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Vendor main dependencies.

This commit is contained in:
Timo Reimann 2017-02-07 22:33:23 +01:00
parent 49a09ab7dd
commit dd5e3fba01
2738 changed files with 1045689 additions and 0 deletions

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package credentials
import (
"github.com/aws/aws-sdk-go/aws/awserr"
)
var (
// ErrNoValidProvidersFoundInChain Is returned when there are no valid
// providers in the ChainProvider.
//
// This has been deprecated. For verbose error messaging set
// aws.Config.CredentialsChainVerboseErrors to true
//
// @readonly
ErrNoValidProvidersFoundInChain = awserr.New("NoCredentialProviders",
`no valid providers in chain. Deprecated.
For verbose messaging see aws.Config.CredentialsChainVerboseErrors`,
nil)
)
// A ChainProvider will search for a provider which returns credentials
// and cache that provider until Retrieve is called again.
//
// The ChainProvider provides a way of chaining multiple providers together
// which will pick the first available using priority order of the Providers
// in the list.
//
// If none of the Providers retrieve valid credentials Value, ChainProvider's
// Retrieve() will return the error ErrNoValidProvidersFoundInChain.
//
// If a Provider is found which returns valid credentials Value ChainProvider
// will cache that Provider for all calls to IsExpired(), until Retrieve is
// called again.
//
// Example of ChainProvider to be used with an EnvProvider and EC2RoleProvider.
// In this example EnvProvider will first check if any credentials are available
// via the environment variables. If there are none ChainProvider will check
// the next Provider in the list, EC2RoleProvider in this case. If EC2RoleProvider
// does not return any credentials ChainProvider will return the error
// ErrNoValidProvidersFoundInChain
//
// creds := NewChainCredentials(
// []Provider{
// &EnvProvider{},
// &EC2RoleProvider{
// Client: ec2metadata.New(sess),
// },
// })
//
// // Usage of ChainCredentials with aws.Config
// svc := ec2.New(&aws.Config{Credentials: creds})
//
type ChainProvider struct {
Providers []Provider
curr Provider
VerboseErrors bool
}
// NewChainCredentials returns a pointer to a new Credentials object
// wrapping a chain of providers.
func NewChainCredentials(providers []Provider) *Credentials {
return NewCredentials(&ChainProvider{
Providers: append([]Provider{}, providers...),
})
}
// Retrieve returns the credentials value or error if no provider returned
// without error.
//
// If a provider is found it will be cached and any calls to IsExpired()
// will return the expired state of the cached provider.
func (c *ChainProvider) Retrieve() (Value, error) {
var errs []error
for _, p := range c.Providers {
creds, err := p.Retrieve()
if err == nil {
c.curr = p
return creds, nil
}
errs = append(errs, err)
}
c.curr = nil
var err error
err = ErrNoValidProvidersFoundInChain
if c.VerboseErrors {
err = awserr.NewBatchError("NoCredentialProviders", "no valid providers in chain", errs)
}
return Value{}, err
}
// IsExpired will returned the expired state of the currently cached provider
// if there is one. If there is no current provider, true will be returned.
func (c *ChainProvider) IsExpired() bool {
if c.curr != nil {
return c.curr.IsExpired()
}
return true
}

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// Package credentials provides credential retrieval and management
//
// The Credentials is the primary method of getting access to and managing
// credentials Values. Using dependency injection retrieval of the credential
// values is handled by a object which satisfies the Provider interface.
//
// By default the Credentials.Get() will cache the successful result of a
// Provider's Retrieve() until Provider.IsExpired() returns true. At which
// point Credentials will call Provider's Retrieve() to get new credential Value.
//
// The Provider is responsible for determining when credentials Value have expired.
// It is also important to note that Credentials will always call Retrieve the
// first time Credentials.Get() is called.
//
// Example of using the environment variable credentials.
//
// creds := NewEnvCredentials()
//
// // Retrieve the credentials value
// credValue, err := creds.Get()
// if err != nil {
// // handle error
// }
//
// Example of forcing credentials to expire and be refreshed on the next Get().
// This may be helpful to proactively expire credentials and refresh them sooner
// than they would naturally expire on their own.
//
// creds := NewCredentials(&EC2RoleProvider{})
// creds.Expire()
// credsValue, err := creds.Get()
// // New credentials will be retrieved instead of from cache.
//
//
// Custom Provider
//
// Each Provider built into this package also provides a helper method to generate
// a Credentials pointer setup with the provider. To use a custom Provider just
// create a type which satisfies the Provider interface and pass it to the
// NewCredentials method.
//
// type MyProvider struct{}
// func (m *MyProvider) Retrieve() (Value, error) {...}
// func (m *MyProvider) IsExpired() bool {...}
//
// creds := NewCredentials(&MyProvider{})
// credValue, err := creds.Get()
//
package credentials
import (
"sync"
"time"
)
// AnonymousCredentials is an empty Credential object that can be used as
// dummy placeholder credentials for requests that do not need signed.
//
// This Credentials can be used to configure a service to not sign requests
// when making service API calls. For example, when accessing public
// s3 buckets.
//
// svc := s3.New(&aws.Config{Credentials: AnonymousCredentials})
// // Access public S3 buckets.
//
// @readonly
var AnonymousCredentials = NewStaticCredentials("", "", "")
// A Value is the AWS credentials value for individual credential fields.
type Value struct {
// AWS Access key ID
AccessKeyID string
// AWS Secret Access Key
SecretAccessKey string
// AWS Session Token
SessionToken string
// Provider used to get credentials
ProviderName string
}
// A Provider is the interface for any component which will provide credentials
// Value. A provider is required to manage its own Expired state, and what to
// be expired means.
//
// The Provider should not need to implement its own mutexes, because
// that will be managed by Credentials.
type Provider interface {
// Refresh returns nil if it successfully retrieved the value.
// Error is returned if the value were not obtainable, or empty.
Retrieve() (Value, error)
// IsExpired returns if the credentials are no longer valid, and need
// to be retrieved.
IsExpired() bool
}
// A Expiry provides shared expiration logic to be used by credentials
// providers to implement expiry functionality.
//
// The best method to use this struct is as an anonymous field within the
// provider's struct.
//
// Example:
// type EC2RoleProvider struct {
// Expiry
// ...
// }
type Expiry struct {
// The date/time when to expire on
expiration time.Time
// If set will be used by IsExpired to determine the current time.
// Defaults to time.Now if CurrentTime is not set. Available for testing
// to be able to mock out the current time.
CurrentTime func() time.Time
}
// SetExpiration sets the expiration IsExpired will check when called.
//
// If window is greater than 0 the expiration time will be reduced by the
// window value.
//
// Using a window is helpful to trigger credentials to expire sooner than
// the expiration time given to ensure no requests are made with expired
// tokens.
func (e *Expiry) SetExpiration(expiration time.Time, window time.Duration) {
e.expiration = expiration
if window > 0 {
e.expiration = e.expiration.Add(-window)
}
}
// IsExpired returns if the credentials are expired.
func (e *Expiry) IsExpired() bool {
if e.CurrentTime == nil {
e.CurrentTime = time.Now
}
return e.expiration.Before(e.CurrentTime())
}
// A Credentials provides synchronous safe retrieval of AWS credentials Value.
// Credentials will cache the credentials value until they expire. Once the value
// expires the next Get will attempt to retrieve valid credentials.
//
// Credentials is safe to use across multiple goroutines and will manage the
// synchronous state so the Providers do not need to implement their own
// synchronization.
//
// The first Credentials.Get() will always call Provider.Retrieve() to get the
// first instance of the credentials Value. All calls to Get() after that
// will return the cached credentials Value until IsExpired() returns true.
type Credentials struct {
creds Value
forceRefresh bool
m sync.Mutex
provider Provider
}
// NewCredentials returns a pointer to a new Credentials with the provider set.
func NewCredentials(provider Provider) *Credentials {
return &Credentials{
provider: provider,
forceRefresh: true,
}
}
// Get returns the credentials value, or error if the credentials Value failed
// to be retrieved.
//
// Will return the cached credentials Value if it has not expired. If the
// credentials Value has expired the Provider's Retrieve() will be called
// to refresh the credentials.
//
// If Credentials.Expire() was called the credentials Value will be force
// expired, and the next call to Get() will cause them to be refreshed.
func (c *Credentials) Get() (Value, error) {
c.m.Lock()
defer c.m.Unlock()
if c.isExpired() {
creds, err := c.provider.Retrieve()
if err != nil {
return Value{}, err
}
c.creds = creds
c.forceRefresh = false
}
return c.creds, nil
}
// Expire expires the credentials and forces them to be retrieved on the
// next call to Get().
//
// This will override the Provider's expired state, and force Credentials
// to call the Provider's Retrieve().
func (c *Credentials) Expire() {
c.m.Lock()
defer c.m.Unlock()
c.forceRefresh = true
}
// IsExpired returns if the credentials are no longer valid, and need
// to be retrieved.
//
// If the Credentials were forced to be expired with Expire() this will
// reflect that override.
func (c *Credentials) IsExpired() bool {
c.m.Lock()
defer c.m.Unlock()
return c.isExpired()
}
// isExpired helper method wrapping the definition of expired credentials.
func (c *Credentials) isExpired() bool {
return c.forceRefresh || c.provider.IsExpired()
}

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package ec2rolecreds
import (
"bufio"
"encoding/json"
"fmt"
"path"
"strings"
"time"
"github.com/aws/aws-sdk-go/aws/awserr"
"github.com/aws/aws-sdk-go/aws/client"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/aws/ec2metadata"
)
// ProviderName provides a name of EC2Role provider
const ProviderName = "EC2RoleProvider"
// A EC2RoleProvider retrieves credentials from the EC2 service, and keeps track if
// those credentials are expired.
//
// Example how to configure the EC2RoleProvider with custom http Client, Endpoint
// or ExpiryWindow
//
// p := &ec2rolecreds.EC2RoleProvider{
// // Pass in a custom timeout to be used when requesting
// // IAM EC2 Role credentials.
// Client: ec2metadata.New(sess, aws.Config{
// HTTPClient: &http.Client{Timeout: 10 * time.Second},
// }),
//
// // Do not use early expiry of credentials. If a non zero value is
// // specified the credentials will be expired early
// ExpiryWindow: 0,
// }
type EC2RoleProvider struct {
credentials.Expiry
// Required EC2Metadata client to use when connecting to EC2 metadata service.
Client *ec2metadata.EC2Metadata
// ExpiryWindow will allow the credentials to trigger refreshing prior to
// the credentials actually expiring. This is beneficial so race conditions
// with expiring credentials do not cause request to fail unexpectedly
// due to ExpiredTokenException exceptions.
//
// So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
// 10 seconds before the credentials are actually expired.
//
// If ExpiryWindow is 0 or less it will be ignored.
ExpiryWindow time.Duration
}
// NewCredentials returns a pointer to a new Credentials object wrapping
// the EC2RoleProvider. Takes a ConfigProvider to create a EC2Metadata client.
// The ConfigProvider is satisfied by the session.Session type.
func NewCredentials(c client.ConfigProvider, options ...func(*EC2RoleProvider)) *credentials.Credentials {
p := &EC2RoleProvider{
Client: ec2metadata.New(c),
}
for _, option := range options {
option(p)
}
return credentials.NewCredentials(p)
}
// NewCredentialsWithClient returns a pointer to a new Credentials object wrapping
// the EC2RoleProvider. Takes a EC2Metadata client to use when connecting to EC2
// metadata service.
func NewCredentialsWithClient(client *ec2metadata.EC2Metadata, options ...func(*EC2RoleProvider)) *credentials.Credentials {
p := &EC2RoleProvider{
Client: client,
}
for _, option := range options {
option(p)
}
return credentials.NewCredentials(p)
}
// Retrieve retrieves credentials from the EC2 service.
// Error will be returned if the request fails, or unable to extract
// the desired credentials.
func (m *EC2RoleProvider) Retrieve() (credentials.Value, error) {
credsList, err := requestCredList(m.Client)
if err != nil {
return credentials.Value{ProviderName: ProviderName}, err
}
if len(credsList) == 0 {
return credentials.Value{ProviderName: ProviderName}, awserr.New("EmptyEC2RoleList", "empty EC2 Role list", nil)
}
credsName := credsList[0]
roleCreds, err := requestCred(m.Client, credsName)
if err != nil {
return credentials.Value{ProviderName: ProviderName}, err
}
m.SetExpiration(roleCreds.Expiration, m.ExpiryWindow)
return credentials.Value{
AccessKeyID: roleCreds.AccessKeyID,
SecretAccessKey: roleCreds.SecretAccessKey,
SessionToken: roleCreds.Token,
ProviderName: ProviderName,
}, nil
}
// A ec2RoleCredRespBody provides the shape for unmarshaling credential
// request responses.
type ec2RoleCredRespBody struct {
// Success State
Expiration time.Time
AccessKeyID string
SecretAccessKey string
Token string
// Error state
Code string
Message string
}
const iamSecurityCredsPath = "/iam/security-credentials"
// requestCredList requests a list of credentials from the EC2 service.
// If there are no credentials, or there is an error making or receiving the request
func requestCredList(client *ec2metadata.EC2Metadata) ([]string, error) {
resp, err := client.GetMetadata(iamSecurityCredsPath)
if err != nil {
return nil, awserr.New("EC2RoleRequestError", "no EC2 instance role found", err)
}
credsList := []string{}
s := bufio.NewScanner(strings.NewReader(resp))
for s.Scan() {
credsList = append(credsList, s.Text())
}
if err := s.Err(); err != nil {
return nil, awserr.New("SerializationError", "failed to read EC2 instance role from metadata service", err)
}
return credsList, nil
}
// requestCred requests the credentials for a specific credentials from the EC2 service.
//
// If the credentials cannot be found, or there is an error reading the response
// and error will be returned.
func requestCred(client *ec2metadata.EC2Metadata, credsName string) (ec2RoleCredRespBody, error) {
resp, err := client.GetMetadata(path.Join(iamSecurityCredsPath, credsName))
if err != nil {
return ec2RoleCredRespBody{},
awserr.New("EC2RoleRequestError",
fmt.Sprintf("failed to get %s EC2 instance role credentials", credsName),
err)
}
respCreds := ec2RoleCredRespBody{}
if err := json.NewDecoder(strings.NewReader(resp)).Decode(&respCreds); err != nil {
return ec2RoleCredRespBody{},
awserr.New("SerializationError",
fmt.Sprintf("failed to decode %s EC2 instance role credentials", credsName),
err)
}
if respCreds.Code != "Success" {
// If an error code was returned something failed requesting the role.
return ec2RoleCredRespBody{}, awserr.New(respCreds.Code, respCreds.Message, nil)
}
return respCreds, nil
}

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// Package endpointcreds provides support for retrieving credentials from an
// arbitrary HTTP endpoint.
//
// The credentials endpoint Provider can receive both static and refreshable
// credentials that will expire. Credentials are static when an "Expiration"
// value is not provided in the endpoint's response.
//
// Static credentials will never expire once they have been retrieved. The format
// of the static credentials response:
// {
// "AccessKeyId" : "MUA...",
// "SecretAccessKey" : "/7PC5om....",
// }
//
// Refreshable credentials will expire within the "ExpiryWindow" of the Expiration
// value in the response. The format of the refreshable credentials response:
// {
// "AccessKeyId" : "MUA...",
// "SecretAccessKey" : "/7PC5om....",
// "Token" : "AQoDY....=",
// "Expiration" : "2016-02-25T06:03:31Z"
// }
//
// Errors should be returned in the following format and only returned with 400
// or 500 HTTP status codes.
// {
// "code": "ErrorCode",
// "message": "Helpful error message."
// }
package endpointcreds
import (
"encoding/json"
"time"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/awserr"
"github.com/aws/aws-sdk-go/aws/client"
"github.com/aws/aws-sdk-go/aws/client/metadata"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/aws/request"
)
// ProviderName is the name of the credentials provider.
const ProviderName = `CredentialsEndpointProvider`
// Provider satisfies the credentials.Provider interface, and is a client to
// retrieve credentials from an arbitrary endpoint.
type Provider struct {
staticCreds bool
credentials.Expiry
// Requires a AWS Client to make HTTP requests to the endpoint with.
// the Endpoint the request will be made to is provided by the aws.Config's
// Endpoint value.
Client *client.Client
// ExpiryWindow will allow the credentials to trigger refreshing prior to
// the credentials actually expiring. This is beneficial so race conditions
// with expiring credentials do not cause request to fail unexpectedly
// due to ExpiredTokenException exceptions.
//
// So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
// 10 seconds before the credentials are actually expired.
//
// If ExpiryWindow is 0 or less it will be ignored.
ExpiryWindow time.Duration
}
// NewProviderClient returns a credentials Provider for retrieving AWS credentials
// from arbitrary endpoint.
func NewProviderClient(cfg aws.Config, handlers request.Handlers, endpoint string, options ...func(*Provider)) credentials.Provider {
p := &Provider{
Client: client.New(
cfg,
metadata.ClientInfo{
ServiceName: "CredentialsEndpoint",
Endpoint: endpoint,
},
handlers,
),
}
p.Client.Handlers.Unmarshal.PushBack(unmarshalHandler)
p.Client.Handlers.UnmarshalError.PushBack(unmarshalError)
p.Client.Handlers.Validate.Clear()
p.Client.Handlers.Validate.PushBack(validateEndpointHandler)
for _, option := range options {
option(p)
}
return p
}
// NewCredentialsClient returns a Credentials wrapper for retrieving credentials
// from an arbitrary endpoint concurrently. The client will request the
func NewCredentialsClient(cfg aws.Config, handlers request.Handlers, endpoint string, options ...func(*Provider)) *credentials.Credentials {
return credentials.NewCredentials(NewProviderClient(cfg, handlers, endpoint, options...))
}
// IsExpired returns true if the credentials retrieved are expired, or not yet
// retrieved.
func (p *Provider) IsExpired() bool {
if p.staticCreds {
return false
}
return p.Expiry.IsExpired()
}
// Retrieve will attempt to request the credentials from the endpoint the Provider
// was configured for. And error will be returned if the retrieval fails.
func (p *Provider) Retrieve() (credentials.Value, error) {
resp, err := p.getCredentials()
if err != nil {
return credentials.Value{ProviderName: ProviderName},
awserr.New("CredentialsEndpointError", "failed to load credentials", err)
}
if resp.Expiration != nil {
p.SetExpiration(*resp.Expiration, p.ExpiryWindow)
} else {
p.staticCreds = true
}
return credentials.Value{
AccessKeyID: resp.AccessKeyID,
SecretAccessKey: resp.SecretAccessKey,
SessionToken: resp.Token,
ProviderName: ProviderName,
}, nil
}
type getCredentialsOutput struct {
Expiration *time.Time
AccessKeyID string
SecretAccessKey string
Token string
}
type errorOutput struct {
Code string `json:"code"`
Message string `json:"message"`
}
func (p *Provider) getCredentials() (*getCredentialsOutput, error) {
op := &request.Operation{
Name: "GetCredentials",
HTTPMethod: "GET",
}
out := &getCredentialsOutput{}
req := p.Client.NewRequest(op, nil, out)
req.HTTPRequest.Header.Set("Accept", "application/json")
return out, req.Send()
}
func validateEndpointHandler(r *request.Request) {
if len(r.ClientInfo.Endpoint) == 0 {
r.Error = aws.ErrMissingEndpoint
}
}
func unmarshalHandler(r *request.Request) {
defer r.HTTPResponse.Body.Close()
out := r.Data.(*getCredentialsOutput)
if err := json.NewDecoder(r.HTTPResponse.Body).Decode(&out); err != nil {
r.Error = awserr.New("SerializationError",
"failed to decode endpoint credentials",
err,
)
}
}
func unmarshalError(r *request.Request) {
defer r.HTTPResponse.Body.Close()
var errOut errorOutput
if err := json.NewDecoder(r.HTTPResponse.Body).Decode(&errOut); err != nil {
r.Error = awserr.New("SerializationError",
"failed to decode endpoint credentials",
err,
)
}
// Response body format is not consistent between metadata endpoints.
// Grab the error message as a string and include that as the source error
r.Error = awserr.New(errOut.Code, errOut.Message, nil)
}

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package credentials
import (
"os"
"github.com/aws/aws-sdk-go/aws/awserr"
)
// EnvProviderName provides a name of Env provider
const EnvProviderName = "EnvProvider"
var (
// ErrAccessKeyIDNotFound is returned when the AWS Access Key ID can't be
// found in the process's environment.
//
// @readonly
ErrAccessKeyIDNotFound = awserr.New("EnvAccessKeyNotFound", "AWS_ACCESS_KEY_ID or AWS_ACCESS_KEY not found in environment", nil)
// ErrSecretAccessKeyNotFound is returned when the AWS Secret Access Key
// can't be found in the process's environment.
//
// @readonly
ErrSecretAccessKeyNotFound = awserr.New("EnvSecretNotFound", "AWS_SECRET_ACCESS_KEY or AWS_SECRET_KEY not found in environment", nil)
)
// A EnvProvider retrieves credentials from the environment variables of the
// running process. Environment credentials never expire.
//
// Environment variables used:
//
// * Access Key ID: AWS_ACCESS_KEY_ID or AWS_ACCESS_KEY
// * Secret Access Key: AWS_SECRET_ACCESS_KEY or AWS_SECRET_KEY
type EnvProvider struct {
retrieved bool
}
// NewEnvCredentials returns a pointer to a new Credentials object
// wrapping the environment variable provider.
func NewEnvCredentials() *Credentials {
return NewCredentials(&EnvProvider{})
}
// Retrieve retrieves the keys from the environment.
func (e *EnvProvider) Retrieve() (Value, error) {
e.retrieved = false
id := os.Getenv("AWS_ACCESS_KEY_ID")
if id == "" {
id = os.Getenv("AWS_ACCESS_KEY")
}
secret := os.Getenv("AWS_SECRET_ACCESS_KEY")
if secret == "" {
secret = os.Getenv("AWS_SECRET_KEY")
}
if id == "" {
return Value{ProviderName: EnvProviderName}, ErrAccessKeyIDNotFound
}
if secret == "" {
return Value{ProviderName: EnvProviderName}, ErrSecretAccessKeyNotFound
}
e.retrieved = true
return Value{
AccessKeyID: id,
SecretAccessKey: secret,
SessionToken: os.Getenv("AWS_SESSION_TOKEN"),
ProviderName: EnvProviderName,
}, nil
}
// IsExpired returns if the credentials have been retrieved.
func (e *EnvProvider) IsExpired() bool {
return !e.retrieved
}

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package credentials
import (
"fmt"
"os"
"path/filepath"
"github.com/go-ini/ini"
"github.com/aws/aws-sdk-go/aws/awserr"
)
// SharedCredsProviderName provides a name of SharedCreds provider
const SharedCredsProviderName = "SharedCredentialsProvider"
var (
// ErrSharedCredentialsHomeNotFound is emitted when the user directory cannot be found.
//
// @readonly
ErrSharedCredentialsHomeNotFound = awserr.New("UserHomeNotFound", "user home directory not found.", nil)
)
// A SharedCredentialsProvider retrieves credentials from the current user's home
// directory, and keeps track if those credentials are expired.
//
// Profile ini file example: $HOME/.aws/credentials
type SharedCredentialsProvider struct {
// Path to the shared credentials file.
//
// If empty will look for "AWS_SHARED_CREDENTIALS_FILE" env variable. If the
// env value is empty will default to current user's home directory.
// Linux/OSX: "$HOME/.aws/credentials"
// Windows: "%USERPROFILE%\.aws\credentials"
Filename string
// AWS Profile to extract credentials from the shared credentials file. If empty
// will default to environment variable "AWS_PROFILE" or "default" if
// environment variable is also not set.
Profile string
// retrieved states if the credentials have been successfully retrieved.
retrieved bool
}
// NewSharedCredentials returns a pointer to a new Credentials object
// wrapping the Profile file provider.
func NewSharedCredentials(filename, profile string) *Credentials {
return NewCredentials(&SharedCredentialsProvider{
Filename: filename,
Profile: profile,
})
}
// Retrieve reads and extracts the shared credentials from the current
// users home directory.
func (p *SharedCredentialsProvider) Retrieve() (Value, error) {
p.retrieved = false
filename, err := p.filename()
if err != nil {
return Value{ProviderName: SharedCredsProviderName}, err
}
creds, err := loadProfile(filename, p.profile())
if err != nil {
return Value{ProviderName: SharedCredsProviderName}, err
}
p.retrieved = true
return creds, nil
}
// IsExpired returns if the shared credentials have expired.
func (p *SharedCredentialsProvider) IsExpired() bool {
return !p.retrieved
}
// loadProfiles loads from the file pointed to by shared credentials filename for profile.
// The credentials retrieved from the profile will be returned or error. Error will be
// returned if it fails to read from the file, or the data is invalid.
func loadProfile(filename, profile string) (Value, error) {
config, err := ini.Load(filename)
if err != nil {
return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsLoad", "failed to load shared credentials file", err)
}
iniProfile, err := config.GetSection(profile)
if err != nil {
return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsLoad", "failed to get profile", err)
}
id, err := iniProfile.GetKey("aws_access_key_id")
if err != nil {
return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsAccessKey",
fmt.Sprintf("shared credentials %s in %s did not contain aws_access_key_id", profile, filename),
err)
}
secret, err := iniProfile.GetKey("aws_secret_access_key")
if err != nil {
return Value{ProviderName: SharedCredsProviderName}, awserr.New("SharedCredsSecret",
fmt.Sprintf("shared credentials %s in %s did not contain aws_secret_access_key", profile, filename),
nil)
}
// Default to empty string if not found
token := iniProfile.Key("aws_session_token")
return Value{
AccessKeyID: id.String(),
SecretAccessKey: secret.String(),
SessionToken: token.String(),
ProviderName: SharedCredsProviderName,
}, nil
}
// filename returns the filename to use to read AWS shared credentials.
//
// Will return an error if the user's home directory path cannot be found.
func (p *SharedCredentialsProvider) filename() (string, error) {
if p.Filename == "" {
if p.Filename = os.Getenv("AWS_SHARED_CREDENTIALS_FILE"); p.Filename != "" {
return p.Filename, nil
}
homeDir := os.Getenv("HOME") // *nix
if homeDir == "" { // Windows
homeDir = os.Getenv("USERPROFILE")
}
if homeDir == "" {
return "", ErrSharedCredentialsHomeNotFound
}
p.Filename = filepath.Join(homeDir, ".aws", "credentials")
}
return p.Filename, nil
}
// profile returns the AWS shared credentials profile. If empty will read
// environment variable "AWS_PROFILE". If that is not set profile will
// return "default".
func (p *SharedCredentialsProvider) profile() string {
if p.Profile == "" {
p.Profile = os.Getenv("AWS_PROFILE")
}
if p.Profile == "" {
p.Profile = "default"
}
return p.Profile
}

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@ -0,0 +1,57 @@
package credentials
import (
"github.com/aws/aws-sdk-go/aws/awserr"
)
// StaticProviderName provides a name of Static provider
const StaticProviderName = "StaticProvider"
var (
// ErrStaticCredentialsEmpty is emitted when static credentials are empty.
//
// @readonly
ErrStaticCredentialsEmpty = awserr.New("EmptyStaticCreds", "static credentials are empty", nil)
)
// A StaticProvider is a set of credentials which are set programmatically,
// and will never expire.
type StaticProvider struct {
Value
}
// NewStaticCredentials returns a pointer to a new Credentials object
// wrapping a static credentials value provider.
func NewStaticCredentials(id, secret, token string) *Credentials {
return NewCredentials(&StaticProvider{Value: Value{
AccessKeyID: id,
SecretAccessKey: secret,
SessionToken: token,
}})
}
// NewStaticCredentialsFromCreds returns a pointer to a new Credentials object
// wrapping the static credentials value provide. Same as NewStaticCredentials
// but takes the creds Value instead of individual fields
func NewStaticCredentialsFromCreds(creds Value) *Credentials {
return NewCredentials(&StaticProvider{Value: creds})
}
// Retrieve returns the credentials or error if the credentials are invalid.
func (s *StaticProvider) Retrieve() (Value, error) {
if s.AccessKeyID == "" || s.SecretAccessKey == "" {
return Value{ProviderName: StaticProviderName}, ErrStaticCredentialsEmpty
}
if len(s.Value.ProviderName) == 0 {
s.Value.ProviderName = StaticProviderName
}
return s.Value, nil
}
// IsExpired returns if the credentials are expired.
//
// For StaticProvider, the credentials never expired.
func (s *StaticProvider) IsExpired() bool {
return false
}

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// Package stscreds are credential Providers to retrieve STS AWS credentials.
//
// STS provides multiple ways to retrieve credentials which can be used when making
// future AWS service API operation calls.
package stscreds
import (
"fmt"
"time"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/client"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/service/sts"
)
// ProviderName provides a name of AssumeRole provider
const ProviderName = "AssumeRoleProvider"
// AssumeRoler represents the minimal subset of the STS client API used by this provider.
type AssumeRoler interface {
AssumeRole(input *sts.AssumeRoleInput) (*sts.AssumeRoleOutput, error)
}
// DefaultDuration is the default amount of time in minutes that the credentials
// will be valid for.
var DefaultDuration = time.Duration(15) * time.Minute
// AssumeRoleProvider retrieves temporary credentials from the STS service, and
// keeps track of their expiration time. This provider must be used explicitly,
// as it is not included in the credentials chain.
type AssumeRoleProvider struct {
credentials.Expiry
// STS client to make assume role request with.
Client AssumeRoler
// Role to be assumed.
RoleARN string
// Session name, if you wish to reuse the credentials elsewhere.
RoleSessionName string
// Expiry duration of the STS credentials. Defaults to 15 minutes if not set.
Duration time.Duration
// Optional ExternalID to pass along, defaults to nil if not set.
ExternalID *string
// The policy plain text must be 2048 bytes or shorter. However, an internal
// conversion compresses it into a packed binary format with a separate limit.
// The PackedPolicySize response element indicates by percentage how close to
// the upper size limit the policy is, with 100% equaling the maximum allowed
// size.
Policy *string
// The identification number of the MFA device that is associated with the user
// who is making the AssumeRole call. Specify this value if the trust policy
// of the role being assumed includes a condition that requires MFA authentication.
// The value is either the serial number for a hardware device (such as GAHT12345678)
// or an Amazon Resource Name (ARN) for a virtual device (such as arn:aws:iam::123456789012:mfa/user).
SerialNumber *string
// The value provided by the MFA device, if the trust policy of the role being
// assumed requires MFA (that is, if the policy includes a condition that tests
// for MFA). If the role being assumed requires MFA and if the TokenCode value
// is missing or expired, the AssumeRole call returns an "access denied" error.
TokenCode *string
// ExpiryWindow will allow the credentials to trigger refreshing prior to
// the credentials actually expiring. This is beneficial so race conditions
// with expiring credentials do not cause request to fail unexpectedly
// due to ExpiredTokenException exceptions.
//
// So a ExpiryWindow of 10s would cause calls to IsExpired() to return true
// 10 seconds before the credentials are actually expired.
//
// If ExpiryWindow is 0 or less it will be ignored.
ExpiryWindow time.Duration
}
// NewCredentials returns a pointer to a new Credentials object wrapping the
// AssumeRoleProvider. The credentials will expire every 15 minutes and the
// role will be named after a nanosecond timestamp of this operation.
//
// Takes a Config provider to create the STS client. The ConfigProvider is
// satisfied by the session.Session type.
func NewCredentials(c client.ConfigProvider, roleARN string, options ...func(*AssumeRoleProvider)) *credentials.Credentials {
p := &AssumeRoleProvider{
Client: sts.New(c),
RoleARN: roleARN,
Duration: DefaultDuration,
}
for _, option := range options {
option(p)
}
return credentials.NewCredentials(p)
}
// NewCredentialsWithClient returns a pointer to a new Credentials object wrapping the
// AssumeRoleProvider. The credentials will expire every 15 minutes and the
// role will be named after a nanosecond timestamp of this operation.
//
// Takes an AssumeRoler which can be satisfiede by the STS client.
func NewCredentialsWithClient(svc AssumeRoler, roleARN string, options ...func(*AssumeRoleProvider)) *credentials.Credentials {
p := &AssumeRoleProvider{
Client: svc,
RoleARN: roleARN,
Duration: DefaultDuration,
}
for _, option := range options {
option(p)
}
return credentials.NewCredentials(p)
}
// Retrieve generates a new set of temporary credentials using STS.
func (p *AssumeRoleProvider) Retrieve() (credentials.Value, error) {
// Apply defaults where parameters are not set.
if p.RoleSessionName == "" {
// Try to work out a role name that will hopefully end up unique.
p.RoleSessionName = fmt.Sprintf("%d", time.Now().UTC().UnixNano())
}
if p.Duration == 0 {
// Expire as often as AWS permits.
p.Duration = DefaultDuration
}
input := &sts.AssumeRoleInput{
DurationSeconds: aws.Int64(int64(p.Duration / time.Second)),
RoleArn: aws.String(p.RoleARN),
RoleSessionName: aws.String(p.RoleSessionName),
ExternalId: p.ExternalID,
}
if p.Policy != nil {
input.Policy = p.Policy
}
if p.SerialNumber != nil && p.TokenCode != nil {
input.SerialNumber = p.SerialNumber
input.TokenCode = p.TokenCode
}
roleOutput, err := p.Client.AssumeRole(input)
if err != nil {
return credentials.Value{ProviderName: ProviderName}, err
}
// We will proactively generate new credentials before they expire.
p.SetExpiration(*roleOutput.Credentials.Expiration, p.ExpiryWindow)
return credentials.Value{
AccessKeyID: *roleOutput.Credentials.AccessKeyId,
SecretAccessKey: *roleOutput.Credentials.SecretAccessKey,
SessionToken: *roleOutput.Credentials.SessionToken,
ProviderName: ProviderName,
}, nil
}