ppkratos

ppkratos

This package instruments the go-kratos/kratos/v2 package.

Installation

$ go get github.com/pinpoint-apm/pinpoint-go-agent/plugin/kratos

import "github.com/pinpoint-apm/pinpoint-go-agent/plugin/kratos"

Usage

This package instruments kratos servers and clients.

server

To instrument a kratos server, use ServerMiddleware.

httpSrv := http.NewServer(
    http.Address(":8000"),
    http.Middleware(ppkratos.ServerMiddleware()),
)

The server middleware adds the pinpoint.Tracer to the kratos server handler's context. By using the pinpoint.FromContext function, this tracer can be obtained. Alternatively, the context of the handler may be propagated where the context that contains the pinpoint.Tracer is required.

func (s *server) SayHello(ctx context.Context, in *helloworld.HelloRequest) (*helloworld.HelloReply, error) {
    tracer := pinpoint.FromContext(ctx)
    defer tracer.NewSpanEvent("f1").EndSpanEvent()
    ...
}

package main

import (
    "github.com/go-kratos/kratos/v2"
    "github.com/go-kratos/kratos/v2/transport"
    "github.com/go-kratos/kratos/v2/transport/http"
    "github.com/pinpoint-apm/pinpoint-go-agent"
    "github.com/pinpoint-apm/pinpoint-go-agent/plugin/kratos"
)

type server struct {
    helloworld.UnimplementedGreeterServer
}

func (s *server) SayHello(ctx context.Context, in *helloworld.HelloRequest) (*helloworld.HelloReply, error) {
    tracer := pinpoint.FromContext(ctx)
    defer tracer.NewSpanEvent("f1").EndSpanEvent()

    return &helloworld.HelloReply{Message: fmt.Sprintf("Hello %+v", in.Name)}, nil
}

func main() {
    ... //setup agent
	
    s := &server{}
    httpSrv := http.NewServer(
        http.Address(":8000"),
        http.Middleware(
            ppkratos.ServerMiddleware(),
        ),
    )
    ...
}

Full Example Source

client

To instrument a kratos client, use ClientMiddleware.

conn, err := transhttp.NewClient(
    context.Background(),
    transhttp.WithMiddleware(ppkratos.ClientMiddleware()),
    transhttp.WithEndpoint("127.0.0.1:8000"),
)

It is necessary to pass the context containing the pinpoint.Tracer to kratos client.

client := pb.NewGreeterHTTPClient(conn)
reply, err := client.SayHello(pinpoint.NewContext(context.Background(), tracer), &pb.HelloRequest{Name: "kratos"})

import (
    transhttp "github.com/go-kratos/kratos/v2/transport/http"
    "github.com/pinpoint-apm/pinpoint-go-agent"
    "github.com/pinpoint-apm/pinpoint-go-agent/plugin/kratos"
)

func callHTTP(w http.ResponseWriter, r *http.Request) {
    conn, err := transhttp.NewClient(
        context.Background(),
        transhttp.WithMiddleware(ppkratos.ClientMiddleware()),
        transhttp.WithEndpoint("127.0.0.1:8000"),
    )

    client := pb.NewGreeterHTTPClient(conn)
    reply, err := client.SayHello(r.Context(), &pb.HelloRequest{Name: "kratos"})
    ...
}

Full Example Source