Added IamRoleRegion to Credential in order to set a custom sts region for sts Client

[foglia-prometeia]

Added iamRoleRegion as attribute in:

• AmazonWebServicesCredentialsBinding.java
  • updated constructor
  • updated assumeRoleProvider --> in buildStsClient now iamRoleRegion attribute is passed as argument
• AWSCredentialsImpl.java
  • updated constructor and overloaded for compatibility
  • updated buildStsClient to include iamRoleRegion as parameter --> clientRegion now dynamically switches to determineClientRegion() if iamRoleRegion is null/empty
  • updated getCredentials() --> updated buildStsClient in order to match the updated method
• credentials.jelly
  • added entry under iamRoleArn for iamRoleRegion as textbox
• Added help-iamRoleRegion.html for help message

GUI Changes

Before

After

Testing done

We created this simple use case:

pipeline {
    agent any
    parameters {
        string(name: 'region', defaultValue: "")
        string(name: 'credential', defaultValue: "")
    }
    stages {
        stage('TEST') {
            steps {
                withCredentials([[
                    $class: 'AmazonWebServicesCredentialsBinding',
                    credentialsId: "${params.credential}",
                    accessKeyVariable: 'AWS_ACCESS_KEY_ID',
                    secretKeyVariable: 'AWS_SECRET_ACCESS_KEY'
                ]]) {
                    sh "aws sts get-caller-identity --region ${params.region}"
                }
            }
        }

    }
}

Problem found before iamRoleRegion
Using the provided test over a credential:role we encountered this error "The security token included in the request is invalid" caused by the role being assumed in a different region then the target region for the aws cli operations.
Thus to solve this problem iamRoleRegion has been added to the plugin Credential.

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