LogDog: Enable Coordinator to load project configs

appengine/logdog/coordinator/config/projects.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 config
 
 import (
         "fmt"
         "strings"
 
         "github.com/golang/protobuf/proto"
+        "github.com/luci/gae/service/info"
         "github.com/luci/luci-go/common/config"
         "github.com/luci/luci-go/common/errors"
         log "github.com/luci/luci-go/common/logging"
         "github.com/luci/luci-go/common/parallel"
         configProto "github.com/luci/luci-go/common/proto/config"
+        "github.com/luci/luci-go/common/proto/logdog/svcconfig"
         "github.com/luci/luci-go/server/auth"
         "github.com/luci/luci-go/server/auth/identity"
         "golang.org/x/net/context"
 )
 
 const maxProjectWorkers = 32
 
 // ErrNoAccess is returned if the user has no access to the requested project.
 var ErrNoAccess = errors.New("no access")
 
+// ProjectConfigPath returns the config set and path for project-specific
+// configuration.
+//
+// A given project's configuration is named after the current App ID.
+func ProjectConfigPath(c context.Context, project config.ProjectName) (string, string) {
+        return fmt.Sprintf("projects/%s", project), fmt.Sprintf("%s.cfg", info.Get(c).AppID())
+}
+
+// ProjectConfig loads the project config protobuf from the config service.
+//
+// If the configuration was not present, config.ErrNoConfig will be returned.
+func ProjectConfig(c context.Context, project config.ProjectName) (*svcconfig.ProjectConfig, error) {
+        // TODO(dnj): When empty project is disabled, make this return
+        // config.ErrNoConfig.
+        if project == "" {
+                return &svcconfig.ProjectConfig{
+                        ReaderAuthGroups: []string{"all"},
+                }, nil
+        }
+
+        configSet, configPath := ProjectConfigPath(c, project)
+        cfg, err := config.Get(c).GetConfig(configSet, configPath, false)
+        if err != nil {
+                return nil, err
+        }
+
+        var pcfg svcconfig.ProjectConfig
+        if err := proto.UnmarshalText(cfg.Content, &pcfg); err != nil {
+                log.Fields{
+                        log.ErrorKey:  err,
+                        "configSet":   cfg.ConfigSet,
+                        "path":        cfg.Path,
+                        "contentHash": cfg.ContentHash,
+                }.Errorf(c, "Failed to unmarshal project configuration.")
+                return nil, ErrInvalidConfig
+        }
+
+        return &pcfg, nil
+}
+
 // Projects lists the registered LogDog projects.
 func Projects(c context.Context) ([]string, error) {
         projects, err := config.Get(c).GetProjects()
         if err != nil {
                 log.WithError(err).Errorf(c, "Failed to list 'luci-config' projects.")
                 return nil, err
         }
 
         // TODO(dnj): Filter this list to projects with active LogDog configs, once we
         // move to project-specific configurations.
@@ skipping 116 matching lines @@
         for i, proj := range allProjects {
                 if access[i] {
                         result = append(result, config.ProjectName(proj.ID))
                 }
         }
         return result, nil
 }
 
 func checkProjectAccess(c context.Context, ci config.Interface, proj config.ProjectName, st auth.State) (bool, error) {
         // Load the configuration for this project.
-        cfg, err := ci.GetConfig(fmt.Sprintf("projects/%s", proj), "project.cfg", false)
+        configSet, configPath := ProjectConfigPath(c, proj)
+        cfg, err := ci.GetConfig(configSet, configPath, false)
         if err != nil {
                 if err == config.ErrNoConfig {
                         // If the configuration is missing, report no access.
                         return false, nil
                 }
                 return false, err
         }
 
         var pcfg configProto.ProjectCfg
         if err := proto.UnmarshalText(cfg.Content, &pcfg); err != nil {
@@ skipping 47 matching lines @@
 
         return false, nil
 }
 
 func trimPrefix(s, p string) (string, bool) {
         if strings.HasPrefix(s, p) {
                 return s[len(p):], true
         }
         return s, false
 }