看來(lái)您可以將某些東西偷偷放入自定義編解碼器中，以將小寫(xiě)方法定向到正確的大寫(xiě)方法。編寫(xiě) gorilla/rpc/json 實(shí)現(xiàn)的 CodecRequest，您可以繼續(xù)使用所有 gorilla 機(jī)器來(lái)處理請(qǐng)求。
下面的工作示例?？雌饋?lái)很長(zhǎng)，但都是評(píng)論。
package main
import (
"fmt"
"log"
"net/http"
"strings"
"unicode"
"unicode/utf8"
"github.com/gorilla/mux"
"github.com/gorilla/rpc"
"github.com/gorilla/rpc/json"
)
type Args struct {
A, B int
}
type Arith int
type Result int
func (t *Arith) Multiply(r *http.Request, args *Args, result *Result) error {
log.Printf("Multiplying %d with %d\n", args.A, args.B)
*result = Result(args.A * args.B)
return nil
}
// UpCodec creates a CodecRequest to process each request.
type UpCodec struct {
}
// NewUpCodec returns a new UpCodec.
func NewUpCodec() *UpCodec {
return &UpCodec{}
}
// NewRequest returns a new CodecRequest of type UpCodecRequest.
func (c *UpCodec) NewRequest(r *http.Request) rpc.CodecRequest {
outerCR := &UpCodecRequest{} // Our custom CR
jsonC := json.NewCodec() // json Codec to create json CR
innerCR := jsonC.NewRequest(r) // create the json CR, sort of.
// NOTE - innerCR is of the interface type rpc.CodecRequest.
// Because innerCR is of the rpc.CR interface type, we need a
// type assertion in order to assign it to our struct field's type.
// We defined the source of the interface implementation here, so
// we can be confident that innerCR will be of the correct underlying type
outerCR.CodecRequest = innerCR.(*json.CodecRequest)
return outerCR
}
// UpCodecRequest decodes and encodes a single request. UpCodecRequest
// implements gorilla/rpc.CodecRequest interface primarily by embedding
// the CodecRequest from gorilla/rpc/json. By selectively adding
// CodecRequest methods to UpCodecRequest, we can modify that behaviour
// while maintaining all the other remaining CodecRequest methods from
// gorilla's rpc/json implementation
type UpCodecRequest struct {
*json.CodecRequest
}
// Method returns the decoded method as a string of the form "Service.Method"
// after checking for, and correcting a lowercase method name
// By being of lower depth in the struct , Method will replace the implementation
// of Method() on the embedded CodecRequest. Because the request data is part
// of the embedded json.CodecRequest, and unexported, we have to get the
// requested method name via the embedded CR's own method Method().
// Essentially, this just intercepts the return value from the embedded
// gorilla/rpc/json.CodecRequest.Method(), checks/modifies it, and passes it
// on to the calling rpc server.
func (c *UpCodecRequest) Method() (string, error) {
m, err := c.CodecRequest.Method()
if len(m) > 1 && err == nil {
parts := strings.Split(m, ".")
service, method := parts[0], parts[1]
r, n := utf8.DecodeRuneInString(method) // get the first rune, and it's length
if unicode.IsLower(r) {
upMethod := service + "." + string(unicode.ToUpper(r)) + method[n:]
log.Printf("lowercase method %s requested: treated as %s\n", m, upMethod)
return upMethod, err
}
}
return m, err
}
func main() {
s := rpc.NewServer()
// Register our own Codec
s.RegisterCodec(NewUpCodec(), "application/json")
s.RegisterCodec(NewUpCodec(), "application/json;charset=UTF-8")
arith := new(Arith)
s.RegisterService(arith, "")
r := mux.NewRouter()
r.Handle("/rpc", s)
fmt.Println(http.ListenAndServe(":1234", r))
}
通過(guò)以下方式調(diào)用方法：
curl -X POST -H "Content-Type: application/json" -d '{"id": 1, "method": "Arith.multiply", "params": [{"A": 10, "B": 30}]}' 127.0.0.1:1234/rpc
