Service Metadata API - Package cloud.google.com/go/compute/metadata (v0.6.0)

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://cloud.google.com/compute/docs/metadata/overview.

Functions

func Email (deprecated)

func Email(serviceAccount string) (string, error)

Email calls Client.EmailWithContext on the default client.

Deprecated: Please use the context aware variant [EmailWithContext].

func EmailWithContext 

func EmailWithContext(ctx context.Context, serviceAccount string) (string, error)

EmailWithContext calls Client.EmailWithContext on the default client.

func ExternalIP (deprecated)

func ExternalIP() (string, error)

ExternalIP returns the instance's primary external (public) IP address.

Deprecated: Please use the context aware variant [ExternalIPWithContext].

func ExternalIPWithContext 

func ExternalIPWithContext(ctx context.Context) (string, error)

ExternalIPWithContext returns the instance's primary external (public) IP address.

func Get (deprecated)

func Get(suffix string) (string, error)

Get calls Client.GetWithContext on the default client.

Deprecated: Please use the context aware variant [GetWithContext].

func GetWithContext 

func GetWithContext(ctx context.Context, suffix string) (string, error)

GetWithContext calls Client.GetWithContext on the default client.

func Hostname (deprecated)

func Hostname() (string, error)

Hostname returns the instance's hostname. This will be of the form "

Deprecated: Please use the context aware variant [HostnameWithContext].

func HostnameWithContext 

func HostnameWithContext(ctx context.Context) (string, error)

HostnameWithContext returns the instance's hostname. This will be of the form "

func InstanceAttributeValue (deprecated)

func InstanceAttributeValue(attr string) (string, error)

InstanceAttributeValue calls Client.InstanceAttributeValueWithContext on the default client.

Deprecated: Please use the context aware variant [InstanceAttributeValueWithContext].

func InstanceAttributeValueWithContext 

func InstanceAttributeValueWithContext(ctx context.Context, attr string) (string, error)

InstanceAttributeValueWithContext calls Client.InstanceAttributeValueWithContext on the default client.

func InstanceAttributes (deprecated)

func InstanceAttributes() ([]string, error)

InstanceAttributes calls Client.InstanceAttributesWithContext on the default client.

Deprecated: Please use the context aware variant [InstanceAttributesWithContext.

func InstanceAttributesWithContext 

func InstanceAttributesWithContext(ctx context.Context) ([]string, error)

InstanceAttributesWithContext calls Client.ProjectAttributesWithContext on the default client.

func InstanceID (deprecated)

func InstanceID() (string, error)

InstanceID returns the current VM's numeric instance ID.

Deprecated: Please use the context aware variant [InstanceIDWithContext].

func InstanceIDWithContext 

func InstanceIDWithContext(ctx context.Context) (string, error)

InstanceIDWithContext returns the current VM's numeric instance ID.

func InstanceName (deprecated)

func InstanceName() (string, error)

InstanceName returns the current VM's instance ID string.

Deprecated: Please use the context aware variant [InstanceNameWithContext].

func InstanceNameWithContext 

func InstanceNameWithContext(ctx context.Context) (string, error)

InstanceNameWithContext returns the current VM's instance ID string.

func InstanceTags (deprecated)

func InstanceTags() ([]string, error)

InstanceTags returns the list of user-defined instance tags, assigned when initially creating a GCE instance.

Deprecated: Please use the context aware variant [InstanceTagsWithContext].

func InstanceTagsWithContext 

func InstanceTagsWithContext(ctx context.Context) ([]string, error)

InstanceTagsWithContext returns the list of user-defined instance tags, assigned when initially creating a GCE instance.

func InternalIP (deprecated)

func InternalIP() (string, error)

InternalIP returns the instance's primary internal IP address.

Deprecated: Please use the context aware variant [InternalIPWithContext].

func InternalIPWithContext 

func InternalIPWithContext(ctx context.Context) (string, error)

InternalIPWithContext returns the instance's primary internal IP address.

func NumericProjectID (deprecated)

func NumericProjectID() (string, error)

NumericProjectID returns the current instance's numeric project ID.

Deprecated: Please use the context aware variant [NumericProjectIDWithContext].

func NumericProjectIDWithContext 

func NumericProjectIDWithContext(ctx context.Context) (string, error)

NumericProjectIDWithContext returns the current instance's numeric project ID.

func OnGCE 

func OnGCE() bool

OnGCE reports whether this process is running on Google Compute Platforms. NOTE: True returned from OnGCE does not guarantee that the metadata server is accessible from this process and have all the metadata defined.

func ProjectAttributeValue (deprecated)

func ProjectAttributeValue(attr string) (string, error)

ProjectAttributeValue calls Client.ProjectAttributeValueWithContext on the default client.

Deprecated: Please use the context aware variant [ProjectAttributeValueWithContext].

func ProjectAttributeValueWithContext 

func ProjectAttributeValueWithContext(ctx context.Context, attr string) (string, error)

ProjectAttributeValueWithContext calls Client.ProjectAttributeValueWithContext on the default client.

func ProjectAttributes (deprecated)

func ProjectAttributes() ([]string, error)

ProjectAttributes calls Client.ProjectAttributesWithContext on the default client.

Deprecated: Please use the context aware variant [ProjectAttributesWithContext].

func ProjectAttributesWithContext 

func ProjectAttributesWithContext(ctx context.Context) ([]string, error)

ProjectAttributesWithContext calls Client.ProjectAttributesWithContext on the default client.

func ProjectID (deprecated)

func ProjectID() (string, error)

ProjectID returns the current instance's project ID string.

Deprecated: Please use the context aware variant [ProjectIDWithContext].

func ProjectIDWithContext 

func ProjectIDWithContext(ctx context.Context) (string, error)

ProjectIDWithContext returns the current instance's project ID string.

func Scopes (deprecated)

func Scopes(serviceAccount string) ([]string, error)

Scopes calls Client.ScopesWithContext on the default client.

Deprecated: Please use the context aware variant [ScopesWithContext].

func ScopesWithContext 

func ScopesWithContext(ctx context.Context, serviceAccount string) ([]string, error)

ScopesWithContext calls Client.ScopesWithContext on the default client.

func Subscribe (deprecated)

func Subscribe(suffix string, fn func(v string, ok bool) error) error

Subscribe calls Client.SubscribeWithContext on the default client.

Deprecated: Please use the context aware variant [SubscribeWithContext].

func SubscribeWithContext 

func SubscribeWithContext(ctx context.Context, suffix string, fn func(ctx context.Context, v string, ok bool) error) error

SubscribeWithContext calls Client.SubscribeWithContext on the default client.

func Zone (deprecated)

func Zone() (string, error)

Zone returns the current VM's zone, such as "us-central1-b".

Deprecated: Please use the context aware variant [ZoneWithContext].

func ZoneWithContext 

func ZoneWithContext(ctx context.Context) (string, error)

ZoneWithContext returns the current VM's zone, such as "us-central1-b".

Client

type Client struct {
	// contains filtered or unexported fields
}

A Client provides metadata.

func NewClient 

func NewClient(c *http.Client) *Client

NewClient returns a Client that can be used to fetch metadata. Returns the client that uses the specified http.Client for HTTP requests. If nil is specified, returns the default client.

Example

package main

import (
	"context"
	"net/http"

	"cloud.google.com/go/compute/metadata"
)

// This example demonstrates how to use your own transport when using this package.
func main() {
	ctx := context.Background()
	c := metadata.NewClient(&http.Client{Transport: userAgentTransport{
		userAgent: "my-user-agent",
		base:      http.DefaultTransport,
	}})
	pID, err := c.GetWithContext(ctx, "project/project-id")
	if err != nil {
		// TODO: Handle error.
	}
	_ = pID // TODO: Use p.
}

// userAgentTransport sets the User-Agent header before calling base.
type userAgentTransport struct {
	userAgent string
	base      http.RoundTripper
}

// RoundTrip implements the http.RoundTripper interface.
func (t userAgentTransport) RoundTrip(req *http.Request) (*http.Response, error) {
	req.Header.Set("User-Agent", t.userAgent)
	return t.base.RoundTrip(req)
}

func NewWithOptions 

func NewWithOptions(opts *Options) *Client

NewWithOptions returns a Client that is configured with the provided Options.

func (*Client) Email (deprecated)

func (c *Client) Email(serviceAccount string) (string, error)

Email returns the email address associated with the service account.

Deprecated: Please use the context aware variant [Client.EmailWithContext].

func (*Client) EmailWithContext 

func (c *Client) EmailWithContext(ctx context.Context, serviceAccount string) (string, error)

EmailWithContext returns the email address associated with the service account. The serviceAccount parameter default value (empty string or "default" value) will use the instance's main account.

func (*Client) ExternalIP (deprecated)

func (c *Client) ExternalIP() (string, error)

ExternalIP returns the instance's primary external (public) IP address.

Deprecated: Please use the context aware variant [Client.ExternalIPWithContext].

func (*Client) ExternalIPWithContext 

func (c *Client) ExternalIPWithContext(ctx context.Context) (string, error)

ExternalIPWithContext returns the instance's primary external (public) IP address.

func (*Client) Get (deprecated)

func (c *Client) Get(suffix string) (string, error)

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.

Deprecated: Please use the context aware variant [Client.GetWithContext].

func (*Client) GetWithContext 

func (c *Client) GetWithContext(ctx context.Context, suffix string) (string, error)

GetWithContext 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.

NOTE: Without an extra deadline in the context this call can take in the worst case, with internal backoff retries, up to 15 seconds (e.g. when server is responding slowly). Pass context with additional timeouts when needed.

func (*Client) Hostname (deprecated)

func (c *Client) Hostname() (string, error)

Hostname returns the instance's hostname. This will be of the form "

Deprecated: Please use the context aware variant [Client.HostnameWithContext].

func (*Client) HostnameWithContext 

func (c *Client) HostnameWithContext(ctx context.Context) (string, error)

HostnameWithContext returns the instance's hostname. This will be of the form "

func (*Client) InstanceAttributeValue (deprecated)

func (c *Client) InstanceAttributeValue(attr string) (string, error)

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.

Deprecated: Please use the context aware variant [Client.InstanceAttributeValueWithContext].

func (*Client) InstanceAttributeValueWithContext 

func (c *Client) InstanceAttributeValueWithContext(ctx context.Context, attr string) (string, error)

InstanceAttributeValueWithContext 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 (*Client) InstanceAttributes (deprecated)

func (c *Client) InstanceAttributes() ([]string, error)

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.

Deprecated: Please use the context aware variant [Client.InstanceAttributesWithContext].

func (*Client) InstanceAttributesWithContext 

func (c *Client) InstanceAttributesWithContext(ctx context.Context) ([]string, error)

InstanceAttributesWithContext 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 (*Client) InstanceID (deprecated)

func (c *Client) InstanceID() (string, error)

InstanceID returns the current VM's numeric instance ID.

Deprecated: Please use the context aware variant [Client.InstanceIDWithContext].

func (*Client) InstanceIDWithContext 

func (c *Client) InstanceIDWithContext(ctx context.Context) (string, error)

InstanceIDWithContext returns the current VM's numeric instance ID.

func (*Client) InstanceName (deprecated)

func (c *Client) InstanceName() (string, error)

InstanceName returns the current VM's instance ID string.

Deprecated: Please use the context aware variant [Client.InstanceNameWithContext].

func (*Client) InstanceNameWithContext 

func (c *Client) InstanceNameWithContext(ctx context.Context) (string, error)

InstanceNameWithContext returns the current VM's instance ID string.

func (*Client) InstanceTags (deprecated)

func (c *Client) InstanceTags() ([]string, error)

InstanceTags returns the list of user-defined instance tags.

Deprecated: Please use the context aware variant [Client.InstanceTagsWithContext].

func (*Client) InstanceTagsWithContext 

func (c *Client) InstanceTagsWithContext(ctx context.Context) ([]string, error)

InstanceTagsWithContext returns the list of user-defined instance tags, assigned when initially creating a GCE instance.

func (*Client) InternalIP (deprecated)

func (c *Client) InternalIP() (string, error)

InternalIP returns the instance's primary internal IP address.

Deprecated: Please use the context aware variant [Client.InternalIPWithContext].

func (*Client) InternalIPWithContext 

func (c *Client) InternalIPWithContext(ctx context.Context) (string, error)

InternalIPWithContext returns the instance's primary internal IP address.

func (*Client) NumericProjectID (deprecated)

func (c *Client) NumericProjectID() (string, error)

NumericProjectID returns the current instance's numeric project ID.

Deprecated: Please use the context aware variant [Client.NumericProjectIDWithContext].

func (*Client) NumericProjectIDWithContext 

func (c *Client) NumericProjectIDWithContext(ctx context.Context) (string, error)

NumericProjectIDWithContext returns the current instance's numeric project ID.

func (*Client) ProjectAttributeValue (deprecated)

func (c *Client) ProjectAttributeValue(attr string) (string, error)

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.

Deprecated: Please use the context aware variant [Client.ProjectAttributeValueWithContext].

func (*Client) ProjectAttributeValueWithContext 

func (c *Client) ProjectAttributeValueWithContext(ctx context.Context, attr string) (string, error)

ProjectAttributeValueWithContext 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 (*Client) ProjectAttributes (deprecated)

func (c *Client) ProjectAttributes() ([]string, error)

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.

Deprecated: Please use the context aware variant [Client.ProjectAttributesWithContext].

func (*Client) ProjectAttributesWithContext 

func (c *Client) ProjectAttributesWithContext(ctx context.Context) ([]string, error)

ProjectAttributesWithContext 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 (*Client) ProjectID (deprecated)

func (c *Client) ProjectID() (string, error)

ProjectID returns the current instance's project ID string.

Deprecated: Please use the context aware variant [Client.ProjectIDWithContext].

func (*Client) ProjectIDWithContext 

func (c *Client) ProjectIDWithContext(ctx context.Context) (string, error)

ProjectIDWithContext returns the current instance's project ID string.

func (*Client) Scopes (deprecated)

func (c *Client) Scopes(serviceAccount string) ([]string, error)

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.

Deprecated: Please use the context aware variant [Client.ScopesWithContext].

func (*Client) ScopesWithContext 

func (c *Client) ScopesWithContext(ctx context.Context, serviceAccount string) ([]string, error)

ScopesWithContext 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 (*Client) Subscribe (deprecated)

func (c *Client) Subscribe(suffix string, fn func(v string, ok bool) error) error

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.

Deprecated: Please use the context aware variant [Client.SubscribeWithContext].

func (*Client) SubscribeWithContext 

func (c *Client) SubscribeWithContext(ctx context.Context, suffix string, fn func(ctx context.Context, v string, ok bool) error) error

SubscribeWithContext 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.

SubscribeWithContext 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 (*Client) Zone (deprecated)

func (c *Client) Zone() (string, error)

Zone returns the current VM's zone, such as "us-central1-b".

Deprecated: Please use the context aware variant [Client.ZoneWithContext].

func (*Client) ZoneWithContext 

func (c *Client) ZoneWithContext(ctx context.Context) (string, error)

ZoneWithContext returns the current VM's zone, such as "us-central1-b".

Error

type Error struct {
	// Code is the HTTP response status code.
	Code int
	// Message is the server response message.
	Message string
}

Error contains an error response from the server.

func (*Error) Error 

func (e *Error) Error() string

NotDefinedError

type NotDefinedError string

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.

func (NotDefinedError) Error 

func (suffix NotDefinedError) Error() string

Options

type Options struct {
	// Client is the HTTP client used to make requests. Optional.
	Client *http.Client
	// Logger is used to log information about HTTP request and responses.
	// If not provided, nothing will be logged. Optional.
	Logger *slog.Logger
}

Options for configuring a [Client].