Architecture

AAI Architecture in ONAP

AAI provides ONAP with its logically centralized view of inventory data, taking in updates from orchestrators, controllers, and assurance systems. With that responsibility, it takes on a key data management role, providing the ONAP components not only the current “as-built” view of the services, but also the view into the data of the system itself; it’s integrity, it’s chronology, and where the source of the information can be found.

In addition to inventory and topology management, AAI provides the ability to do inventory administration. Data in AAI is continually updated in real-time as changes are made within the cloud. Because AAI is metadata-driven, new resources and services can be added quickly with Service Design and Creation (SDC) catalog definitions, using the AAI model loader, thus eliminating the need for lengthy development cycles. In addition, new inventory item types can be added quickly through schema configuration files.

AAI’s Role in ONAP

AAI is where the data converges, where the pictures come together, and where the ONAP actor systems ask questions so they can make their decisions. As new network or data center resources become available, AAI is updated with their specifics via REST APIs. When new service types are designed, or new services instantiated, systems keep AAI up to date of their deployment at each step of the way. As telemetry is gathered for the services as well as their underlying infrastructure, the health and analytics conclusions reached are stored in AAI as state information. When assurance systems detect a failure, AAI is queried to determine the extent of the impact.

With the high volume and variety of data, AAI must be prepared to answer many types of queries; real-time search to quickly retrieve specific items from an ocean of data, relationships to determine impacts and consequences, aggregations and counts to explore availability and consumption, validation and integrity to establish whether systems are acting on good information, history and provenance to reconstruct the current view and its context, and enrichment out to legacy systems to examine the low-level details of the network and virtual assets.

AAI Components

ESR

Applications for management of external systems.

aai/esr-gui	External system management ui. UI for esr-server.
aai/esr-server	ESR backend, mainly include the function of external system reachable check and data pretreatment.

Input abstraction

Applications that serve as entry points to A&AI.

aai/model-loader	Obtains SDC artifacts and loads them into the A&AI Resources service for storage.
aai/sparky-be	AAI user interface back end.
aai/sparky-fe	AAI user interface front end.

Query abstraction

Query abstraction point for clients that routes AAI queries and event data.

aai/data-router

AAI Microservice used to route AAI queries and event data to correct storage engine. Serves as a query abstraction point for clients, as well as a gateway.

Data management

Microservices that facilitate data management of AAI objects.

aai/babel	AAI Microservice to generate AAI model XML from SDC TOSCA CSAR artifacts.
aai/cacher	Cacher is a generic service that can be used to snapshot json responses, force sync them, sync them periodically, or update them by consuming dmaap events.
aai/chameleon	(deprecated) Abstraction service for historical database.
aai/champ	Abstraction from underlying graph storage systems that A&AI would interface with.
aai/gizmo	(deprecated) CRUD Rest API endpoint for resources and relationships, delivering atomic interactions with the graph for improved scalability.
aai/resources	AAI Resources Micro Service providing CRUD REST APIs for inventory resources. This microservice provides the main path for updating and searching the graph - java-types defined in the OXM file for each version of the API define the REST endpoints - for example, the java-type “CloudRegion” in aai-common/aai-schema/src/main/resources/oxm/aai_oxm_v11.xml maps to /aai/v11/cloud-infrastructure/cloud-regions/cloud-region.
aai/search-data-service	Abstraction layer for searchengine, supporting queries and updates. Currently supports Elasticsearch, but has also been design with Solr support in mind.
aai/spike	(deprecated) Microservice used to generate events describing changes to the graph data.
aai/tabular-data-service	(deprecated) Microservice which serves as an abstraction layer to a tabular data store.
aai/validation	Microservice used to invoke validation mechanism .

Graph services

Set of components, which store, provide or display schemas.

aai/graphadmin	Microservice with various functions for graph management.
aai/graphgraph	Microservice used to provide view of AAI model, schema and edge rules.
aai/schema-service	Application holds and provides specified schema versions.
aai/traversal	AAI Traversal Micro Service providing REST APIs for traversal/search of inventory resources. Custom queries (gremin-style traversals) model based queries (which use a model either manually created or loaded from SDC models) and named-queries (traversals which ignore edge labels and direction and just link together objects of given node types from a starting node).

Libraries

Libraries don’t run as standalone applications. They contain general functionality, which may be imported and used in other modules.

aai/aai-common	This holds the model, annotations and common modules used across the Resources and Traversal micro services. aai/aai-common creates artifacts like aai-core, aai-schema and aai-annotations, which are used by the rest of the microservices and libraries.
aai/event-client	Event bus client library.
aai/logging-service	AAI common logging library.
aai/rest-client	Library for making REST calls.
aai/router-core	Library containing the core camel components for the data router.

Configuration repositories

Contain several repositories that include various configuration.

aai/aai-data	(deprecated) AAI Chef environment files.
aai/aai-config	(deprecated) AAI Chef cookbooks.
aai/aai-service	(deprecated) AAI REST based services.
aai/oom
aai/test-config	Repository containing test configuration for use in continuous integration.