LogDog: Enable Coordinator to load project configs

appengine/logdog/coordinator/project.go

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package coordinator
 
 import (
         "strings"
 
         "github.com/luci/gae/service/datastore/meta"
+        "github.com/luci/gae/service/info"
         "github.com/luci/luci-go/common/config"
+        "github.com/luci/luci-go/common/proto/logdog/svcconfig"
         "golang.org/x/net/context"
 )
 
 // projectNamespacePrefix is the datastore namespace prefix for project
 // namespaces.
 const projectNamespacePrefix = "luci."
 
 // ProjectNamespace returns the AppEngine namespace for a given luci-config
 // project name.
 func ProjectNamespace(project config.ProjectName) string {
         return projectNamespacePrefix + string(project)
 }
 
 // ProjectFromNamespace returns the current project installed in the supplied
 // Context's namespace.
 //
 // If the namespace does not have a project namespace prefix, this function
 // will return an empty string.
 func ProjectFromNamespace(ns string) config.ProjectName {
         if !strings.HasPrefix(ns, projectNamespacePrefix) {
                 return ""
         }
         return config.ProjectName(ns[len(projectNamespacePrefix):])
 }
 
+// CurrentProject returns the current project based on the currently-loaded
+// namespace.
+//
+// If there is no current namespace, or if the current namespace is not a valid
+// project namespace, an empty string will be returned.
+func CurrentProject(c context.Context) config.ProjectName {
+        if ns, ok := info.Get(c).GetNamespace(); ok {
+                return ProjectFromNamespace(ns)
+        }
+        return ""
+}
+
+// CurrentProjectConfig returns the project-specific configuration for the
+// current project.
+//
+// If there is no current project namespace, or if the current project has no
+// configuration, config.ErrInvalidConfig will be returned.
+func CurrentProjectConfig(c context.Context) (*svcconfig.ProjectConfig, error) {
+        return GetServices(c).ProjectConfig(c, CurrentProject(c))
+}
+
 // AllProjectsWithNamespaces scans current namespaces and returns those that
 // belong to LUCI projects.
 func AllProjectsWithNamespaces(c context.Context) ([]config.ProjectName, error) {
         var projects []config.ProjectName
         err := meta.NamespacesWithPrefix(c, projectNamespacePrefix, func(ns string) error {
                 if proj := ProjectFromNamespace(ns); proj != "" {
                         projects = append(projects, proj)
                 }
                 return nil
         })
         if err != nil {
                 return nil, err
         }
         return projects, nil
 }