From 50fe7a2fda092dc3a863f4173d981c7adbe17f86 Mon Sep 17 00:00:00 2001
From: Brad Fitzpatrick <brad@danga.com>
Date: Sun, 13 May 2012 13:02:20 -0700
Subject: [PATCH] Make UI discovery have absolute paths, so root discovery
 using UI's discovery handler works.

Change-Id: Ieb1b5d143c528b4b15875aa810038c3ebdf30251
---
 pkg/blobserver/registry.go       | 3 +++
 pkg/server/ui.go                 | 9 ++++++---
 pkg/serverconfig/serverconfig.go | 7 +++++++
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/pkg/blobserver/registry.go b/pkg/blobserver/registry.go
index e5b472736..c1038fa1b 100644
--- a/pkg/blobserver/registry.go
+++ b/pkg/blobserver/registry.go
@@ -28,6 +28,9 @@ import (
 var ErrHandlerTypeNotFound = errors.New("requested handler type not loaded")
 
 type Loader interface {
+	// MyPrefix returns the prefix of the handler currently being constructed.
+	MyPrefix() string
+
 	GetStorage(prefix string) (Storage, error)
 	GetHandlerType(prefix string) string // returns "" if unknown
 
diff --git a/pkg/server/ui.go b/pkg/server/ui.go
index ca84b71fb..52518d8b1 100644
--- a/pkg/server/ui.go
+++ b/pkg/server/ui.go
@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"log"
 	"net/http"
+	"path"
 	"regexp"
 	"strconv"
 	"strings"
@@ -61,6 +62,7 @@ type UIHandler struct {
 
 	PublishRoots map[string]*PublishHandler
 
+	prefix  string             // of the UI handler itself
 	Storage blobserver.Storage // of BlobRoot
 	Cache   blobserver.Storage // or nil
 	Search  *search.Handler    // or nil
@@ -75,6 +77,7 @@ func init() {
 
 func newUIFromConfig(ld blobserver.Loader, conf jsonconfig.Obj) (h http.Handler, err error) {
 	ui := &UIHandler{
+		prefix:       ld.MyPrefix(),
 		BlobRoot:     conf.OptionalString("blobRoot", ""),
 		SearchRoot:   conf.OptionalString("searchRoot", ""),
 		JSONSignRoot: conf.OptionalString("jsonSignRoot", ""),
@@ -257,9 +260,9 @@ func (ui *UIHandler) serveDiscovery(rw http.ResponseWriter, req *http.Request) {
 		"blobRoot":        ui.BlobRoot,
 		"searchRoot":      ui.SearchRoot,
 		"jsonSignRoot":    ui.JSONSignRoot,
-		"uploadHelper":    "?camli.mode=uploadhelper", // hack; remove with better javascript
-		"downloadHelper":  "./download/",
-		"directoryHelper": "./tree/",
+		"uploadHelper":    ui.prefix + "?camli.mode=uploadhelper", // hack; remove with better javascript
+		"downloadHelper":  path.Join(ui.prefix, "download") + "/",
+		"directoryHelper": path.Join(ui.prefix, "tree") + "/",
 		"publishRoots":    pubRoots,
 	})
 }
diff --git a/pkg/serverconfig/serverconfig.go b/pkg/serverconfig/serverconfig.go
index 9f7c441d9..c7210831e 100644
--- a/pkg/serverconfig/serverconfig.go
+++ b/pkg/serverconfig/serverconfig.go
@@ -50,6 +50,7 @@ type handlerLoader struct {
 	baseURL   string
 	config    map[string]*handlerConfig // prefix -> config
 	handler   map[string]interface{}    // prefix -> http.Handler / func / blobserver.Storage
+	curPrefix string
 
 	// optional context (for App Engine, the first request that
 	// started up the process).  we may need this if setting up
@@ -186,6 +187,10 @@ func (hl *handlerLoader) getOrSetup(prefix string) interface{} {
 	return hl.handler[prefix]
 }
 
+func (hl *handlerLoader) MyPrefix() string {
+	return hl.curPrefix
+}
+
 func (hl *handlerLoader) GetStorage(prefix string) (blobserver.Storage, error) {
 	hl.setupHandler(prefix)
 	if s, ok := hl.handler[prefix].(blobserver.Storage); ok {
@@ -243,6 +248,8 @@ func (hl *handlerLoader) setupHandler(prefix string) {
 		}
 	}()
 
+	hl.curPrefix = prefix
+
 	if strings.HasPrefix(h.htype, "storage-") {
 		stype := h.htype[len("storage-"):]
 		// Assume a storage interface