Agent Based Application Tools for Cloud Provisioning and Management - Cloud Computing - page 37

5 Application Tools
A set of tools have been designed and developed to support the orchestration of
Cloud Agency services by different type of Cloud users. The orchestrator can be
actually personified by both a human user and by an autonomic application. In
the first case the user takes the hat of a Cloud administrator, in the second case
it is a developer that design the application. The list of tools includes some APIs
for development of legacy applications and mOSAIC Cloud applications. For sake
of space we skip the description of mOSAIC APIs development here. Instead we
present two implementations of a Cloud Agency console and a Monitoring tool.
5.1 Cloud Agency Client API
A s e t o f JAVA API s support the development of event based client applica-
tion of Cloud Agency. According to the event-driven interaction model the API
allows for sending asynchronous and synchronous requests and for handling asyn-
chronous notifications by implementing callbacks. The class diagram of a typical
client application is shown in Fig. 2.
Fig. 2. Class diagram of Cloud Agency Client API
The blue colored classes represent the core API. The main goals of each class
are described in Table 1.
In addition to the core API, several implementations of core abstract classes
are provided. In particular:
- stubs : a stub offers a set of methods to invoke the Cloud Agency services.
These methods wrap the REST requests in order to query the Cloud Agency
RESTFull interface and to perform actions on Cloud resources or to obtain
information about the state of the Cloud infrastructure. At the state-of-the-
art of the development API client there are four classes that implement the
CAStub class and that provide methods to invoke provisioning, management,
monitoring and reconfiguration services;