jhttp: clean up leftover code

After #82 removed support for parameter injection, support for plumbing the
HTTP request context into the client became pointless. This change removes the
vestiges of it, which can no longer serve any useful purpose.

jhttp/bridge.go

@@ -5,7 +5,6 @@
 package jhttp
 
 import (
-	"context"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -34,10 +33,6 @@ import (
 // If the request completes, whether or not there is an error, the HTTP
 // response is 200 (OK) for ordinary requests or 204 (No Response) for
 // notifications, and the response body contains the JSON-RPC response.
-//
-// The bridge attaches the inbound HTTP request to the context passed to the
-// client, allowing an EncodeContext callback to retrieve state from the HTTP
-// headers. Use jhttp.HTTPRequest to retrieve the request from the context.
 type Bridge struct {
 	local    server.Local
 	parseReq func(*http.Request) ([]*jrpc2.ParsedRequest, error)
@@ -123,9 +118,7 @@ func (b Bridge) serveInternal(w http.ResponseWriter, req *http.Request) error {
 	}
 
 	if len(spec) != 0 {
-		// Attach the HTTP request to the client context, so the encoder can see it.
-		ctx := context.WithValue(req.Context(), httpReqKey{}, req)
-		rsps, err := b.local.Client.Batch(ctx, spec)
+		rsps, err := b.local.Client.Batch(req.Context(), spec)
 		if err != nil {
 			return err
 		}
@@ -268,18 +261,6 @@ func (o *BridgeOptions) parseGETRequest() func(*http.Request) (string, interface
 	return o.ParseGETRequest
 }
 
-type httpReqKey struct{}
-
-// HTTPRequest returns the HTTP request associated with ctx, or nil. The
-// context passed to the JSON-RPC client by the Bridge will contain this value.
-func HTTPRequest(ctx context.Context) *http.Request {
-	req, ok := ctx.Value(httpReqKey{}).(*http.Request)
-	if ok {
-		return req
-	}
-	return nil
-}
-
 // marshalError encodes an error response for an invalid request.
 func marshalError(req *jrpc2.ParsedRequest) ([]byte, error) {
 	v, err := json.Marshal(req.Error)

jhttp/getter.go

@@ -3,7 +3,6 @@
 package jhttp
 
 import (
-	"context"
 	"encoding/base64"
 	"encoding/json"
 	"errors"
@@ -74,9 +73,8 @@ func (g Getter) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 
-	ctx := context.WithValue(req.Context(), httpReqKey{}, req)
 	var result json.RawMessage
-	if err := g.local.Client.CallResult(ctx, method, params, &result); err != nil {
+	if err := g.local.Client.CallResult(req.Context(), method, params, &result); err != nil {
 		var status int
 		switch code.FromError(err) {
 		case code.MethodNotFound: