Log instead of panicking in HTTP handler on GET to /index/ (no Fetcher)

And change two Camlistore instances to Perkeep.

Change-Id: Id515480ecdc0c997e1700204d63ef4cc6a8c8cc4

pkg/blobserver/gethandler/get.go

@@ -20,6 +20,7 @@ package gethandler // import "perkeep.org/pkg/blobserver/gethandler"
 import (
 	"fmt"
 	"io"
+	"log"
 	"net/http"
 	"os"
 	"regexp"
@@ -63,6 +64,12 @@ func (h *Handler) ServeHTTP(conn http.ResponseWriter, req *http.Request) {
 // ServeBlobRef serves a blob.
 func ServeBlobRef(rw http.ResponseWriter, req *http.Request, blobRef blob.Ref, fetcher blob.Fetcher) {
 	ctx := req.Context()
+	if fetcher == nil {
+		log.Printf("gethandler: no fetcher configured for %s (ref=%v)", req.URL.Path, blobRef)
+		rw.WriteHeader(http.StatusNotFound)
+		fmt.Fprintf(rw, "no fetcher configured", blobRef)
+		return
+	}
 	rc, size, err := fetcher.Fetch(ctx, blobRef)
 	switch err {
 	case nil:

pkg/serverinit/serverinit.go

@@ -86,7 +86,7 @@ type handlerLoader struct {
 }
 
 // A HandlerInstaller is anything that can register an HTTP Handler at
-// a prefix path.  Both *http.ServeMux and camlistore.org/pkg/webserver.Server
+// a prefix path.  Both *http.ServeMux and perkeep.org/pkg/webserver.Server
 // implement HandlerInstaller.
 type HandlerInstaller interface {
 	Handle(path string, h http.Handler)
@@ -109,7 +109,7 @@ func parseCamliPath(path string) (action string, err error) {
 }
 
 func unsupportedHandler(conn http.ResponseWriter, req *http.Request) {
-	httputil.BadRequestError(conn, "Unsupported camlistore path or method.")
+	httputil.BadRequestError(conn, "Unsupported Perkeep path or method.")
 }
 
 func (s *storageAndConfig) Config() *blobserver.Config {