, name, helpCounter, helpDuration string) (metrics.Counter, metrics.TimeHistogram) {
counter := metrics.NewMultiCounter(
expvar.NewCounter(fmt.Sprintf("requests_%s", name)),
statsd.NewCounter(ioutil.Discard, fmt.Sprintf("requests_%s_total", name), time.Second),
prometheus.NewCounter(stdprometheus.CounterOpts{
Namespace: namespace,
Subsystem: name,
Name: "requests_total",
Help: helpCounter,
}, []string{}),
)
duration := metrics.NewTimeHistogram(time.Nanosecond, metrics.NewMultiHistogram(
expvar.NewHistogram(fmt.Sprintf("duration_%s_nanoseconds_total", name), 0, 1e9, 3, 50, 95, 99),
statsd.NewHistogram(ioutil.Discard, fmt.Sprintf("duration_%s_nanoseconds_total", name), time.Second),
prometheus.NewSummary(stdprometheus.SummaryOpts{
Namespace: namespace,
Subsystem: name,
Name: "duration_nanoseconds_total",
Help: helpDuration,
}, []string{}),
))
return counter, duration
}
func main() {
// Flag domain. Note that gRPC transitively registers flags via its import
// of glog. So, we define a new flag set, to keep those domains distinct.
fs := flag.NewFlagSet("", flag.ExitOnError)
var (
debugAddr = fs.String("debug.addr", ":8000", "Address for HTTP debug/instrumentation server")
httpAddr = fs.String("http.addr", ":8001", "Address for HTTP (JSON) server")
netrpcAddr = fs.String("netrpc.addr", ":8003", "Address for net/rpc server")
proxyHTTPAddr = fs.String("proxy.http.url", "", "if set, proxy requests over HTTP to this addsvc")
zipkinServiceName = fs.String("zipkin.service.name", "addsvc", "Zipkin service name")
zipkinCollectorAddr = fs.String("zipkin.collector.addr", "", "Zipkin Scribe collector address (empty will log spans)")
zipkinCollectorTimeout = fs.Duration("zipkin.collector.timeout", time.Second, "Zipkin collector timeout")
zipkinCollectorBatchSize = fs.Int("zipkin.collector.batch.size", 100, "Zipkin collector batch size")
zipkinCollectorBatchInterval = fs.Duration("zipkin.collector.batch.interval", time.Second, "Zipkin collector batch interval")
)
flag.Usage = fs.Usage // only show our flags
fs.Parse(os.Args[1:])
// `package log` domain
var logger kitlog.Logger
logger = kitlog.NewLogfmtLogger(os.Stderr)
logger = kitlog.NewContext(logger).With("ts", kitlog.DefaultTimestampUTC)
stdlog.SetOutput(kitlog.NewStdlibAdapter(logger)) // redirect stdlib logging to us
stdlog.SetFlags(0) // flags are handled in our logger
// `package metrics` domain
requests := metrics.NewMultiCounter(
expvar.NewCounter("requests"),
statsd.NewCounter(ioutil.Discard, "requests_total", time.Second),
prometheus.NewCounter(stdprometheus.CounterOpts{
Namespace: "addsvc",
Subsystem: "add",
Name: "requests_total",
Help: "Total number of received requests.",
}, []string{}),
)
duration := metrics.NewTimeHistogram(time.Nanosecond, metrics.NewMultiHistogram(
expvar.NewHistogram("duration_nanoseconds_total", 0, 1e9, 3, 50, 95, 99),
statsd.NewHistogram(ioutil.Discard, "duration_nanoseconds_total", time.Second),
prometheus.NewSummary(stdprometheus.SummaryOpts{
Namespace: "addsvc",
Subsystem: "add",
Name: "duration_nanoseconds_total",
Help: "Total nanoseconds spend serving requests.",
}, []string{}),
))
_, _ = requests, duration
// `package tracing` domain
zipkinHostPort := "localhost:1234" // TODO Zipkin makes overly simple assumptions about services
var zipkinCollector zipkin.Collector = loggingCollector{logger}
if *zipkinCollectorAddr != "" {
var err error
if zipkinCollector, err = zipkin.NewScribeCollector(
*zipkinCollectorAddr,
*zipkinCollectorTimeout,
zipkin.ScribeBatchSize(*zipkinCollectorBatchSize),
zipkin.ScribeBatchInterval(*zipkinCollectorBatchInterval),
zipkin.ScribeLogger(logger),
); err != nil {
logger.Log("err", err)
os.Exit(1)
}
}
zipkinMethodName := "add"
zipkinSpanFunc := zipkin.MakeNewSpanFunc(zipkinHostPort, *zipkinServiceName, zipkinMethodName)
// Our business and operational domain
var a add.Adder = pureAdd{}
if *proxyHTTPAddr != "" {
var e endpoint.Endpoint
e = add.NewAdderAddHTTPClient("GET", *proxyHTTPAddr, zipkin.ToRequest(zipkinSpanFunc))
e = zipkin.AnnotateClient(zipkinSpanFunc, zipkinCollector)(e)
a = add.MakeAdderClient(func(method string) endpoint.Endpoint {
if method != "Add" {
panic(fmt.Errorf("unknown method %s", method))
}
return e
})
}
// This could happen at endpoint level.
// a = logging(logger)(a)
// a = instrument(requests, duration)(a)
// Server domain
var e endpoint.Endpoint
e = add.MakeAdderEndpoints(a).Add
e = zipkin.AnnotateServer(zipkinSpanFunc, zipkinCollector)(e)
// Mechanical stuff
rand.Seed(time.Now().UnixNano())
root := context.Background()
errc := make(chan error)
go func() {
errc <- interrupt()
}()
// Transport: HTTP (debug/instrumentation)
go func() {
logger.Log("addr", *debugAddr, "transport", "debug")
errc <- http.ListenAndServe(*debugAddr, nil)
}()
// Transport: HTTP (JSON)
go func() {
ctx, cancel := context.WithCancel(root)
defer cancel()
before := []httptransport.RequestFunc{zipkin.ToContext(zipkinSpanFunc, logger)}
after := []httptransport.ResponseFunc{}
handler := add.MakeAdderAddHTTPBinding(ctx, e, before, after)
logger.Log("addr", *httpAddr, "transport", "HTTP/JSON")
errc <- http.ListenAndServe(*httpAddr, handler)
}()
// Transport: net/rpc
go func() {
ctx, cancel := context.WithCancel(root)
defer cancel()
s := rpc.NewServer()
s.RegisterName("Add", add.AdderAddNetrpcBinding{ctx, e})
s.HandleHTTP(rpc.DefaultRPCPath, rpc.DefaultDebugPath)
logger.Log("addr", *netrpcAddr, "transport", "net/rpc")
errc <- http.ListenAndServe(*netrpcAddr, s)
}()
logger.Log("fatal", <-errc)
}
func main() {
// Flag domain. Note that gRPC transitively registers flags via its import
// of glog. So, we define a new flag set, to keep those domains distinct.
fs := flag.NewFlagSet("", flag.ExitOnError)
var (
debugAddr = fs.String("debug.addr", ":8000", "Address for HTTP debug/instrumentation server")
httpAddr = fs.String("http.addr", ":8001", "Address for HTTP (JSON) server")
grpcAddr = fs.String("grpc.addr", ":8002", "Address for gRPC server")
netrpcAddr = fs.String("netrpc.addr", ":8003", "Address for net/rpc server")
thriftAddr = fs.String("thrift.addr", ":8004", "Address for Thrift server")
thriftProtocol = fs.String("thrift.protocol", "binary", "binary, compact, json, simplejson")
thriftBufferSize = fs.Int("thrift.buffer.size", 0, "0 for unbuffered")
thriftFramed = fs.Bool("thrift.framed", false, "true to enable framing")
proxyHTTPAddr = fs.String("proxy.http.url", "", "if set, proxy requests over HTTP to this addsvc")
zipkinServiceName = fs.String("zipkin.service.name", "addsvc", "Zipkin service name")
zipkinCollectorAddr = fs.String("zipkin.collector.addr", "", "Zipkin Scribe collector address (empty will log spans)")
zipkinCollectorTimeout = fs.Duration("zipkin.collector.timeout", time.Second, "Zipkin collector timeout")
zipkinCollectorBatchSize = fs.Int("zipkin.collector.batch.size", 100, "Zipkin collector batch size")
zipkinCollectorBatchInterval = fs.Duration("zipkin.collector.batch.interval", time.Second, "Zipkin collector batch interval")
)
flag.Usage = fs.Usage // only show our flags
fs.Parse(os.Args[1:])
// `package log` domain
var logger kitlog.Logger
logger = kitlog.NewLogfmtLogger(os.Stderr)
logger = kitlog.With(logger, "ts", kitlog.DefaultTimestampUTC)
stdlog.SetOutput(kitlog.NewStdlibAdapter(logger)) // redirect stdlib logging to us
stdlog.SetFlags(0) // flags are handled in our logger
// `package metrics` domain
requests := metrics.NewMultiCounter(
expvar.NewCounter("requests"),
statsd.NewCounter(ioutil.Discard, "requests_total", time.Second),
prometheus.NewCounter(stdprometheus.CounterOpts{
Namespace: "addsvc",
Subsystem: "add",
Name: "requests_total",
Help: "Total number of received requests.",
}, []string{}),
)
duration := metrics.NewTimeHistogram(time.Nanosecond, metrics.NewMultiHistogram(
expvar.NewHistogram("duration_nanoseconds_total", 0, 1e9, 3, 50, 95, 99),
statsd.NewHistogram(ioutil.Discard, "duration_nanoseconds_total", time.Second),
prometheus.NewSummary(stdprometheus.SummaryOpts{
Namespace: "addsvc",
Subsystem: "add",
Name: "duration_nanoseconds_total",
Help: "Total nanoseconds spend serving requests.",
}, []string{}),
))
// `package tracing` domain
zipkinHostPort := "localhost:1234" // TODO Zipkin makes overly simple assumptions about services
var zipkinCollector zipkin.Collector = loggingCollector{logger}
if *zipkinCollectorAddr != "" {
var err error
if zipkinCollector, err = zipkin.NewScribeCollector(
*zipkinCollectorAddr,
*zipkinCollectorTimeout,
*zipkinCollectorBatchSize,
*zipkinCollectorBatchInterval,
); err != nil {
logger.Log("err", err)
os.Exit(1)
}
}
zipkinMethodName := "add"
zipkinSpanFunc := zipkin.MakeNewSpanFunc(zipkinHostPort, *zipkinServiceName, zipkinMethodName)
zipkin.Log.Swap(logger) // log diagnostic/error details
// Our business and operational domain
var a Add = pureAdd
if *proxyHTTPAddr != "" {
var e endpoint.Endpoint
e = httpclient.NewClient("GET", *proxyHTTPAddr, zipkin.ToRequest(zipkinSpanFunc))
e = zipkin.AnnotateClient(zipkinSpanFunc, zipkinCollector)(e)
a = proxyAdd(e, logger)
}
a = logging(logger)(a)
a = instrument(requests, duration)(a)
// Server domain
var e endpoint.Endpoint
e = makeEndpoint(a)
e = zipkin.AnnotateServer(zipkinSpanFunc, zipkinCollector)(e)
// Mechanical stuff
rand.Seed(time.Now().UnixNano())
root := context.Background()
errc := make(chan error)
go func() {
errc <- interrupt()
}()
// Transport: HTTP (debug/instrumentation)
go func() {
logger.Log("addr", *debugAddr, "transport", "debug")
errc <- http.ListenAndServe(*debugAddr, nil)
}()
// Transport: HTTP (JSON)
go func() {
ctx, cancel := context.WithCancel(root)
defer cancel()
before := []httptransport.BeforeFunc{zipkin.ToContext(zipkinSpanFunc)}
after := []httptransport.AfterFunc{}
handler := makeHTTPBinding(ctx, e, before, after)
logger.Log("addr", *httpAddr, "transport", "HTTP/JSON")
errc <- http.ListenAndServe(*httpAddr, handler)
}()
// Transport: gRPC
go func() {
ln, err := net.Listen("tcp", *grpcAddr)
if err != nil {
errc <- err
return
}
s := grpc.NewServer() // uses its own context?
pb.RegisterAddServer(s, grpcBinding{e})
logger.Log("addr", *grpcAddr, "transport", "gRPC")
errc <- s.Serve(ln)
}()
// Transport: net/rpc
go func() {
ctx, cancel := context.WithCancel(root)
defer cancel()
s := rpc.NewServer()
s.RegisterName("addsvc", NetrpcBinding{ctx, e})
s.HandleHTTP(rpc.DefaultRPCPath, rpc.DefaultDebugPath)
logger.Log("addr", *netrpcAddr, "transport", "net/rpc")
errc <- http.ListenAndServe(*netrpcAddr, s)
}()
// Transport: Thrift
go func() {
ctx, cancel := context.WithCancel(root)
defer cancel()
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, "transport", "Thrift")
errc <- thrift.NewTSimpleServer4(
thriftadd.NewAddServiceProcessor(thriftBinding{ctx, e}),
transport,
transportFactory,
protocolFactory,
).Serve()
}()
logger.Log("fatal", <-errc)
}
// NewCounter implements Provider.
func (p expvarProvider) NewCounter(name string) metrics.Counter {
return expvar.NewCounter(name)
}