httprpc - httprpc.go

     1  // Package httprpc creates an HTTP POST endpoint that wraps an RPC server
     2  package httprpc // import "vimagination.zapto.org/httprpc"
     3  
     4  import (
     5  	"io"
     6  	"net/http"
     7  	"net/rpc"
     8  )
     9  
    10  type httpRPC struct {
    11  	server      *rpc.Server
    12  	serverCodec func(io.ReadWriteCloser) rpc.ServerCodec
    13  	readLimit   int64
    14  	contentType string
    15  }
    16  
    17  // Handle returns a new http.Handler that wraps an RPC server
    18  func Handle(server *rpc.Server, serverCodec func(io.ReadWriteCloser) rpc.ServerCodec, readLimit int64, contentType string) http.Handler {
    19  	if server == nil {
    20  		server = rpc.DefaultServer
    21  	}
    22  	return httpRPC{
    23  		server:      server,
    24  		serverCodec: serverCodec,
    25  		readLimit:   readLimit,
    26  		contentType: contentType,
    27  	}
    28  }
    29  
    30  type conn struct {
    31  	io.Reader
    32  	io.Closer
    33  	io.Writer
    34  }
    35  
    36  func (h httpRPC) ServeHTTP(w http.ResponseWriter, r *http.Request) {
    37  	if h.contentType != "" {
    38  		w.Header().Set("Content-Type", h.contentType)
    39  	}
    40  	c := conn{
    41  		Reader: r.Body,
    42  		Closer: r.Body,
    43  		Writer: w,
    44  	}
    45  	if h.readLimit > 0 {
    46  		c.Reader = io.LimitReader(r.Body, h.readLimit)
    47  	}
    48  	h.server.ServeCodec(h.serverCodec(&c))
    49  }