[MetricBeat] add param aws_partition to support aws-cn, aws-us-gov …

…regions (elastic#19423)

* add params `aws_partition` to support other aws region: aws-cn, aws-us-gov

CHANGELOG.next.asciidoc

@@ -258,6 +258,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Fix incorrect usage of hints builder when exposed port is a substring of the hint {pull}19052[19052]
 - Remove dedot for tag values in aws module. {issue}19112[19112] {pull}19221[19221]
 - Stop counterCache only when already started {pull}19103[19103]
+- Add param `aws_partition` to support aws-cn, aws-us-gov regions. {issue}18850[18850] {pull}19423[19423]
 - Fix bug incorrect parsing of float numbers as integers in Couchbase module {issue}18949[18949] {pull}19055[19055]
 
 *Packetbeat*

x-pack/libbeat/common/aws/credentials.go

@@ -24,6 +24,7 @@ type ConfigAWS struct {
  SharedCredentialFile string `config:"shared_credential_file"`
  Endpoint string `config:"endpoint"`
  RoleArn string `config:"role_arn"`
+ AWSPartition string `config:"aws_partition"`
 }
 
 // GetAWSCredentials function gets aws credentials from the config.

x-pack/libbeat/docs/aws-credentials-config.asciidoc

@@ -11,6 +11,7 @@ To configure AWS credentials, either put the credentials into the {beatname_uc}
 * *shared_credential_file*: directory of the shared credentials file.
 * *endpoint*: URL of the entry point for an AWS web service.
 * *role_arn*: AWS IAM Role to assume.
+* *aws_partition*: AWS region parttion name, value is one of `aws, aws-cn, aws-us-gov`, default is `aws`.
 
 [float]
 ==== Supported Formats

x-pack/metricbeat/module/aws/aws.go

@@ -93,8 +93,16 @@ func NewMetricSet(base mb.BaseMetricSet) (*MetricSet, error) {
  base.Logger().Debug("Metricset level config for period: ", metricSet.Period)
  base.Logger().Debug("Metricset level config for tags filter: ", metricSet.TagsFilter)
 
- // Get IAM account name
- awsConfig.Region = "us-east-1"
+ // Get IAM account name, set region by aws_partition, default is aws global partition
+ // refer https://docs.aws.amazon.com/general/latest/gr/aws-arns-and-namespaces.html
+ switch config.AWSConfig.AWSPartition {
+ case "aws-cn":
+ awsConfig.Region = "cn-north-1"
+ case "aws-us-gov":
+ awsConfig.Region = "us-gov-east-1"
+ default:
+ awsConfig.Region = "us-east-1"
+ }
  svcIam := iam.New(awscommon.EnrichAWSConfigWithEndpoint(
  config.AWSConfig.Endpoint, "iam", "", awsConfig))
  req := svcIam.ListAccountAliasesRequest(&iam.ListAccountAliasesInput{})