aboutsummaryrefslogtreecommitdiff
path: root/vendor/google.golang.org/cloud/compute/metadata/metadata.go
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/google.golang.org/cloud/compute/metadata/metadata.go')
-rw-r--r--vendor/google.golang.org/cloud/compute/metadata/metadata.go438
1 files changed, 0 insertions, 438 deletions
diff --git a/vendor/google.golang.org/cloud/compute/metadata/metadata.go b/vendor/google.golang.org/cloud/compute/metadata/metadata.go
deleted file mode 100644
index b791790..0000000
--- a/vendor/google.golang.org/cloud/compute/metadata/metadata.go
+++ /dev/null
@@ -1,438 +0,0 @@
-// Copyright 2014 Google Inc. All Rights Reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package metadata provides access to Google Compute Engine (GCE)
-// metadata and API service accounts.
-//
-// This package is a wrapper around the GCE metadata service,
-// as documented at https://developers.google.com/compute/docs/metadata.
-package metadata // import "google.golang.org/cloud/compute/metadata"
-
-import (
- "encoding/json"
- "fmt"
- "io/ioutil"
- "net"
- "net/http"
- "net/url"
- "os"
- "runtime"
- "strings"
- "sync"
- "time"
-
- "golang.org/x/net/context"
- "golang.org/x/net/context/ctxhttp"
-
- "google.golang.org/cloud/internal"
-)
-
-const (
- // metadataIP is the documented metadata server IP address.
- metadataIP = "169.254.169.254"
-
- // metadataHostEnv is the environment variable specifying the
- // GCE metadata hostname. If empty, the default value of
- // metadataIP ("169.254.169.254") is used instead.
- // This is variable name is not defined by any spec, as far as
- // I know; it was made up for the Go package.
- metadataHostEnv = "GCE_METADATA_HOST"
-)
-
-type cachedValue struct {
- k string
- trim bool
- mu sync.Mutex
- v string
-}
-
-var (
- projID = &cachedValue{k: "project/project-id", trim: true}
- projNum = &cachedValue{k: "project/numeric-project-id", trim: true}
- instID = &cachedValue{k: "instance/id", trim: true}
-)
-
-var (
- metaClient = &http.Client{
- Transport: &internal.Transport{
- Base: &http.Transport{
- Dial: (&net.Dialer{
- Timeout: 2 * time.Second,
- KeepAlive: 30 * time.Second,
- }).Dial,
- ResponseHeaderTimeout: 2 * time.Second,
- },
- },
- }
- subscribeClient = &http.Client{
- Transport: &internal.Transport{
- Base: &http.Transport{
- Dial: (&net.Dialer{
- Timeout: 2 * time.Second,
- KeepAlive: 30 * time.Second,
- }).Dial,
- },
- },
- }
-)
-
-// NotDefinedError is returned when requested metadata is not defined.
-//
-// The underlying string is the suffix after "/computeMetadata/v1/".
-//
-// This error is not returned if the value is defined to be the empty
-// string.
-type NotDefinedError string
-
-func (suffix NotDefinedError) Error() string {
- return fmt.Sprintf("metadata: GCE metadata %q not defined", string(suffix))
-}
-
-// Get returns a value from the metadata service.
-// The suffix is appended to "http://${GCE_METADATA_HOST}/computeMetadata/v1/".
-//
-// If the GCE_METADATA_HOST environment variable is not defined, a default of
-// 169.254.169.254 will be used instead.
-//
-// If the requested metadata is not defined, the returned error will
-// be of type NotDefinedError.
-func Get(suffix string) (string, error) {
- val, _, err := getETag(metaClient, suffix)
- return val, err
-}
-
-// getETag returns a value from the metadata service as well as the associated
-// ETag using the provided client. This func is otherwise equivalent to Get.
-func getETag(client *http.Client, suffix string) (value, etag string, err error) {
- // Using a fixed IP makes it very difficult to spoof the metadata service in
- // a container, which is an important use-case for local testing of cloud
- // deployments. To enable spoofing of the metadata service, the environment
- // variable GCE_METADATA_HOST is first inspected to decide where metadata
- // requests shall go.
- host := os.Getenv(metadataHostEnv)
- if host == "" {
- // Using 169.254.169.254 instead of "metadata" here because Go
- // binaries built with the "netgo" tag and without cgo won't
- // know the search suffix for "metadata" is
- // ".google.internal", and this IP address is documented as
- // being stable anyway.
- host = metadataIP
- }
- url := "http://" + host + "/computeMetadata/v1/" + suffix
- req, _ := http.NewRequest("GET", url, nil)
- req.Header.Set("Metadata-Flavor", "Google")
- res, err := client.Do(req)
- if err != nil {
- return "", "", err
- }
- defer res.Body.Close()
- if res.StatusCode == http.StatusNotFound {
- return "", "", NotDefinedError(suffix)
- }
- if res.StatusCode != 200 {
- return "", "", fmt.Errorf("status code %d trying to fetch %s", res.StatusCode, url)
- }
- all, err := ioutil.ReadAll(res.Body)
- if err != nil {
- return "", "", err
- }
- return string(all), res.Header.Get("Etag"), nil
-}
-
-func getTrimmed(suffix string) (s string, err error) {
- s, err = Get(suffix)
- s = strings.TrimSpace(s)
- return
-}
-
-func (c *cachedValue) get() (v string, err error) {
- defer c.mu.Unlock()
- c.mu.Lock()
- if c.v != "" {
- return c.v, nil
- }
- if c.trim {
- v, err = getTrimmed(c.k)
- } else {
- v, err = Get(c.k)
- }
- if err == nil {
- c.v = v
- }
- return
-}
-
-var (
- onGCEOnce sync.Once
- onGCE bool
-)
-
-// OnGCE reports whether this process is running on Google Compute Engine.
-func OnGCE() bool {
- onGCEOnce.Do(initOnGCE)
- return onGCE
-}
-
-func initOnGCE() {
- onGCE = testOnGCE()
-}
-
-func testOnGCE() bool {
- // The user explicitly said they're on GCE, so trust them.
- if os.Getenv(metadataHostEnv) != "" {
- return true
- }
-
- ctx, cancel := context.WithCancel(context.Background())
- defer cancel()
-
- resc := make(chan bool, 2)
-
- // Try two strategies in parallel.
- // See https://github.com/GoogleCloudPlatform/gcloud-golang/issues/194
- go func() {
- res, err := ctxhttp.Get(ctx, metaClient, "http://"+metadataIP)
- if err != nil {
- resc <- false
- return
- }
- defer res.Body.Close()
- resc <- res.Header.Get("Metadata-Flavor") == "Google"
- }()
-
- go func() {
- addrs, err := net.LookupHost("metadata.google.internal")
- if err != nil || len(addrs) == 0 {
- resc <- false
- return
- }
- resc <- strsContains(addrs, metadataIP)
- }()
-
- tryHarder := systemInfoSuggestsGCE()
- if tryHarder {
- res := <-resc
- if res {
- // The first strategy succeeded, so let's use it.
- return true
- }
- // Wait for either the DNS or metadata server probe to
- // contradict the other one and say we are running on
- // GCE. Give it a lot of time to do so, since the system
- // info already suggests we're running on a GCE BIOS.
- timer := time.NewTimer(5 * time.Second)
- defer timer.Stop()
- select {
- case res = <-resc:
- return res
- case <-timer.C:
- // Too slow. Who knows what this system is.
- return false
- }
- }
-
- // There's no hint from the system info that we're running on
- // GCE, so use the first probe's result as truth, whether it's
- // true or false. The goal here is to optimize for speed for
- // users who are NOT running on GCE. We can't assume that
- // either a DNS lookup or an HTTP request to a blackholed IP
- // address is fast. Worst case this should return when the
- // metaClient's Transport.ResponseHeaderTimeout or
- // Transport.Dial.Timeout fires (in two seconds).
- return <-resc
-}
-
-// systemInfoSuggestsGCE reports whether the local system (without
-// doing network requests) suggests that we're running on GCE. If this
-// returns true, testOnGCE tries a bit harder to reach its metadata
-// server.
-func systemInfoSuggestsGCE() bool {
- if runtime.GOOS != "linux" {
- // We don't have any non-Linux clues available, at least yet.
- return false
- }
- slurp, _ := ioutil.ReadFile("/sys/class/dmi/id/product_name")
- name := strings.TrimSpace(string(slurp))
- return name == "Google" || name == "Google Compute Engine"
-}
-
-// Subscribe subscribes to a value from the metadata service.
-// The suffix is appended to "http://${GCE_METADATA_HOST}/computeMetadata/v1/".
-// The suffix may contain query parameters.
-//
-// Subscribe calls fn with the latest metadata value indicated by the provided
-// suffix. If the metadata value is deleted, fn is called with the empty string
-// and ok false. Subscribe blocks until fn returns a non-nil error or the value
-// is deleted. Subscribe returns the error value returned from the last call to
-// fn, which may be nil when ok == false.
-func Subscribe(suffix string, fn func(v string, ok bool) error) error {
- const failedSubscribeSleep = time.Second * 5
-
- // First check to see if the metadata value exists at all.
- val, lastETag, err := getETag(subscribeClient, suffix)
- if err != nil {
- return err
- }
-
- if err := fn(val, true); err != nil {
- return err
- }
-
- ok := true
- if strings.ContainsRune(suffix, '?') {
- suffix += "&wait_for_change=true&last_etag="
- } else {
- suffix += "?wait_for_change=true&last_etag="
- }
- for {
- val, etag, err := getETag(subscribeClient, suffix+url.QueryEscape(lastETag))
- if err != nil {
- if _, deleted := err.(NotDefinedError); !deleted {
- time.Sleep(failedSubscribeSleep)
- continue // Retry on other errors.
- }
- ok = false
- }
- lastETag = etag
-
- if err := fn(val, ok); err != nil || !ok {
- return err
- }
- }
-}
-
-// ProjectID returns the current instance's project ID string.
-func ProjectID() (string, error) { return projID.get() }
-
-// NumericProjectID returns the current instance's numeric project ID.
-func NumericProjectID() (string, error) { return projNum.get() }
-
-// InternalIP returns the instance's primary internal IP address.
-func InternalIP() (string, error) {
- return getTrimmed("instance/network-interfaces/0/ip")
-}
-
-// ExternalIP returns the instance's primary external (public) IP address.
-func ExternalIP() (string, error) {
- return getTrimmed("instance/network-interfaces/0/access-configs/0/external-ip")
-}
-
-// Hostname returns the instance's hostname. This will be of the form
-// "<instanceID>.c.<projID>.internal".
-func Hostname() (string, error) {
- return getTrimmed("instance/hostname")
-}
-
-// InstanceTags returns the list of user-defined instance tags,
-// assigned when initially creating a GCE instance.
-func InstanceTags() ([]string, error) {
- var s []string
- j, err := Get("instance/tags")
- if err != nil {
- return nil, err
- }
- if err := json.NewDecoder(strings.NewReader(j)).Decode(&s); err != nil {
- return nil, err
- }
- return s, nil
-}
-
-// InstanceID returns the current VM's numeric instance ID.
-func InstanceID() (string, error) {
- return instID.get()
-}
-
-// InstanceName returns the current VM's instance ID string.
-func InstanceName() (string, error) {
- host, err := Hostname()
- if err != nil {
- return "", err
- }
- return strings.Split(host, ".")[0], nil
-}
-
-// Zone returns the current VM's zone, such as "us-central1-b".
-func Zone() (string, error) {
- zone, err := getTrimmed("instance/zone")
- // zone is of the form "projects/<projNum>/zones/<zoneName>".
- if err != nil {
- return "", err
- }
- return zone[strings.LastIndex(zone, "/")+1:], nil
-}
-
-// InstanceAttributes returns the list of user-defined attributes,
-// assigned when initially creating a GCE VM instance. The value of an
-// attribute can be obtained with InstanceAttributeValue.
-func InstanceAttributes() ([]string, error) { return lines("instance/attributes/") }
-
-// ProjectAttributes returns the list of user-defined attributes
-// applying to the project as a whole, not just this VM. The value of
-// an attribute can be obtained with ProjectAttributeValue.
-func ProjectAttributes() ([]string, error) { return lines("project/attributes/") }
-
-func lines(suffix string) ([]string, error) {
- j, err := Get(suffix)
- if err != nil {
- return nil, err
- }
- s := strings.Split(strings.TrimSpace(j), "\n")
- for i := range s {
- s[i] = strings.TrimSpace(s[i])
- }
- return s, nil
-}
-
-// InstanceAttributeValue returns the value of the provided VM
-// instance attribute.
-//
-// If the requested attribute is not defined, the returned error will
-// be of type NotDefinedError.
-//
-// InstanceAttributeValue may return ("", nil) if the attribute was
-// defined to be the empty string.
-func InstanceAttributeValue(attr string) (string, error) {
- return Get("instance/attributes/" + attr)
-}
-
-// ProjectAttributeValue returns the value of the provided
-// project attribute.
-//
-// If the requested attribute is not defined, the returned error will
-// be of type NotDefinedError.
-//
-// ProjectAttributeValue may return ("", nil) if the attribute was
-// defined to be the empty string.
-func ProjectAttributeValue(attr string) (string, error) {
- return Get("project/attributes/" + attr)
-}
-
-// Scopes returns the service account scopes for the given account.
-// The account may be empty or the string "default" to use the instance's
-// main account.
-func Scopes(serviceAccount string) ([]string, error) {
- if serviceAccount == "" {
- serviceAccount = "default"
- }
- return lines("instance/service-accounts/" + serviceAccount + "/scopes")
-}
-
-func strsContains(ss []string, s string) bool {
- for _, v := range ss {
- if v == s {
- return true
- }
- }
- return false
-}