| Technology Preview Warning - GEMINI has not yet been released | ||||||
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| WSRF (Web Services Resource Framework) and GEMINI Resources | ||||||
| GEMINI adopts the WSRF standard and the Globus 4 WS-Core Toolkit implementation of this standard in order to provide GEMINI application developers with a language-independent means of creating and using persistent, distributed services. The WSRF model defines persistent resources to be stateful objects that can be referred to via a small datum known as an EPR (EndPoint Reference). The EPR uniquely identifies a particular resource, including the location of the container hosting that resource. Each resource type is defined using standard WSDL (Web Services Definition Language) to specify the persistent attributes of a resource, as well as any associated service methods for that resource. | ||||||
| GEMINI's architecture currently defines the following high-level resource types (using WSDL) and provides container-side implementation of these resources and their assocated services. | ||||||
| Zone | ||||||
| The Zone resource is the factory and directory for all of the resources hosted by a particular container and 'owned' by a particular Zone. A Zone is typically associated with a user on a specific host. It is possible for given host to support multiple Zones, and for a Zone to be shared amongst multiple users. The important aspect of a Zone is that it is the manager of all of the other objects described below. | ||||||
| File | ||||||
| The GEMINI File resource is designed to allow arbitrary data to be stored persistently within GEMINI, and to allow this resource to be referred to by a WSRF EPR. These GEMINI Files then become the operands (inputs and outputs) to the other various services within GEMINI. In addition, the File is intended to maintain a rich set of metadata to allow easy cataloging and searching. | ||||||
| Task | ||||||
| A GEMINI Task resource is one component of the GEMINI workflow model. A Task contains all of the information about a function to be performed, including references to input and output Files, and any necessary operation parameters. A GEMINI Task is completely passive and its state is typically only manipulated by the initial creator of a Task, as well as by the various GEMINI agents that may operate on the task., | ||||||
| Agent | ||||||
| A GEMINI Agent is a resource that bridges between the world of GEMINI objects and the actual computational services necessary to get a job done. Agents are the enactors of all GEMINI activity and workflow. Agents act autonomously from the client program | ||||||