micro/server/server_context.go
2015-05-05 19:05:06 +01:00

121 lines
3.2 KiB
Go

package server
import (
"net/http"
"sync"
log "github.com/golang/glog"
"github.com/myodc/go-micro/client"
)
var ctxs = struct {
sync.Mutex
m map[*http.Request]*serverContext
}{
m: make(map[*http.Request]*serverContext),
}
// A server context interface
type Context interface {
Request() Request // the request made to the server
Headers() Headers // the response headers
NewRequest(string, string, interface{}) client.Request // a new scoped client request
NewProtoRequest(string, string, interface{}) client.Request // a new scoped client request
NewJsonRequest(string, string, interface{}) client.Request // a new scoped client request
}
// context represents the context of an in-flight HTTP request.
// It implements the appengine.Context and http.ResponseWriter interfaces.
type serverContext struct {
req *serverRequest
outCode int
outHeader http.Header
outBody []byte
}
// Copied from $GOROOT/src/pkg/net/http/transfer.go. Some response status
// codes do not permit a response body (nor response entity headers such as
// Content-Length, Content-Type, etc).
func bodyAllowedForStatus(status int) bool {
switch {
case status >= 100 && status <= 199:
return false
case status == 204:
return false
case status == 304:
return false
}
return true
}
func getServerContext(req *http.Request) *serverContext {
ctxs.Lock()
c := ctxs.m[req]
ctxs.Unlock()
if c == nil {
// Someone passed in an http.Request that is not in-flight.
panic("NewContext passed an unknown http.Request")
}
return c
}
func (c *serverContext) NewRequest(service, method string, request interface{}) client.Request {
req := client.NewRequest(service, method, request)
// TODO: set headers and scope
req.Headers().Set("X-User-Session", c.Request().Session("X-User-Session"))
return req
}
func (c *serverContext) NewProtoRequest(service, method string, request interface{}) client.Request {
req := client.NewProtoRequest(service, method, request)
// TODO: set headers and scope
req.Headers().Set("X-User-Session", c.Request().Session("X-User-Session"))
return req
}
func (c *serverContext) NewJsonRequest(service, method string, request interface{}) client.Request {
req := client.NewJsonRequest(service, method, request)
// TODO: set headers and scope
req.Headers().Set("X-User-Session", c.Request().Session("X-User-Session"))
return req
}
// The response headers
func (c *serverContext) Headers() Headers {
return c.outHeader
}
// The response headers
func (c *serverContext) Header() http.Header {
return c.outHeader
}
// The request made to the server
func (c *serverContext) Request() Request {
return c.req
}
func (c *serverContext) Write(b []byte) (int, error) {
if c.outCode == 0 {
c.WriteHeader(http.StatusOK)
}
if len(b) > 0 && !bodyAllowedForStatus(c.outCode) {
return 0, http.ErrBodyNotAllowed
}
c.outBody = append(c.outBody, b...)
return len(b), nil
}
func (c *serverContext) WriteHeader(code int) {
if c.outCode != 0 {
log.Error("WriteHeader called multiple times on request.")
return
}
c.outCode = code
}
func GetContext(r *http.Request) *serverContext {
return getServerContext(r)
}