NAP Application Controller (APPC) Client Library Guide

+-----------------+------------------+
+-----------------+------------------+
| Revision        | Version 1.0.0    |
+-----------------+------------------+
| Revision Date   | 22 August 2017   |
+-----------------+------------------+

+--------------+------------+---------------+--------------------------------------------------+
| Date         | Revision   | Author        | Changes                                          |
+--------------+------------+---------------+--------------------------------------------------+
| 2017-08-22   | 1.0.0      | Paul Miller   | First draft consistent with AT&T Release 17.10   |
+--------------+------------+---------------+--------------------------------------------------+
+--------------+------------+---------------+--------------------------------------------------+

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**
**

1. .. rubric:: Introduction
      :name: introduction

   1. .. rubric:: Target Audience
         :name: target-audience

    This document is for an advanced technical audience, which includes
    engineers and technicians. Document revisions occur with the release
    of new software versions.

Related Documentation
---------------------

    For additional information, see the ONAP Application Controller
    (APPC) API Guide.

    The following sections describe the conventions this document uses,
    including notices, text conventions, and command-line conventions.

Command-line Conventions
========================

The following table lists possible elements in a command-line path.

+------------------+--------------------------------------------------------------------------------------------------------+
| **Convention**   | **Description**                                                                                        |
+==================+========================================================================================================+
| Brackets [ ]     | This is used for optional items.                                                                       |
+------------------+--------------------------------------------------------------------------------------------------------+
| Braces { }       | This indicates choices separated by pipe (\|) for sets from which only one is selected. For example:   |
|                  |                                                                                                        |
|                  | {even\|odd}                                                                                            |
+------------------+--------------------------------------------------------------------------------------------------------+
| Blue text        | This indicates a link in this document online.                                                         |
+------------------+--------------------------------------------------------------------------------------------------------+

Text Conventions
~~~~~~~~~~~~~~~~

    The following table lists text conventions in this document.

+------------------------------------+----------------------------------------------------------------------------+
| **Convention**                     | **Description**                                                            |
+====================================+============================================================================+
| Monospace font with blue shading   | This font indicates sample codes, screenshots, or elements. For example:   |
|                                    |                                                                            |
|                                    | contact": {                                                                |
|                                    |                                                                            |
|                                    | 		   "contactType": "USER",                                         |
|                                    | 		   "source": "appl",                                              |
|                                    |                                                                            |
|                                    | 		   }                                                              |
+------------------------------------+----------------------------------------------------------------------------+
| *Italics*                          | Emphasizes a point or denotes new terms defined in the text.               |
|                                    |                                                                            |
|                                    | Indicates an external book title reference.                                |
+------------------------------------+----------------------------------------------------------------------------+
| Numeric                            | A number composed of digits 0 through 9.                                   |
+------------------------------------+----------------------------------------------------------------------------+
| Text                               | Any combination of alphanumeric characters.                                |
|                                    |                                                                            |
|                                    | New items in RED                                                           |
+------------------------------------+----------------------------------------------------------------------------+

Authors and Contributors
------------------------

    The following table lists the persons who are authors and
    contributors to this document.

+--------------------+----------------------+
| **Contributors**   |
+====================+======================+
| Borislav Glozman   | Margrethe Fossberg   |
+--------------------+----------------------+
| Paul Mellor        | John Buja            |
+--------------------+----------------------+
+--------------------+----------------------+

Terms and Acronyms
------------------

The following table defines terms and acronyms used in this document.

+-----------------------+--------------------------------------------------------------+
| **Term or Acronym**   | **Definition**                                               |
+=======================+==============================================================+
| AAI                   | Active and Available Inventory                               |
+-----------------------+--------------------------------------------------------------+
| AAF                   | Authentication & Authorization Framework                     |
+-----------------------+--------------------------------------------------------------+
| AJSC                  | AT&T Java Service Container                                  |
+-----------------------+--------------------------------------------------------------+
| API                   | Application Programming Interface                            |
+-----------------------+--------------------------------------------------------------+
| APPC                  | Application Controller                                       |
+-----------------------+--------------------------------------------------------------+
| SDC                   | Service Design and Creation                                  |
+-----------------------+--------------------------------------------------------------+
| DCAE                  | Data Collection Analytics and Events                         |
+-----------------------+--------------------------------------------------------------+
| DG                    | Directed Graph                                               |
+-----------------------+--------------------------------------------------------------+
| DNS                   | Domain Name System                                           |
+-----------------------+--------------------------------------------------------------+
| EELF                  | Event and Error Logging Framework                            |
+-----------------------+--------------------------------------------------------------+
| HDFS                  | Hadoop Distributed File System                               |
+-----------------------+--------------------------------------------------------------+
| HTTP                  | Hypertext Transfer Protocol                                  |
+-----------------------+--------------------------------------------------------------+
| IAAS                  | Infrastructure As A Service                                  |
+-----------------------+--------------------------------------------------------------+
| I/O                   | Input/Output                                                 |
+-----------------------+--------------------------------------------------------------+
| JMS                   | Java Messaging Service                                       |
+-----------------------+--------------------------------------------------------------+
| JSON                  | JavaScript Object Notation                                   |
+-----------------------+--------------------------------------------------------------+
| LAN                   | Local Area Network                                           |
+-----------------------+--------------------------------------------------------------+
| LRM                   | Local Resource Monitor                                       |
+-----------------------+--------------------------------------------------------------+
| SO                    | Service Orchestrator                                         |
+-----------------------+--------------------------------------------------------------+
| NOD                   | Network on Demand                                            |
+-----------------------+--------------------------------------------------------------+
| ODL                   | OpenDaylight                                                 |
+-----------------------+--------------------------------------------------------------+
| ONAP                  | Open Network Application Platform                            |
+-----------------------+--------------------------------------------------------------+
| OS                    | Operating System                                             |
+-----------------------+--------------------------------------------------------------+
| PO                    | Platform Orchestrator                                        |
+-----------------------+--------------------------------------------------------------+
| RCT                   | Reference Connection Tool                                    |
+-----------------------+--------------------------------------------------------------+
| RO                    | Resource Orchestrator                                        |
+-----------------------+--------------------------------------------------------------+
| SDN-C                 | Software Defined Network - Controller                        |
+-----------------------+--------------------------------------------------------------+
| SDN-GP                | Software Defined Network -  Global Platform                  |
+-----------------------+--------------------------------------------------------------+
| SME                   | Subject Matter Expert                                        |
+-----------------------+--------------------------------------------------------------+
| SNMP                  | Simple Network Management Protocol                           |
+-----------------------+--------------------------------------------------------------+
| SMTP                  | Simple Mail Transfer Protocol                                |
+-----------------------+--------------------------------------------------------------+
| SOT                   | Source Of Truth (ext. system where data object originates)   |
+-----------------------+--------------------------------------------------------------+
| SSH                   | Secure Shell                                                 |
+-----------------------+--------------------------------------------------------------+
| TCP                   | Transmission Control Protocol                                |
+-----------------------+--------------------------------------------------------------+
| TPS                   | Transactions per Second                                      |
+-----------------------+--------------------------------------------------------------+
| UEB                   | Universal Event Broker                                       |
+-----------------------+--------------------------------------------------------------+
| vCE                   | virtual CE (Customer Edge) router                            |
+-----------------------+--------------------------------------------------------------+
| vPE                   | virtual PE (Provider Edge) router                            |
+-----------------------+--------------------------------------------------------------+
| VLAN                  | Virtual Local Area Network                                   |
+-----------------------+--------------------------------------------------------------+
| VM                    | Virtual Machine                                              |
+-----------------------+--------------------------------------------------------------+
| VNF                   | Virtual Network Function                                     |
+-----------------------+--------------------------------------------------------------+
| VNFC                  | Virtual Network Function Component                           |
+-----------------------+--------------------------------------------------------------+
| vSCP                  | Virtualized Service Control Point                            |
+-----------------------+--------------------------------------------------------------+
| WAN                   | Wide Area Network                                            |
+-----------------------+--------------------------------------------------------------+
| WUI                   | Web User Interface                                           |
+-----------------------+--------------------------------------------------------------+
| XML                   | Extensible Markup Language                                   |
+-----------------------+--------------------------------------------------------------+
| YAML                  | YAML Ain't Markup Language                                   |
+-----------------------+--------------------------------------------------------------+

Client Library Background
-------------------------

    This guide discusses the Application Controller (APPC) Client
    Library and how to use it.

About the Client Library
------------------------

    The APPC client library provides consumers of APPC capabilities with
    a strongly-typed Java interface and encapsulates the actual
    interaction with the APPC component over an asynchronous messaging
    channel such as UEB.

Consumer Logic
--------------

    The client application that consumes APPC's capability for VNF
    lifecycle management (the APPC client library) can be implemented
    against the lightweight and strongly-typed Java API exposed by the
    APPC client library. The library does not try to impose
    architectural constraints upon clients, but instead provides support
    for different options and styles of API. It is the responsibility of
    the client application to select the most suitable paradigm to use;
    for example, a client may choose to use blocking calls as opposed to
    asynchronous notifications.

VNF Lifecycle Management API
----------------------------

    The API represents a relatively thin layer that consists mainly of
    business interfaces with strongly-typed APIs and a data object model
    created for the convenience of the consumer application.Â 

    The original YANG schema used by the APPC component and the
    underlying MD-SAL layer on the server-side generates these
    artifacts.

APP-C Client Library Flow
-------------------------

    |image0|

Asynchronous Flow
~~~~~~~~~~~~~~~~~

-  The APPC Client Library is called using an asynchronous API using a
   full command object, which is mapped to a JSON representation.

-  The APPC client calls the UEB client and sends the JSON command to a
   configured topic.

-  The APPC client pulls response messages from the configured topic.

-  On receiving the response for the command, the APPC client runs the
   relevant callback method of the consumer ResponseHandler.

   1. .. rubric:: Synchronous Flow
         :name: synchronous-flow

-  The APPC Client Library is called using a synchronous API using a
   full command object, which is mapped to a JSON representation.

-  The APPC client calls the UEB client and sends the JSON command to a
   configured topic.

-  The APPC client pulls response messages from the configured topic.

-  On receiving the **final** response for the command, the APPC client
   returns the response object with a final status.

1. .. rubric:: Client Library Usage
      :name: client-library-usage

   1. .. rubric::  Jar Files
         :name: jar-files

    The Java application that runs the APPC client kit uses the
    following jar files:

-  com.att.appc.client.client-kit

-  com.att.appc.client.client-lib

    The client library JAR files are located in the repository under
    /gerrit.onap.org/r/p/appc.git/appc-client.

Initialization
~~~~~~~~~~~~~~~~

    Initialize the client by calling the following method:

    AppcClientServiceFactoryProvider.getFactory(AppcLifeCycleManagerServiceFactory.class).createLifeCycleManagerStateful()

    Specify the following configuration properties as method parameters:

-  "topic.read"

-  "topic.read.timeout"

-  "topic.write"

-  "client.key"

-  "client.secret"

-  "client.name"

-  "client.name.id"

-  "poolMembers"

-  "client.response.timeout"

-  "client.graceful.shutdown.timeout"

Shutdown
~~~~~~~~

Shutdown the client by calling the following method:

void shutdownLifeCycleManager(boolean isForceShutdown)

If the isForceShutdown flag is set to false, the client shuts down as
soon as all responses for pending requests are received, or upon
configurable timeout. (client.graceful.shutdown.timeout).

If the isForceShutdown flag is set to true, the client shuts down
immediately.

Invoking LCM Commands
~~~~~~~~~~~~~~~~~~~~~

Invoke the LCM commands by:

-  Creating input objects, such as AuditInput, LiveUpgradeInput, with
   relevant command information.

-  Executing commands asynchronously, for example:

void liveUpgrade(LiveUpgradeInput liveUpgradeInput,
ResponseHandler<LiveUpgradeOutput> listener) throws
AppcClientException;)

In this case, client should implement the ResponseHandler<T> interface.

-  Executing commands synchronously, for example:

LiveUpgradeOutput liveUpgrade(LiveUpgradeInput liveUpgradeInput) throws
AppcClientException;)

Client API
----------

    After initializing the client, a returned Object of type
    LifeCycleManagerStateful defines all the Life Cycle Management APIs
    supported by APPC.

    The interface contains two definitions for each RPC: one for
    Asynchronous call mode, and one for Synchronous.

    In Asynchronous mode, client consumer should provide a callback
    function of type:

    ResponseHandler<RPC-NAMEOutput>

    where RPC-NAME is the command name, such as Audit or Snapshot.

    There may be multiple calls to the ResponseHandler for each response
    returned by APPC. For example, first 100 'accept' is returned, then
    400 'success'.

LifeCycleManagerStateful Interface
----------------------------------

    Generated from the APPC Yang model, this interface defines the
    services and request/response requirements for the ECOMP APPC
    component. For example, for LCM Command Audit, the following is
    defined:

    @RPC(name="audit", outputType=AuditOutput.class)

    AuditOutput audit(AuditInput auditInput) throws AppcClientException;

    For a Synchronous call to Audit, the consumer thread is blocked
    until a response is received or a timeout exception is thrown.

    @RPC(name="audit", outputType=AuditOutput.class)

    void audit(AuditInput auditInput, ResponseHandler<AuditOutput>
    listener) throws AppcClientException;

    For an Asynchronous call to Audit, a callback should be provided so
    that when a response is received the listener is called.

API documentation
-----------------

    The API documentation is also available as a swagger page generated
    from files at /client-kit/target/resources.

appc-provider-lcm
-----------------

This defines the services and request/response requirements for the APPC
component.

Methods
--------

The methods should match the actions described in the LCM API Guide. For
each method:

**Consumes**

This API call consumes the following media types using the
**Content-Type** request header:

-  application/json

**Request body**

The request body is the action name followed by Input (e.g., AuditInput)

**Return type**

The return type is the action name followed by Output (e.g.,
OutputInput)

**Produces**

This API call produces the following media types according to the
**Accept** request header; the **Content-Type** response header conveys
the media type.

-  application/json

**Responses**

200 Successful operation

401 Unauthorized

500 Internal server error

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