remove dead code, handle errors better

handler.go

@@ -141,46 +141,6 @@ func (h handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	w.WriteHeader(http.StatusNotFound)
 	w.Write([]byte("not found"))
 	return
-
-	// switch r.URL.Path {
-	// case "/fart":
-	// 	// Step 1: a request comes in at orel.li. This page contains a meta tag
-	// 	// indicating where the package contents may be found, and which backend
-	// 	// is serving the package.
-	// 	serveFile(w, "meta/fart/root.html")
-	// case "/modules/orel.li/fart/@v/list":
-	// 	// Step 2: list all of the versions for the package. Versions may be
-	// 	// available but unlisted.
-	// 	serveFile(w, "meta/fart/version-list")
-	// case "/modules/orel.li/fart/@latest",
-	// 	"/modules/orel.li/fart/@v/v0.0.3.info":
-	// 	// Step 3: get info for the version, which is just a timestamp at the
-	// 	// moment.
-	// 	e := json.NewEncoder(w)
-	// 	e.Encode(versionInfo{
-	// 		Version: "v0.0.3",
-	// 		Time:    time.Now(),
-	// 	})
-	// case "/modules/orel.li/fart/@v/v0.0.3.mod":
-	// 	// Step 4: retrieve the modfile for the package, informing go mod of
-	// 	// any transitive dependencies.
-	// 	serveFile(w, "meta/fart/modfile")
-	// case "/modules/orel.li/fart/@v/v0.0.3.zip":
-	// 	// Step 5: retrieve the source code contents for a package, as a
-	// 	// specially-formatted zip file.
-	// 	err := zip.CreateFromDir(w, module.Version{
-	// 		Path:    "orel.li/fart",
-	// 		Version: "v0.0.3",
-	// 	}, "/home/jorelli/mir/modules/orel.li/fart")
-	// 	if err != nil {
-	// 		log_error.Printf("zip error: %v", err)
-	// 	}
-	// case "/":
-	// 	w.WriteHeader(http.StatusOK)
-	// default:
-	// 	w.WriteHeader(http.StatusNotFound)
-	// 	w.Write([]byte("not found"))
-	// }
 }
 
 // locate searches our module root for a given modpath
@@ -334,7 +294,9 @@ func (h handler) modfile(modpath, modversion string, w http.ResponseWriter, r *h
 	}
 	defer f.Close()
 
-	io.Copy(w, f)
+	if _, err := io.Copy(w, f); err != nil {
+		log_error.Printf("error copying modfile contents for %s version %s: %v", modpath, modversion, err)
+	}
 }
 
 // zipfile serves the $base/$module/@v/$version.zip endpoint