package session
import (
"os"
"strconv"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/aws/defaults"
)
// EnvProviderName provides a name of the provider when config is loaded from environment.
const EnvProviderName = "EnvConfigCredentials"
// envConfig is a collection of environment values the SDK will read
// setup config from. All environment values are optional. But some values
// such as credentials require multiple values to be complete or the values
// will be ignored.
type envConfig struct {
// Environment configuration values. If set both Access Key ID and Secret Access
// Key must be provided. Session Token and optionally also be provided, but is
// not required.
//
// # Access Key ID
// AWS_ACCESS_KEY_ID=AKID
// AWS_ACCESS_KEY=AKID # only read if AWS_ACCESS_KEY_ID is not set.
//
// # Secret Access Key
// AWS_SECRET_ACCESS_KEY=SECRET
// AWS_SECRET_KEY=SECRET=SECRET # only read if AWS_SECRET_ACCESS_KEY is not set.
//
// # Session Token
// AWS_SESSION_TOKEN=TOKEN
Creds credentials.Value
// Region value will instruct the SDK where to make service API requests to. If is
// not provided in the environment the region must be provided before a service
// client request is made.
//
// AWS_REGION=us-east-1
//
// # AWS_DEFAULT_REGION is only read if AWS_SDK_LOAD_CONFIG is also set,
// # and AWS_REGION is not also set.
// AWS_DEFAULT_REGION=us-east-1
Region string
// Profile name the SDK should load use when loading shared configuration from the
// shared configuration files. If not provided "default" will be used as the
// profile name.
//
// AWS_PROFILE=my_profile
//
// # AWS_DEFAULT_PROFILE is only read if AWS_SDK_LOAD_CONFIG is also set,
// # and AWS_PROFILE is not also set.
// AWS_DEFAULT_PROFILE=my_profile
Profile string
// SDK load config instructs the SDK to load the shared config in addition to
// shared credentials. This also expands the configuration loaded from the shared
// credentials to have parity with the shared config file. This also enables
// Region and Profile support for the AWS_DEFAULT_REGION and AWS_DEFAULT_PROFILE
// env values as well.
//
// AWS_SDK_LOAD_CONFIG=1
EnableSharedConfig bool
// Shared credentials file path can be set to instruct the SDK to use an alternate
// file for the shared credentials. If not set the file will be loaded from
// $HOME/.aws/credentials on Linux/Unix based systems, and
// %USERPROFILE%\.aws\credentials on Windows.
//
// AWS_SHARED_CREDENTIALS_FILE=$HOME/my_shared_credentials
SharedCredentialsFile string
// Shared config file path can be set to instruct the SDK to use an alternate
// file for the shared config. If not set the file will be loaded from
// $HOME/.aws/config on Linux/Unix based systems, and
// %USERPROFILE%\.aws\config on Windows.
//
// AWS_CONFIG_FILE=$HOME/my_shared_config
SharedConfigFile string
// Sets the path to a custom Credentials Authority (CA) Bundle PEM file
// that the SDK will use instead of the system's root CA bundle.
// Only use this if you want to configure the SDK to use a custom set
// of CAs.
//
// Enabling this option will attempt to merge the Transport
// into the SDK's HTTP client. If the client's Transport is
// not a http.Transport an error will be returned. If the
// Transport's TLS config is set this option will cause the
// SDK to overwrite the Transport's TLS config's RootCAs value.
//
// Setting a custom HTTPClient in the aws.Config options will override this setting.
// To use this option and custom HTTP client, the HTTP client needs to be provided
// when creating the session. Not the service client.
//
// AWS_CA_BUNDLE=$HOME/my_custom_ca_bundle
CustomCABundle string
csmEnabled string
CSMEnabled bool
CSMPort string
CSMClientID string
CSMHost string
// Enables endpoint discovery via environment variables.
//
// AWS_ENABLE_ENDPOINT_DISCOVERY=true
EnableEndpointDiscovery *bool
enableEndpointDiscovery string
// Specifies the WebIdentity token the SDK should use to assume a role
// with.
//
// AWS_WEB_IDENTITY_TOKEN_FILE=file_path
WebIdentityTokenFilePath string
// Specifies the IAM role arn to use when assuming an role.
//
// AWS_ROLE_ARN=role_arn
RoleARN string
// Specifies the IAM role session name to use when assuming a role.
//
// AWS_ROLE_SESSION_NAME=session_name
RoleSessionName string
}
var (
csmEnabledEnvKey = []string{
"AWS_CSM_ENABLED",
}
csmHostEnvKey = []string{
"AWS_CSM_HOST",
}
csmPortEnvKey = []string{
"AWS_CSM_PORT",
}
csmClientIDEnvKey = []string{
"AWS_CSM_CLIENT_ID",
}
credAccessEnvKey = []string{
"AWS_ACCESS_KEY_ID",
"AWS_ACCESS_KEY",
}
credSecretEnvKey = []string{
"AWS_SECRET_ACCESS_KEY",
"AWS_SECRET_KEY",
}
credSessionEnvKey = []string{
"AWS_SESSION_TOKEN",
}
enableEndpointDiscoveryEnvKey = []string{
"AWS_ENABLE_ENDPOINT_DISCOVERY",
}
regionEnvKeys = []string{
"AWS_REGION",
"AWS_DEFAULT_REGION", // Only read if AWS_SDK_LOAD_CONFIG is also set
}
profileEnvKeys = []string{
"AWS_PROFILE",
"AWS_DEFAULT_PROFILE", // Only read if AWS_SDK_LOAD_CONFIG is also set
}
sharedCredsFileEnvKey = []string{
"AWS_SHARED_CREDENTIALS_FILE",
}
sharedConfigFileEnvKey = []string{
"AWS_CONFIG_FILE",
}
webIdentityTokenFilePathEnvKey = []string{
"AWS_WEB_IDENTITY_TOKEN_FILE",
}
roleARNEnvKey = []string{
"AWS_ROLE_ARN",
}
roleSessionNameEnvKey = []string{
"AWS_ROLE_SESSION_NAME",
}
)
// loadEnvConfig retrieves the SDK's environment configuration.
// See `envConfig` for the values that will be retrieved.
//
// If the environment variable `AWS_SDK_LOAD_CONFIG` is set to a truthy value
// the shared SDK config will be loaded in addition to the SDK's specific
// configuration values.
func loadEnvConfig() envConfig {
enableSharedConfig, _ := strconv.ParseBool(os.Getenv("AWS_SDK_LOAD_CONFIG"))
return envConfigLoad(enableSharedConfig)
}
// loadEnvSharedConfig retrieves the SDK's environment configuration, and the
// SDK shared config. See `envConfig` for the values that will be retrieved.
//
// Loads the shared configuration in addition to the SDK's specific configuration.
// This will load the same values as `loadEnvConfig` if the `AWS_SDK_LOAD_CONFIG`
// environment variable is set.
func loadSharedEnvConfig() envConfig {
return envConfigLoad(true)
}
func envConfigLoad(enableSharedConfig bool) envConfig {
cfg := envConfig{}
cfg.EnableSharedConfig = enableSharedConfig
// Static environment credentials
var creds credentials.Value
setFromEnvVal(&creds.AccessKeyID, credAccessEnvKey)
setFromEnvVal(&creds.SecretAccessKey, credSecretEnvKey)
setFromEnvVal(&creds.SessionToken, credSessionEnvKey)
if creds.HasKeys() {
// Require logical grouping of credentials
creds.ProviderName = EnvProviderName
cfg.Creds = creds
}
// Role Metadata
setFromEnvVal(&cfg.RoleARN, roleARNEnvKey)
setFromEnvVal(&cfg.RoleSessionName, roleSessionNameEnvKey)
// Web identity environment variables
setFromEnvVal(&cfg.WebIdentityTokenFilePath, webIdentityTokenFilePathEnvKey)
// CSM environment variables
setFromEnvVal(&cfg.csmEnabled, csmEnabledEnvKey)
setFromEnvVal(&cfg.CSMHost, csmHostEnvKey)
setFromEnvVal(&cfg.CSMPort, csmPortEnvKey)
setFromEnvVal(&cfg.CSMClientID, csmClientIDEnvKey)
cfg.CSMEnabled = len(cfg.csmEnabled) > 0
regionKeys := regionEnvKeys
profileKeys := profileEnvKeys
if !cfg.EnableSharedConfig {
regionKeys = regionKeys[:1]
profileKeys = profileKeys[:1]
}
setFromEnvVal(&cfg.Region, regionKeys)
setFromEnvVal(&cfg.Profile, profileKeys)
// endpoint discovery is in reference to it being enabled.
setFromEnvVal(&cfg.enableEndpointDiscovery, enableEndpointDiscoveryEnvKey)
if len(cfg.enableEndpointDiscovery) > 0 {
cfg.EnableEndpointDiscovery = aws.Bool(cfg.enableEndpointDiscovery != "false")
}
setFromEnvVal(&cfg.SharedCredentialsFile, sharedCredsFileEnvKey)
setFromEnvVal(&cfg.SharedConfigFile, sharedConfigFileEnvKey)
if len(cfg.SharedCredentialsFile) == 0 {
cfg.SharedCredentialsFile = defaults.SharedCredentialsFilename()
}
if len(cfg.SharedConfigFile) == 0 {
cfg.SharedConfigFile = defaults.SharedConfigFilename()
}
cfg.CustomCABundle = os.Getenv("AWS_CA_BUNDLE")
return cfg
}
func setFromEnvVal(dst *string, keys []string) {
for _, k := range keys {
if v := os.Getenv(k); len(v) > 0 {
*dst = v
break
}
}
}
