Autoscaler basic auth optional

[asalan316]

The goal of this PR is to make basic authentication when communicating with custom metrics optional.

A new parameter credential_type is introduced as part of the service binding request.
valid values of credential_type are binding-secret and x509

Example Request

cf bind-service <APP_NAME> <AUTOSCLAER_SERVICE_NAME> -c "{ \"credential_type\": \"x509\", \"instance_min_count\": 1, \"instance_max_count\": 4, \"scaling_rules\": [{ \"metric_type\": \"memoryused\", \"breach_duration_secs\": 600, \"threshold\": 30, \"operator\": \"<\", \"cool_down_secs\": 300, \"adjustment\": \"-1\" }] }"

• credential-type = "binding-secret" => allow basic authentication
• credential-type = "x509" => allow mtls authentication only
• no or empty credential-type is provided = > "binding-secret" is the default value

Sample Broker Response Output

# credential-type = "x509"

VCAP_SERVICES: {
    "autoscaler-3044": [
      {
        "binding_guid": "372f14bb-efb3-486c-af81-c41384028d8b",
        "binding_name": null,
        "credentials": {
          "custom_metrics": {
            "mtls_url": "https://autoscaler-3044-metricsforwarder-mtls.autoscaler.app-runtime-interfaces.ci.cloudfoundry.org"
          }
        },..
        ....

# credential-type = "binding-secret"

VCAP_SERVICES: {
    "autoscaler-3044": [
      {
        "binding_guid": "372f14bb-efb3-486c-af81-c41384028d8b",
        "binding_name": null,
        "credentials": {
          "custom_metrics": {
            "mtls_url": "https://autoscaler-3044-metricsforwarder-mtls.autoscaler.app-runtime-interfaces.ci.cloudfoundry.org",
            "username": "XXXXX",
            "password": "XXXXX",
            "url": "https://autoscaler-3044metrics....",
          }
        },

[sonarcloud]

Quality Gate failed

Failed conditions
5.9% Duplication on New Code (required ≤ 3%)

See analysis details on SonarCloud

[asalan316]

ignore url in the json output if zero value for string exist e.g ""