CDS actor support in Policy

Contents

1. Overview of CDS Actor support in Policy

ONAP Policy Framework now enables Controller Design Studio (CDS) as one of the supported actors. This allows the users to configure Operational Policy to use CDS as an actor to remedy a situation.

Behind the scene, when an incoming event is received and validated against rules, Policy uses gRPC to trigger the CBA (Controller Blueprint Archive: CDS artifact) as configured in the operational policy and providing CDS with all the input parameters that is required to execute the chosen CBA.

2. Objective

The goal of the user guide is to clarify the contract between Policy and CDS so that a CBA developer can respect this input contract towards CDS when implementing the CBA.

3. Contract between Policy and CDS

Policy upon receiving an incoming event from DCAE fires the rules and decides which actor to trigger. If the CDS actor is the chosen, Policy triggers the CBA execution using gRPC.

The parameters required for the execution of a CBA are internally handled by Policy. It makes uses of the incoming event, the operational policy configured and AAI lookup to build the CDS request payload.

3.1 CDS Blueprint Execution Payload format as invoked by Policy

Below are the details of the contract established between Policy and CDS to enable the automation of a remediation action within the scope of a closed loop usecase in ONAP.

The format of the input payload for CDS follows the below guidelines, hence a CBA developer must consider this when implementing the CBA logic. For the sake of simplicity a JSON payload is used instead of a gRPC payload and each attribute of the child-nodes is documented.

3.1.1 CommonHeader

The "commonHeader" field in the CBA execute payload is built by policy.

"commonHeader" field name type Description
subRequestId string Generated by Policy. Is a UUID and used internally by policy.
requestId string Inserted by Policy. Maps to the UUID sent by DCAE i.e. the ID used throughout the closed loop lifecycle to identify a request.
originatorId string Generated by Policy and fixed to "POLICY"

3.1.2 ActionIdentifiers

The "actionIdentifiers" field uniquely identifies the CBA and the workflow to execute.

"actionIdentifiers" field name type Description
mode string Inserted by Policy and fixed to "sync" presently.
blueprintName string Inserted by Policy. Maps to the attribute that holds the blueprint-name in the operational policy configuration.
blueprintVersion string Inserted by Policy. Maps to the attribute that holds the blueprint-version in the operational policy configuration.
actionName string Inserted by Policy. Maps to the attribute that holds the action-name in the operational policy configuration.

3.1.3 Payload

The "payload" JSON node is generated by Policy for the action-name specified in the "actionIdentifiers" field which is eventually supplied through the operational policy configuration as indicated above.

3.1.3.1 Action request object

The "$actionName-request" object is generated by CDS for the action-name specified in the "actionIdentifiers" field.

The "$actionName-request" object contains:

  • a field called "resolution-key" which CDS uses to store the resolved parameters into the CDS context
  • a child node object called "$actionName-properties" which holds a map of all the parameters that serve as inputs to the CBA. It presently holds the below information:
    • all the AAI enriched attributes
    • additional parameters embedded in the Control Loop Event format which is sent by DCAE (analytics application).
    • any static information supplied through operational policy configuration which is not specific to an event but applies across all the events.

The data description for the action request object fields is as below:

  • Resolution-key
"$actionName-request" field name type Description
resolution-key string Generated by Policy. Is a UUID, generated each time CBA execute request is invoked.
  • Action properties object
"$actionName-properties" field name type Description
[$aai_node_type.$aai_attribute] map

Inserted by Policy after performing AAI enrichment. Is a map that contains AAI parameters for the target and conforms to the notation: $aai_node_type.$aai_attribute. E.g. for PNF the map looks like below.

{
  "pnf.equip-vendor":"Vendor-A",
  "pnf.ipaddress-v4-oam":"10.10.10.10",
  "pnf.in-maint":false,
  "pnf.pnf-ipv4-address":"3.3.3.3",
  "pnf.resource-version":"1570746989505",
  "pnf.nf-role":"ToR DC101",
  "pnf.equip-type":"Router",
  "pnf.equip-model":"model-123456",
  "pnf.frame-id":"3",
  "pnf.pnf-name":"demo-pnf"
}
data json object OR string Inserted by Policy. Maps to the static payload supplied through operational policy configuration. Used to hold any static information which applies across all the events as described above. If the value of the data field is a valid JSON string it is converted to a JSON object, else will be retained as a string.
[$additionalEventParams] map Inserted by Policy. Maps to the map of additionalEvent parameters embedded into the Control Loop Event message from DCAE.

3.1.4 Summing it up: CBA execute payload generation as done by Policy

Putting all the above information together below is the REST equivalent of the CDS blueprint execute gRPC request generated by Policy.

REST equivalent of the gRPC request from Policy to CDS to execute a CBA.

curl -X POST \
  'http://{{ip}}:{{port}}/api/v1/execution-service/process' \
  -H 'Authorization: Basic Y2NzZGthcHBzOmNjc2RrYXBwcw==' \
  -H 'Content-Type: application/json' \
  -H 'cache-control: no-cache' \
  -d '{
    "commonHeader":{
        "subRequestId":"{generated_by_policy}",
        "requestId":"{req_id_from_DCAE}",
        "originatorId":"POLICY"
    },
    "actionIdentifiers":{
        "mode":"sync",
        "blueprintName":"{blueprint_name_from_operational_policy_config}",
        "blueprintVersion":"{blueprint_version_from_operational_policy_config}",
        "actionName":"{blueprint_action_name_from_operational_policy_config}"
    },
    "payload":{
        "$actionName-request":{
            "resolution-key":"{generated_by_policy}",
            "$actionName-properties":{
                "$aai_node_type.$aai_attribute_1":"",
                "$aai_node_type.$aai_attribute_2":"",
                .........
                "data":"{static_payload_data_from_operational_policy_config}",
                "$additionalEventParam_1":"",
                "$additionalEventParam_2":"",
                .........
            }
        }
    }
}'

3.1.5 Examples

Sample CBA execute request generated by Policy for PNF target type when "data" field is a string:

curl -X POST \
  'http://{{ip}}:{{port}}/api/v1/execution-service/process' \
  -H 'Authorization: Basic Y2NzZGthcHBzOmNjc2RrYXBwcw==' \
  -H 'Content-Type: application/json' \
  -H 'cache-control: no-cache' \
  -d '{
    "commonHeader":{
        "subRequestId":"14384b21-8224-4055-bb9b-0469397db801",
        "requestId":"d57709fb-bbec-491d-a2a6-8a25c8097ee8",
        "originatorId":"POLICY"
    },
    "actionIdentifiers":{
        "mode":"sync",
        "blueprintName":"PNF-demo",
        "blueprintVersion":"1.0.0",
        "actionName":"reconfigure-pnf"
    },
    "payload":{
        "reconfigure-pnf-request":{
            "resolution-key":"8338b828-51ad-4e7c-ac8b-08d6978892e2",
            "reconfigure-pnf-properties":{
                "pnf.equip-vendor":"Vendor-A",
                "pnf.ipaddress-v4-oam":"10.10.10.10",
                "pnf.in-maint":false,
                "pnf.pnf-ipv4-address":"3.3.3.3",
                "pnf.resource-version":"1570746989505",
                "pnf.nf-role":"ToR DC101",
                "pnf.equip-type":"Router",
                "pnf.equip-model":"model-123456",
                "pnf.frame-id":"3",
                "pnf.pnf-name":"demo-pnf",
                "data": "peer-as=64577",
                "peer-group":"demo-peer-group",
                "neighbor-address":"4.4.4.4"
            }
        }
    }
}'

Sample CBA execute request generated by Policy for VNF target type when "data" field is a valid JSON string:

curl -X POST \
  'http://{{ip}}:{{port}}/api/v1/execution-service/process' \
  -H 'Authorization: Basic Y2NzZGthcHBzOmNjc2RrYXBwcw==' \
  -H 'Content-Type: application/json' \
  -H 'cache-control: no-cache' \
  -d '{
    "commonHeader":{
        "subRequestId":"14384b21-8224-4055-bb9b-0469397db801",
        "requestId":"d57709fb-bbec-491d-a2a6-8a25c8097ee8",
        "originatorId":"POLICY"
    },
    "actionIdentifiers":{
        "mode":"sync",
        "blueprintName":"vFW-CDS",
        "blueprintVersion":"1.0.0",
        "actionName":"config-deploy"
    },
    "payload":{
        "config-deploy-request":{
            "resolution-key":"6128eb53-0eac-4c79-855c-ff56a7b81141",
            "config-deploy-properties":{
                "service-instance.service-instance-id":"40004db6-c51f-45b0-abab-ea4156bae422",
                "generic-vnf.vnf-id":"8d09e3bd-ae1d-4765-b26e-4a45f568a092",
                "data":{
                    "active-streams":"7"
                }
            }
        }
    }
}'

4. Operational Policy configuration to use CDS as an actor

TODO: Update the documentation once Operational Policy is made TOSCA compliant as per: https://wiki.onap.org/display/DW/TOSCA+Compliant+Policy+Types

Until then below is how to configure the Operational Policy to use CDS as an actor using the Policy API.

For integration testing use CLAMP UI to configure the Operational Policy

4.2 Control Loop Operational Policy YAML to use the CDS actor

Below is a template for configuring the Operational Policy to use CDS as an actor.

controlLoop:
  version: 2.0.0
  controlLoopName: {{Unique ID for the Control Loop, must match one of the IDs defined in the list of policies below}}
  trigger_policy: {{ID of operation policy defined below to specify which policy to trigger first}}
  timeout: {{Overall timeout for the Control loop Operational policy}}
  abatement: false
policies:
  - id: {{ID of the Operation policy}}
    name: {{Name of the Operation policy}}
    description: {{Description of the Operation policy}}
    actor: {{Identifies the actor of choice for remediation, in this case: CDS}}
    recipe: {{Identifies the CDS action-name}}
    target:
      resourceID: {{SDC resource ID: E.g. modelInvariant ID of the vFW generic VNF; empty for PNF}}
      type: {{Identifies the type of target, possible values: VNF, PNF}}
    payload:
      artifact_name: {{Name of the blueprint to execute if CDS is the actor}}
      artifact_version: {{Version of the blueprint to execute if CDS is the actor}}
      mode: async
      data: {{Additional static data required by the blueprint if CDS is the actor}}
    retry: 0
    timeout: {{Timeout in seconds for the actor to perform the operation}}
    success: final_success
    failure: final_failure
    failure_timeout: final_failure_timeout
    failure_retries: final_failure_retries
    failure_exception: final_failure_exception
    failure_guard: final_failure_guard

E.g. Sample Operational Policy YAML for vFW usecase:

controlLoop:
  version: 2.0.0
  controlLoopName: ControlLoop-vFirewall-7e4fbe9c-d612-4ec5-bbf8-605aeabdb677
  trigger_policy: unique-policy-id-1-modifyConfig
  timeout: 60
  abatement: false
policies:
  - id: unique-policy-id-1-modifyConfig
    name: modifyconfig-cds-actor
    description:
    actor: CDS
    recipe: modify-config
    target:
      resourceID: 7e4fbe9c-d612-4ec5-bbf8-605aeabdb677
      type: VNF
    payload:
      artifact_name: vFW-CDS
      artifact_version: 1.0.0
      data: '{"active-streams":"7"}'
    retry: 0
    timeout: 30
    success: final_success
    failure: final_failure
    failure_timeout: final_failure_timeout
    failure_retries: final_failure_retries
    failure_exception: final_failure_exception
    failure_guard: final_failure_guard

4.3 API to configure the Control Loop Operational policy

Once the YAML is built, we need to encode it in order to embed it into the payload to configure the operational policy. Assuming the YAML is saved into a file by name "policy.yaml", use the below script to encode the spaces and tabs:

#!/usr/env/bin python3
import urllib
with open('policy.yaml') as f:
  v = f.read()
v = urllib.quote_plus(v)
print(v)

The encoded YAML data from the above step needs to be substituted into the following payload template to create the operational policy.

Note: In the below rest endpoint, the hostname points to K8S service "policy-api" and internal port 6969.

curl -X POST \
  https://{$POLICY_API_URL}:{$POLICY_API_SERVICE_PORT}/policy/api/v1/policytypes/onap.policies.controlloop.Operational/versions/1.0.0/policies \
  -H 'Authorization: Basic aGVhbHRoY2hlY2s6emIhWHp0RzM0' \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{
  "policy-id" : "operational.modifyconfig",
  "content" : "$encoded_yaml_data"
}'

The response to this rest endpoint returns something like below:

{
    "policy-id": "operational.modifyconfig",
    "policy-version": "1",
    "content": "$data"
}

To run the below request, for policy-version use the response above into the format "${policy-version_from_last_call}.0.0") Note: In the rest endpoint URI, the hostname points to the service "policy-pap" and internal port 6969.

curl -X POST \
  https://{$POLICY_PAP_URL}:{$POLICY_PAP_SERVICE_PORT}/policy/pap/v1/pdps/policies \
  -H 'Authorization: Basic aGVhbHRoY2hlY2s6emIhWHp0RzM0' \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  -d '{
  "policies": [
    {
      "policy-id": "operational.modifyconfig",
      "policy-version": "1.0.0"
    }
  ]
}'

To view the configured policies use the below REST API.

curl -X GET \
  https://{$POLICY_API_URL}:{$POLICY_API_SERVICE_PORT}/policy/api/v1/policytypes/onap.policies.controlloop.Operational/versions/1.0.0/policies/operational.modifyconfig \
  -H 'Authorization: Basic aGVhbHRoY2hlY2s6emIhWHp0RzM0' \
  -H 'Content-Type: application/json' \