Capabilities

=Introduction=

Capabilities are part of the communications protocol between a client and the region This correspond to a HTTP URL a client will use to perform a particular action, for example get a texture data. A region may provide the service for a capability, providing its URL for it, provide a URL of a external service or ignore it if not supported.

Opensimulator supports part of the capabilities that Third Part Viewers expect from Second Life, plus its own set

OpenSimulator capabilities
These are capabilities that a OpenSimulator region can setup for each client. Note that this list is version dependent, and may not be up to date

SEED the start capability
viewers connect to this with a list of the capabilities they need and service replies with the list of the URLs of those capabilities it supports some Information about viewer or region may also be included on request or reply some reply URLs may contain parts unique to the current client and region

Enabling and Disabling
Capabilities are enabled and disabled in OpenSimulator by setting a property with the name Cap_ in the [ClientStack.LindenCaps] configuration setting of OpenSim.ini. Default settings are present in file OpenSimDefaults.ini the value can be:
 * "" (or the capability property is not present on any ini file), the service is disabled.
 * "localhost", the service is provided by simulator
 * a valid URL, the service is provided by a external server

For instance, to disable the GetTexture capability, one would set

and to enable it

There are a large number of default capabilities set up in the OpenSimDefaults.ini file. As with other configuration settings, these will be overwritten by anything you set in the OpenSim.ini file.

=Mechanism= Here's a brief description of the mechanism by which a viewer entering a gird is provided with capability endpoints on first login. The mechanism is slightly different when user moves between regions after login. See SimulatorLoginProtocol for more details.


 * 1) The client requests login to the installation's login service.
 * 2) The login service decides destiny region, checking it it accepts the client
 * 3) The login service generates a seed key. This is a random key to generate a unique region URL for the client.
 * 4) The login service informs the destiny region about this client including the the seed key.
 * 5) The login service informs the client about the region access information, including a region URL for the seed (seed capability)
 * 6) The client establishes an initial child connection with the simulator with the UseCircuitCode UDP message.  The server triggers individual modules to register capabilities as required (e.g. the GetTextureModule registers a GetTexture capability, etc.).  As before, these capabilities have a random component.
 * 7) The client sends a HTTP request to the seed capability URL provided earlier, requesting a set of capabilities (GetTexture, etc.).  The simulator replies with the required capability URLs.
 * 8) The client can then make requests to specific capabilites.

You can see the capabilities set up with the "show caps list" simulator console command. Here's some example output from a test 0.9.2.0 Yeti.

Example of Capabilities sent to a particular viewer (0.9.2 Dev)
Region (root) # show caps list Region ubittest11: UpdateGestureTaskInventory            /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 UploadBakedTexture                    /CAPS/e7762177-b2d1-41c7-ba9d-4d5953883c1b0010/ GroupMemberData                       /CAPS/8ba20145-932e-4545-9f41-1588b1d7120b AgentPreferences                      /CAPS/449dcf05-aeba-4613-9fb7-cc154a17671a ObjectMedia                           /CAPS/250c3ad6-6515-485a-8391-6581599163ac HomeLocation                          /CAPS/eda48829-7713-4f29-a873-a49ff1e28cce UpdateScriptAgentInventory            /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 MapLayer                              /CAPS/ff37d443-2acc-4bdc-b35f-1c14480f0132 ServerReleaseNotes                    /CAPS/2c57351f-e9b2-4223-ba10-2324b8f807c0/ ProvisionVoiceAccountRequest          /CAPS/e7762177-b2d1-41c7-ba9d-4d5953883c1b0108/ ObjectMediaNavigate                   /CAPS/301278a3-49e6-46bf-a1c2-661fa97427f8 UpdateScriptTaskInventory             /CAPS/fcc995fb-1dfb-443e-aae9-933a17f03161 AvatarPickerSearch                    /CAPS/3d348ccb-7fda-4927-905b-e27e9d18db74/ ExtEnvironment                        /CAPS/f8d1a848-99f0-4cac-9293-f74a790a0dff/ UpdateScriptTask                      /CAPS/fcc995fb-1dfb-443e-aae9-933a17f03161 GetDisplayNames                       /CAPS/bd0f7c2d-6c5a-4e96-b998-9f8a6777c715 CopyInventoryFromNotecard             /CAPS/6fe40ffb-88f1-4483-963e-b5f94b9b60b3 FetchInventory2                       /CAPS/72be4350-439a-41c9-9782-2f2f402ec61b RenderMaterials                       /CAPS/e7762177-b2d1-41c7-ba9d-4d5953883c1b/ UpdateSettingsAgentInventory          /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 GetObjectCost                         /CAPS/3084898a-5ea9-48ab-a879-1e6c3609ade1 UpdateNotecardAgentInventory          /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 ParcelVoiceInfoRequest                /CAPS/e7762177-b2d1-41c7-ba9d-4d5953883c1b0107/ GetObjectPhysicsData                  /CAPS/6f9fd433-2b8b-458f-8340-49a34ec28d77 UpdateAgentInformation                /CAPS/449dcf05-aeba-4613-9fb7-cc154a17671a UpdateSettingsTaskInventory           /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 UpdateAnimSetAgentInventory           /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 UpdateAgentLanguage                   /CAPS/449dcf05-aeba-4613-9fb7-cc154a17671a SimulatorFeatures                     /CAPS/fe9a00a1-2025-4243-bc20-ba780b309216 EstateChangeInfo                      /CAPS/f8ef6e17-887c-47b2-afa4-bc6f348ac533/ UpdateGestureAgentInventory           /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 EstateAccess                          /CAPS/c6a89434-da8c-4ca5-91ce-0f6d50b01127/ LSLSyntax                             /CAPS/84363df8-df9d-4d20-aa6e-f898c37a4e6b ParcelPropertiesUpdate                /CAPS/8c22f06e-8174-482a-8923-e553a7a26ac2 CreateInventoryCategory               /CAPS/0464839f-a53b-40e4-ba67-e5e51ee586bd ObjectAdd                             /CAPS/280c3b36-e1cf-430d-ab2e-3b555d382c78/ ResourceCostSelected                  /CAPS/9847b0d8-21da-4c23-9743-970dee156bb8 UpdateScriptAgent                     /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 RemoteParcelRequest                   /CAPS/0939a467-aa93-42fb-b108-fd0ad4ea5c73 NewFileAgentInventory                 /CAPS/402dbdf7-e67a-4ab4-88b4-082700407971 SEED                                  /CAPS/e7762177-b2d1-41c7-ba9d-4d5953883c1b0000/ CustomMenuAction                      /CAPS/3f756ad1-539e-4873-a1af-d27642fe025b/ EnvironmentSettings                   /CAPS/e9f38618-e9aa-4bd5-86c3-dd0f8f8e5a45/ UpdateNotecardTaskInventory           /CAPS/8f912ed8-7072-40e6-ac27-7861f8eb5425 UploadObjectAsset                     /CAPS/02c0f42f-22e6-46a2-b892-4d8fd3e12097/ UntrustedSimulatorMessage             /CAPS/7abbc33f-9371-4e49-91bb-280843ab3210 SimConsoleAsync                       /CAPS/abb4ded1-9132-4e29-ab53-4fa13b1e3dfa/ MeshUploadFlag                        /CAPS/2ed68e7d-1637-4acb-8f0e-2c559fcd5238 EventQueueGet                         /CAPS/EQG/d23c8b9e-cf17-46af-a8cb-b887e4fa9f5b/ FetchInventoryDescendents2            /CAPS/3e19ee86-0ed1-4b20-a92a-94882652c03e/ GetTexture                            (deleted url)/CAPS/c27e9aa2-3b78-4d90-bc60-e977e9c3f3a3/ GetMesh                               (deleted url)/CAPS/61e945a7-c054-493e-8939-56f40ca09856/ GetMesh2                              (deleted url)/CAPS/59b7a937-af83-4d4e-9c38-42a28e1f2160/ ViewerAsset                           (deleted url)/CAPS/0c86e85c-4f1a-443d-8950-d1e0832db88f/
 * Circuit 1881454533:

NOTE: Caps format may change