IdAS Registries Proposal

Introduction

This document describes a new approach to handling IdAS context provider configuration issues. It builds on work discussed at the F2F in Provo Jan 2007. This document works top down from use cases.

It proposes a design that divides the registry work into two completely separate registries. One ("IdASRegistry") is a registry of context providers. The other ("IdASContextRegistry") manages the binding between a ContextId and a (ContextProvider, config-data) pair.

Definitions

• a ContextId (aka "cid") an URI identifier of a Context. It may be an XRI. The intent is that cids are globally unique. In practice they may not be.
• IdAS is an attribute service aggregator/abstraction. It manages a set of statically or dynamically installed Context Providers.
• A Context Provider (analogous to a JDBC driver) acts as a factory for IContexts

Use Cases

1. create a new (IContext, cid) combination
2. connect to existing cid (returns IContext)
3. open an IContext
4. close an IContext
5. destroy a cid

Non-Use Case

1. associate existing IContext with cid

Objects

• cid = ContextId (indentifier)
• config = Config data
• IContext = a Context instance
• cpid = id of a context provider (IContextFactory class name)
• cf = a context factory (i.e. IContextFactory)

Services

• IdAS
• IdASContextRegistry --registry of ContextIds
• IdASRegistry --registry of available cps
• cp --a context provider

IdAS

cid create(cpid, config)
IContext connect(cid)
destroy(cid)

cp (Context Provider)

cid create(config)
void destroy(config)
IContext connect(cid)

IContext

SubjectId open(callbackHandler)
void close()
void destroy()

IContextFactory

IContext createContext(config)

IdASContextRegistry

void register(cid, cp, config)
void unregister(cid)
cpid&config resolve(cid)

IdASRegistry

cf getContextFactory(cpid)
void registerContextFactory(cf)
void removeContextFactory(cf)

IdAS Implementation

cid create(cpid, config)
{
 cf = IdASRegistry.getContextFactory(cpid); 
 cid = cf.createContext(config);
 IdASContextRegistry.register(cid, cpid, config); 
 return cid;
}

IContext connect(cid) 
{
 cpid+config = IdASContextRegistry.resolve(cid);
 cp = IdASRegistry.get(cpid);
 IContext = cp.connect(config);
}

void destroy(cid)
{
 cpid+config = IdASContextRegistry.resolve(cid); 
 cp = IdASRegistry.get(cpid);
 cp.destroy(config)  
}

IdASContextRegistry Implementation

void register(cid, cpid, config)
{
 // if cid is an XRI, resolve it to an URL
 // HTTP get the XRDS document at URL
 // find the "Higgins IdAS Context Provider" service type within it
 // add cpid and config as "service metadata"
 // HTTP put updated XRDS document
}

cpid&config resolve(cid)
{
 // if cid is an XRI, resolve it to an URL
 // HTTP get the XRDS document
 // lookup the "Higgins IdAS Context Provider" service type with it
 // return cpid&config
}