Package idtoken provides functionality for generating and validating ID tokens, with configurable options for audience, custom claims, and token formats.
For more information on ID tokens, see https://cloud.google.com/docs/authentication/token-types#id .
Functions
func NewCredentials
func
NewCredentials
(
opts
*
Options
)
(
*
auth
.
Credentials
,
error
)
NewCredentials creates a [cloud.google.com/go/auth.Credentials] that returns ID tokens configured by the opts provided. The parameter opts.Audience must not be empty. If both opts.CredentialsFile and opts.CredentialsJSON are empty, an attempt will be made to detect credentials from the environment (see [cloud.google.com/go/auth/credentials.DetectDefault]). Only service account, impersonated service account, external account and Compute credentials are supported.
Example
setAuthorizationHeader
package
main
import
(
"context"
"net/http"
"cloud.google.com/go/auth/credentials/idtoken"
"cloud.google.com/go/auth/httptransport"
)
func
main
()
{
ctx
:=
context
.
Background
()
audience
:=
"http://example.com"
creds
,
err
:=
idtoken
.
NewCredentials
(
& idtoken
.
Options
{
Audience
:
audience
,
})
if
err
!=
nil
{
// Handle error.
}
token
,
err
:=
creds
.
Token
(
ctx
)
if
err
!=
nil
{
// Handle error.
}
req
,
err
:=
http
.
NewRequest
(
http
.
MethodGet
,
audience
,
nil
)
if
err
!=
nil
{
// Handle error.
}
httptransport
.
SetAuthHeader
(
token
,
req
)
}
ComputeTokenFormat
type
ComputeTokenFormat
int
ComputeTokenFormat dictates the the token format when requesting an ID token from the compute metadata service.
ComputeTokenFormatDefault, ComputeTokenFormatStandard, ComputeTokenFormatFull, ComputeTokenFormatFullWithLicense
const
(
// ComputeTokenFormatDefault means the same as [ComputeTokenFormatFull].
ComputeTokenFormatDefault
ComputeTokenFormat
=
iota
// ComputeTokenFormatStandard mean only standard JWT fields will be included
// in the token.
ComputeTokenFormatStandard
// ComputeTokenFormatFull means the token will include claims about the
// virtual machine instance and its project.
ComputeTokenFormatFull
// ComputeTokenFormatFullWithLicense means the same as
// [ComputeTokenFormatFull] with the addition of claims about licenses
// associated with the instance.
ComputeTokenFormatFullWithLicense
)
Options
type
Options
struct
{
// Audience is the `aud` field for the token, such as an API endpoint the
// token will grant access to. Required.
Audience
string
// ComputeTokenFormat dictates the the token format when requesting an ID
// token from the compute metadata service. Optional.
ComputeTokenFormat
ComputeTokenFormat
// CustomClaims specifies private non-standard claims for an ID token.
// Optional.
CustomClaims
map
[
string
]
interface
{}
// CredentialsFile sources a JSON credential file from the provided
// filepath. If provided, do not provide CredentialsJSON. Optional.
CredentialsFile
string
// CredentialsJSON sources a JSON credential file from the provided bytes.
// If provided, do not provide CredentialsJSON. Optional.
CredentialsJSON
[]
byte
// Client configures the underlying client used to make network requests
// when fetching tokens. If provided this should be a fully-authenticated
// client. Optional.
Client
*
http
.
Client
}
Options for the configuration of creation of an ID token with [NewCredentials].
Payload
type
Payload
struct
{
Issuer
string
`json:"iss"`
Audience
string
`json:"aud"`
Expires
int64
`json:"exp"`
IssuedAt
int64
`json:"iat"`
Subject
string
`json:"sub,omitempty"`
Claims
map
[
string
]
interface
{}
`json:"-"`
}
Payload represents a decoded payload of an ID token.
func ParsePayload
ParsePayload parses the given token and returns its payload.
Warning: This function does not validate the token prior to parsing it.
ParsePayload is primarily meant to be used to inspect a token's payload. This is useful when validation fails and the payload needs to be inspected.
Note: A successful Validate() invocation with the same token will return an identical payload.
func Validate
Validate is used to validate the provided idToken with a known Google cert URL. If audience is not empty the audience claim of the Token is validated. Upon successful validation a parsed token Payload is returned allowing the caller to validate any additional claims.
Validator
type
Validator
struct
{
// contains filtered or unexported fields
}
Validator provides a way to validate Google ID Tokens
func NewValidator
func
NewValidator
(
opts
*
ValidatorOptions
)
(
*
Validator
,
error
)
NewValidator creates a Validator that uses the options provided to configure a the internal http.Client that will be used to make requests to fetch JWKs.
func (*Validator) Validate
func
(
v
*
Validator
)
Validate
(
ctx
context
.
Context
,
idToken
string
,
audience
string
)
(
*
Payload
,
error
)
Validate is used to validate the provided idToken with a known Google cert URL. If audience is not empty the audience claim of the Token is validated. Upon successful validation a parsed token Payload is returned allowing the caller to validate any additional claims.
ValidatorOptions
type
ValidatorOptions
struct
{
// Client used to make requests to the certs URL. Optional.
Client
*
http
.
Client
// Custom certs URL for RS256 JWK to be used. If not provided, the default
// Google oauth2 endpoint will be used. Optional.
RS256CertsURL
string
// Custom certs URL for ES256 JWK to be used. If not provided, the default
// Google IAP endpoint will be used. Optional.
ES256CertsURL
string
}
ValidatorOptions provides a way to configure a [Validator].
