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
5// +build !appengine
6
7package internal
8
9import (
10	"log"
11	"net/http"
12	"os"
13	"strings"
14
15	netcontext "golang.org/x/net/context"
16)
17
18// These functions are implementations of the wrapper functions
19// in ../appengine/identity.go. See that file for commentary.
20
21const (
22	hDefaultVersionHostname = "X-AppEngine-Default-Version-Hostname"
23	hRequestLogId           = "X-AppEngine-Request-Log-Id"
24	hDatacenter             = "X-AppEngine-Datacenter"
25)
26
27func ctxHeaders(ctx netcontext.Context) http.Header {
28	c := fromContext(ctx)
29	if c == nil {
30		return nil
31	}
32	return c.Request().Header
33}
34
35func DefaultVersionHostname(ctx netcontext.Context) string {
36	return ctxHeaders(ctx).Get(hDefaultVersionHostname)
37}
38
39func RequestID(ctx netcontext.Context) string {
40	return ctxHeaders(ctx).Get(hRequestLogId)
41}
42
43func Datacenter(ctx netcontext.Context) string {
44	if dc := ctxHeaders(ctx).Get(hDatacenter); dc != "" {
45		return dc
46	}
47	// If the header isn't set, read zone from the metadata service.
48	// It has the format projects/[NUMERIC_PROJECT_ID]/zones/[ZONE]
49	zone, err := getMetadata("instance/zone")
50	if err != nil {
51		log.Printf("Datacenter: %v", err)
52		return ""
53	}
54	parts := strings.Split(string(zone), "/")
55	if len(parts) == 0 {
56		return ""
57	}
58	return parts[len(parts)-1]
59}
60
61func ServerSoftware() string {
62	// TODO(dsymonds): Remove fallback when we've verified this.
63	if s := os.Getenv("SERVER_SOFTWARE"); s != "" {
64		return s
65	}
66	if s := os.Getenv("GAE_ENV"); s != "" {
67		return s
68	}
69	return "Google App Engine/1.x.x"
70}
71
72// TODO(dsymonds): Remove the metadata fetches.
73
74func ModuleName(_ netcontext.Context) string {
75	if s := os.Getenv("GAE_MODULE_NAME"); s != "" {
76		return s
77	}
78	if s := os.Getenv("GAE_SERVICE"); s != "" {
79		return s
80	}
81	return string(mustGetMetadata("instance/attributes/gae_backend_name"))
82}
83
84func VersionID(_ netcontext.Context) string {
85	if s1, s2 := os.Getenv("GAE_MODULE_VERSION"), os.Getenv("GAE_MINOR_VERSION"); s1 != "" && s2 != "" {
86		return s1 + "." + s2
87	}
88	if s1, s2 := os.Getenv("GAE_VERSION"), os.Getenv("GAE_DEPLOYMENT_ID"); s1 != "" && s2 != "" {
89		return s1 + "." + s2
90	}
91	return string(mustGetMetadata("instance/attributes/gae_backend_version")) + "." + string(mustGetMetadata("instance/attributes/gae_backend_minor_version"))
92}
93
94func InstanceID() string {
95	if s := os.Getenv("GAE_MODULE_INSTANCE"); s != "" {
96		return s
97	}
98	if s := os.Getenv("GAE_INSTANCE"); s != "" {
99		return s
100	}
101	return string(mustGetMetadata("instance/attributes/gae_backend_instance"))
102}
103
104func partitionlessAppID() string {
105	// gae_project has everything except the partition prefix.
106	if appID := os.Getenv("GAE_LONG_APP_ID"); appID != "" {
107		return appID
108	}
109	if project := os.Getenv("GOOGLE_CLOUD_PROJECT"); project != "" {
110		return project
111	}
112	return string(mustGetMetadata("instance/attributes/gae_project"))
113}
114
115func fullyQualifiedAppID(_ netcontext.Context) string {
116	if s := os.Getenv("GAE_APPLICATION"); s != "" {
117		return s
118	}
119	appID := partitionlessAppID()
120
121	part := os.Getenv("GAE_PARTITION")
122	if part == "" {
123		part = string(mustGetMetadata("instance/attributes/gae_partition"))
124	}
125
126	if part != "" {
127		appID = part + "~" + appID
128	}
129	return appID
130}
131
132func IsDevAppServer() bool {
133	return os.Getenv("RUN_WITH_DEVAPPSERVER") != ""
134}
135