1// Copyright 2011 Google Inc. All rights reserved. 2// Use of this source code is governed by the Apache 2.0 3// license that can be found in the LICENSE file. 4 5package appengine 6 7import ( 8 "time" 9 10 "golang.org/x/net/context" 11 12 "google.golang.org/appengine/internal" 13 pb "google.golang.org/appengine/internal/app_identity" 14 modpb "google.golang.org/appengine/internal/modules" 15) 16 17// AppID returns the application ID for the current application. 18// The string will be a plain application ID (e.g. "appid"), with a 19// domain prefix for custom domain deployments (e.g. "example.com:appid"). 20func AppID(c context.Context) string { return internal.AppID(c) } 21 22// DefaultVersionHostname returns the standard hostname of the default version 23// of the current application (e.g. "my-app.appspot.com"). This is suitable for 24// use in constructing URLs. 25func DefaultVersionHostname(c context.Context) string { 26 return internal.DefaultVersionHostname(c) 27} 28 29// ModuleName returns the module name of the current instance. 30func ModuleName(c context.Context) string { 31 return internal.ModuleName(c) 32} 33 34// ModuleHostname returns a hostname of a module instance. 35// If module is the empty string, it refers to the module of the current instance. 36// If version is empty, it refers to the version of the current instance if valid, 37// or the default version of the module of the current instance. 38// If instance is empty, ModuleHostname returns the load-balancing hostname. 39func ModuleHostname(c context.Context, module, version, instance string) (string, error) { 40 req := &modpb.GetHostnameRequest{} 41 if module != "" { 42 req.Module = &module 43 } 44 if version != "" { 45 req.Version = &version 46 } 47 if instance != "" { 48 req.Instance = &instance 49 } 50 res := &modpb.GetHostnameResponse{} 51 if err := internal.Call(c, "modules", "GetHostname", req, res); err != nil { 52 return "", err 53 } 54 return *res.Hostname, nil 55} 56 57// VersionID returns the version ID for the current application. 58// It will be of the form "X.Y", where X is specified in app.yaml, 59// and Y is a number generated when each version of the app is uploaded. 60// It does not include a module name. 61func VersionID(c context.Context) string { return internal.VersionID(c) } 62 63// InstanceID returns a mostly-unique identifier for this instance. 64func InstanceID() string { return internal.InstanceID() } 65 66// Datacenter returns an identifier for the datacenter that the instance is running in. 67func Datacenter(c context.Context) string { return internal.Datacenter(c) } 68 69// ServerSoftware returns the App Engine release version. 70// In production, it looks like "Google App Engine/X.Y.Z". 71// In the development appserver, it looks like "Development/X.Y". 72func ServerSoftware() string { return internal.ServerSoftware() } 73 74// RequestID returns a string that uniquely identifies the request. 75func RequestID(c context.Context) string { return internal.RequestID(c) } 76 77// AccessToken generates an OAuth2 access token for the specified scopes on 78// behalf of service account of this application. This token will expire after 79// the returned time. 80func AccessToken(c context.Context, scopes ...string) (token string, expiry time.Time, err error) { 81 req := &pb.GetAccessTokenRequest{Scope: scopes} 82 res := &pb.GetAccessTokenResponse{} 83 84 err = internal.Call(c, "app_identity_service", "GetAccessToken", req, res) 85 if err != nil { 86 return "", time.Time{}, err 87 } 88 return res.GetAccessToken(), time.Unix(res.GetExpirationTime(), 0), nil 89} 90 91// Certificate represents a public certificate for the app. 92type Certificate struct { 93 KeyName string 94 Data []byte // PEM-encoded X.509 certificate 95} 96 97// PublicCertificates retrieves the public certificates for the app. 98// They can be used to verify a signature returned by SignBytes. 99func PublicCertificates(c context.Context) ([]Certificate, error) { 100 req := &pb.GetPublicCertificateForAppRequest{} 101 res := &pb.GetPublicCertificateForAppResponse{} 102 if err := internal.Call(c, "app_identity_service", "GetPublicCertificatesForApp", req, res); err != nil { 103 return nil, err 104 } 105 var cs []Certificate 106 for _, pc := range res.PublicCertificateList { 107 cs = append(cs, Certificate{ 108 KeyName: pc.GetKeyName(), 109 Data: []byte(pc.GetX509CertificatePem()), 110 }) 111 } 112 return cs, nil 113} 114 115// ServiceAccount returns a string representing the service account name, in 116// the form of an email address (typically app_id@appspot.gserviceaccount.com). 117func ServiceAccount(c context.Context) (string, error) { 118 req := &pb.GetServiceAccountNameRequest{} 119 res := &pb.GetServiceAccountNameResponse{} 120 121 err := internal.Call(c, "app_identity_service", "GetServiceAccountName", req, res) 122 if err != nil { 123 return "", err 124 } 125 return res.GetServiceAccountName(), err 126} 127 128// SignBytes signs bytes using a private key unique to your application. 129func SignBytes(c context.Context, bytes []byte) (keyName string, signature []byte, err error) { 130 req := &pb.SignForAppRequest{BytesToSign: bytes} 131 res := &pb.SignForAppResponse{} 132 133 if err := internal.Call(c, "app_identity_service", "SignForApp", req, res); err != nil { 134 return "", nil, err 135 } 136 return res.GetKeyName(), res.GetSignatureBytes(), nil 137} 138 139func init() { 140 internal.RegisterErrorCodeMap("app_identity_service", pb.AppIdentityServiceError_ErrorCode_name) 141 internal.RegisterErrorCodeMap("modules", modpb.ModulesServiceError_ErrorCode_name) 142} 143