OpenSimulator Internals/Connector Architecture

OpenSimulator Internals/Connector Architecture

Overview

Connectors are the HTTP client layer that sits between region simulators and ROBUST grid services. Each connector implements a service interface (e.g. IAssetService, IPresenceService) using HTTP calls to the corresponding ROBUST handler.

The same interface may be implemented by:

• A local connector -- calls the service directly in-process (standalone mode or co-located services).
• A remote connector -- makes HTTP calls to a ROBUST server.
• An HG connector -- wraps the remote connector with hypergrid-specific logic.

Region code calls only the interface. Which implementation is loaded depends on configuration ([Architecture] section of the ini files).

See OpenSimulator Internals/ROBUST Services for the server-side service implementations.

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Connector Pattern

All remote connectors follow the same pattern:

1. Constructor receives IConfigSource and reads the service URL from config.
2. Each method serialises parameters to a REST or XMLRPC request.
3. Sends HTTP POST/GET/DELETE to the ROBUST handler endpoint.
4. Deserialises the response and returns the result.

The HTTP client layer is WebUtil (OpenSim/Framework/WebUtil.cs), which handles serialisation, connection pooling, and error logging.

See OpenSimulator Internals/Connector Architecture/Asset Connector for a fully worked example of the pattern including both client and server-side handler code.

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Individual Connector Pages

Connector	Service Interface	Notes
OpenSimulator Internals/Connector Architecture/Asset Connector	IAssetService	Includes server-side handler detail. HG variant wraps with foreign asset server logic.
OpenSimulator Internals/Connector Architecture/GridUser Connector	IGridUserService	Tracks last position, login/logout timestamps, home region.
OpenSimulator Internals/Connector Architecture/Presence Connector	IPresenceService	Online status, session tracking, region assignment.
OpenSimulator Internals/Connector Architecture/UserAccount Connector	IUserAccountService	User account CRUD. Known bug: CreateUser() sends first name as email value.
OpenSimulator Internals/Connector Architecture/Inventory Connector	IInventoryService	XInventory protocol. UpdateFolder() URL-encodes Name; AddFolder() does not.
OpenSimulator Internals/Connector Architecture/Authentication Connector	IAuthenticationService	Password and token authentication, impersonation mechanism.
OpenSimulator Internals/Connector Architecture/Avatar Connector	IAvatarService	Appearance storage. ResetAvatar() log erroneously says "SetItems reply".
OpenSimulator Internals/Connector Architecture/Friends Connector	IFriendsService	Friend list, online notifications.
OpenSimulator Internals/Connector Architecture/Grid Connector	IGridService	Region registration, lookup, neighbour queries.
OpenSimulator Internals/Connector Architecture/Simulation Connector	ISimulationService	Inter-simulator agent and object transfer. QueryAccess, CreateAgent, UpdateAgent, CloseAgent, CreateObject.
OpenSimulator Internals/Connector Architecture/UserAgent Connector	IUserAgentService	HG-only. Home region lookup, login to foreign grid, session verification.
OpenSimulator Internals/Connector Architecture/Gatekeeper Connector	IGatekeeperService	HG-only. Foreign grid entry point. GetHyperlinkRegion, LoginAgentToGrid.

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HG Connectors

HyperGrid introduces additional connectors that wrap or replace the standard ones:

• UserAgent Connector -- used by the source grid to contact the avatar's home grid UserAgent service during HG teleport.
• Gatekeeper Connector -- used to contact a foreign grid's Gatekeeper during HG destination resolution.
• HGAsset Connector -- used by HGInventoryAccessModule to fetch/push assets between grids (via HGAssetMapper).

These are documented in the individual connector pages above and in:

• OpenSimulator Internals/Code Map/HGEntityTransferModule
• OpenSimulator Internals/Code Map/InventoryAccessModule

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Configuration

Connectors are selected in the [Architecture] ini include files:

• config-include/StandaloneCommon.ini -- standalone mode, services loaded in-process.
• config-include/GridCommon.ini -- grid mode, remote connectors used.
• config-include/HGCommon.ini -- hypergrid additions.

The [ServiceList] section of Robust.ini selects which ROBUST handlers are loaded. The [Modules] section of OpenSim.ini selects which connectors the simulator loads.

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See Also

• OpenSimulator Internals/Code Map/ROBUST
• OpenSimulator Internals/ROBUST Services
• OpenSimulator Internals/Reading the Code
• OpenSimulator Internals/Code Map