handler: Make ServeGemini accept a Context

fs.go

@@ -1,6 +1,7 @@
 package gemini
 
 import (
+	"context"
 	"fmt"
 	"io"
 	"io/fs"
@@ -31,8 +32,8 @@ type fileServer struct {
 	fs.FS
 }
 
-func (fs fileServer) ServeGemini(w ResponseWriter, r *Request) {
-	serveFile(w, r, fs, path.Clean(r.URL.Path), true)
+func (fs fileServer) ServeGemini(ctx context.Context, w ResponseWriter, r *Request) {
+	serveFile(ctx, w, r, fs, path.Clean(r.URL.Path), true)
 }
 
 // ServeContent replies to the request using the content in the
@@ -41,11 +42,11 @@ func (fs fileServer) ServeGemini(w ResponseWriter, r *Request) {
 //
 // ServeContent tries to deduce the type from name's file extension.
 // The name is otherwise unused; it is never sent in the response.
-func ServeContent(w ResponseWriter, r *Request, name string, content io.Reader) {
-	serveContent(w, name, content)
+func ServeContent(ctx context.Context, w ResponseWriter, r *Request, name string, content io.Reader) {
+	serveContent(ctx, w, name, content)
 }
 
-func serveContent(w ResponseWriter, name string, content io.Reader) {
+func serveContent(ctx context.Context, w ResponseWriter, name string, content io.Reader) {
 	// Detect mimetype from file extension
 	ext := path.Ext(name)
 	mimetype := mime.TypeByExtension(ext)
@@ -73,7 +74,7 @@ func serveContent(w ResponseWriter, name string, content io.Reader) {
 // Outside of those two special cases, ServeFile does not use r.URL.Path for
 // selecting the file or directory to serve; only the file or directory
 // provided in the name argument is used.
-func ServeFile(w ResponseWriter, r *Request, fsys fs.FS, name string) {
+func ServeFile(ctx context.Context, w ResponseWriter, r *Request, fsys fs.FS, name string) {
 	if containsDotDot(r.URL.Path) {
 		// Too many programs use r.URL.Path to construct the argument to
 		// serveFile. Reject the request under the assumption that happened
@@ -83,7 +84,7 @@ func ServeFile(w ResponseWriter, r *Request, fsys fs.FS, name string) {
 		w.WriteHeader(StatusBadRequest, "invalid URL path")
 		return
 	}
-	serveFile(w, r, fsys, name, false)
+	serveFile(ctx, w, r, fsys, name, false)
 }
 
 func containsDotDot(v string) bool {
@@ -100,7 +101,7 @@ func containsDotDot(v string) bool {
 
 func isSlashRune(r rune) bool { return r == '/' || r == '\\' }
 
-func serveFile(w ResponseWriter, r *Request, fsys fs.FS, name string, redirect bool) {
+func serveFile(ctx context.Context, w ResponseWriter, r *Request, fsys fs.FS, name string, redirect bool) {
 	const indexPage = "/index.gmi"
 
 	// Redirect .../index.gmi to .../
@@ -172,7 +173,7 @@ func serveFile(w ResponseWriter, r *Request, fsys fs.FS, name string, redirect b
 		return
 	}
 
-	serveContent(w, name, f)
+	serveContent(ctx, w, name, f)
 }
 
 func dirList(w ResponseWriter, f fs.File) {

handler.go

@@ -1,6 +1,7 @@
 package gemini
 
 import (
+	"context"
 	"net/url"
 	"strings"
 )
@@ -21,17 +22,17 @@ import (
 // response but the server doesn't log an error, panic with the value
 // ErrAbortHandler.
 type Handler interface {
-	ServeGemini(ResponseWriter, *Request)
+	ServeGemini(context.Context, ResponseWriter, *Request)
 }
 
 // The HandlerFunc type is an adapter to allow the use of ordinary functions
 // as Gemini handlers. If f is a function with the appropriate signature,
 // HandlerFunc(f) is a Handler that calls f.
-type HandlerFunc func(ResponseWriter, *Request)
+type HandlerFunc func(context.Context, ResponseWriter, *Request)
 
-// ServeGemini calls f(w, r).
-func (f HandlerFunc) ServeGemini(w ResponseWriter, r *Request) {
-	f(w, r)
+// ServeGemini calls f(ctx, w, r).
+func (f HandlerFunc) ServeGemini(ctx context.Context, w ResponseWriter, r *Request) {
+	f(ctx, w, r)
 }
 
 // RedirectHandler returns a request handler that redirects each request it
@@ -48,12 +49,12 @@ type redirectHandler struct {
 	url  string
 }
 
-func (h *redirectHandler) ServeGemini(w ResponseWriter, r *Request) {
+func (h *redirectHandler) ServeGemini(ctx context.Context, w ResponseWriter, r *Request) {
 	w.WriteHeader(h.code, h.url)
 }
 
 // NotFound replies to the request with a Gemini 51 not found error.
-func NotFound(w ResponseWriter, r *Request) {
+func NotFound(ctx context.Context, w ResponseWriter, r *Request) {
 	w.WriteHeader(StatusNotFound, "Not found")
 }
 
@@ -73,7 +74,7 @@ func StripPrefix(prefix string, h Handler) Handler {
 	if prefix == "" {
 		return h
 	}
-	return HandlerFunc(func(w ResponseWriter, r *Request) {
+	return HandlerFunc(func(ctx context.Context, w ResponseWriter, r *Request) {
 		p := strings.TrimPrefix(r.URL.Path, prefix)
 		rp := strings.TrimPrefix(r.URL.RawPath, prefix)
 		if len(p) < len(r.URL.Path) && (r.URL.RawPath == "" || len(rp) < len(r.URL.RawPath)) {
@@ -83,9 +84,9 @@ func StripPrefix(prefix string, h Handler) Handler {
 			*r2.URL = *r.URL
 			r2.URL.Path = p
 			r2.URL.RawPath = rp
-			h.ServeGemini(w, r2)
+			h.ServeGemini(ctx, w, r2)
 		} else {
-			NotFound(w, r)
+			NotFound(ctx, w, r)
 		}
 	})
 }

mux.go

@@ -1,6 +1,7 @@
 package gemini
 
 import (
+	"context"
 	"net"
 	"net/url"
 	"path"
@@ -211,9 +212,9 @@ func (mux *ServeMux) Handler(r *Request) Handler {
 
 // ServeGemini dispatches the request to the handler whose
 // pattern most closely matches the request URL.
-func (mux *ServeMux) ServeGemini(w ResponseWriter, r *Request) {
+func (mux *ServeMux) ServeGemini(ctx context.Context, w ResponseWriter, r *Request) {
 	h := mux.Handler(r)
-	h.ServeGemini(w, r)
+	h.ServeGemini(ctx, w, r)
 }
 
 // Handle registers the handler for the given pattern.
@@ -293,7 +294,7 @@ func appendSorted(es []muxEntry, e muxEntry) []muxEntry {
 }
 
 // HandleFunc registers the handler function for the given pattern.
-func (mux *ServeMux) HandleFunc(pattern string, handler func(ResponseWriter, *Request)) {
+func (mux *ServeMux) HandleFunc(pattern string, handler func(context.Context, ResponseWriter, *Request)) {
 	if handler == nil {
 		panic("gemini: nil handler")
 	}

mux_test.go

@@ -1,13 +1,14 @@
 package gemini
 
 import (
+	"context"
 	"net/url"
 	"testing"
 )
 
 type nopHandler struct{}
 
-func (*nopHandler) ServeGemini(ResponseWriter, *Request) {}
+func (*nopHandler) ServeGemini(context.Context, ResponseWriter, *Request) {}
 
 func TestServeMuxMatch(t *testing.T) {
 	type Match struct {

server.go

@@ -303,7 +303,9 @@ func (srv *Server) respond(conn net.Conn) {
 		return
 	}
 
-	h.ServeGemini(w, req)
+	// TODO: Allow configuring the server context
+	ctx := context.Background()
+	h.ServeGemini(ctx, w, req)
 	w.Flush()
 }
 

timeout.go

@@ -27,7 +27,7 @@ type timeoutHandler struct {
 	dt time.Duration
 }
 
-func (t *timeoutHandler) ServeGemini(w ResponseWriter, r *Request) {
+func (t *timeoutHandler) ServeGemini(ctx context.Context, w ResponseWriter, r *Request) {
 	ctx, cancel := context.WithTimeout(context.TODO(), t.dt)
 	defer cancel()
 
@@ -40,7 +40,7 @@ func (t *timeoutHandler) ServeGemini(w ResponseWriter, r *Request) {
 				panicChan <- p
 			}
 		}()
-		t.h.ServeGemini(tw, r)
+		t.h.ServeGemini(ctx, tw, r)
 		close(done)
 	}()