micro/examples/client/main.go
2015-11-27 00:17:36 +00:00

155 lines
3.3 KiB
Go

package main
import (
"fmt"
"time"
"github.com/micro/go-micro/client"
"github.com/micro/go-micro/cmd"
"github.com/micro/go-micro/codec/pb"
c "github.com/micro/go-micro/context"
example "github.com/micro/go-micro/examples/server/proto/example"
"golang.org/x/net/context"
)
// wrapper example code
// log wrapper logs every time a request is made
type logWrapper struct {
client.Client
}
func (l *logWrapper) Call(ctx context.Context, req client.Request, rsp interface{}) error {
md, _ := c.GetMetadata(ctx)
fmt.Printf("[Log Wrapper] ctx: %v service: %s method: %s\n", md, req.Service(), req.Method())
return l.Client.Call(ctx, req, rsp)
}
// trace wrapper attaches a unique trace ID - timestamp
type traceWrapper struct {
client.Client
}
func (t *traceWrapper) Call(ctx context.Context, req client.Request, rsp interface{}) error {
ctx = c.WithMetadata(ctx, map[string]string{
"X-Trace-Id": fmt.Sprintf("%d", time.Now().Unix()),
})
return t.Client.Call(ctx, req, rsp)
}
// Implements client.Wrapper as logWrapper
func logWrap(c client.Client) client.Client {
return &logWrapper{c}
}
// Implements client.Wrapper as traceWrapper
func traceWrap(c client.Client) client.Client {
return &traceWrapper{c}
}
// publishes a message
func pub() {
msg := client.NewPublication("topic.go.micro.srv.example", &example.Message{
Say: "This is a publication",
})
// create context with metadata
ctx := c.WithMetadata(context.Background(), map[string]string{
"X-User-Id": "john",
"X-From-Id": "script",
})
// publish message
if err := client.Publish(ctx, msg); err != nil {
fmt.Println("pub err: ", err)
return
}
fmt.Printf("Published: %v\n", msg)
}
func call(i int) {
// Create new request to service go.micro.srv.example, method Example.Call
req := client.NewRequest("go.micro.srv.example", "Example.Call", &example.Request{
Name: "John",
})
// create context with metadata
ctx := c.WithMetadata(context.Background(), map[string]string{
"X-User-Id": "john",
"X-From-Id": "script",
})
rsp := &example.Response{}
// Call service
if err := client.Call(ctx, req, rsp); err != nil {
fmt.Println("call err: ", err, rsp)
return
}
fmt.Println("Call:", i, "rsp:", rsp.Msg)
}
func stream() {
// Create new request to service go.micro.srv.example, method Example.Call
req := client.NewRequest("go.micro.srv.example", "Example.Stream", &example.StreamingRequest{
Count: int64(10),
})
rspChan := make(chan *example.StreamingResponse, 10)
stream, err := client.Stream(context.Background(), req, rspChan)
if err != nil {
fmt.Println("err:", err)
return
}
for rsp := range rspChan {
fmt.Println("Stream: rsp:", rsp.Count)
}
if stream.Error() != nil {
fmt.Println("stream err:", err)
return
}
stream.Close()
}
func main() {
cmd.Init()
client.DefaultClient = client.NewClient(
client.Codec("application/pb", pb.Codec),
client.ContentType("application/pb"),
)
fmt.Println("\n--- Call example ---\n")
for i := 0; i < 10; i++ {
call(i)
}
fmt.Println("\n--- Streamer example ---\n")
stream()
fmt.Println("\n--- Publisher example ---\n")
pub()
fmt.Println("\n--- Wrapper example ---\n")
// Wrap the default client
client.DefaultClient = logWrap(client.DefaultClient)
call(0)
// Wrap using client.Wrap option
client.DefaultClient = client.NewClient(
client.Wrap(traceWrap),
client.Wrap(logWrap),
)
call(1)
}