From: Alan Webb <awebb@linux.vnet.ibm.com>

The change makes two principal implementation changes:

[1] It removes the hard coded set of possible asset server client
implementations, allowing any arbitrary implementation that has been
identified to the PluginLoader as an appropriate extension. The
extension point for asset server client extension
is /OpenSim/AssetServerClient. All of the old configuration rules have
been preserved, and any of the legacy configuration values will still
work as they did before, except the implementation is now loaded as a
plug-in, rather than as a hard-coded instantiation of a specific class.
The re-hashing of IAssetServer as an extension of IPlugin made upgrading
of the implementation classes a necessity.

Caveat: I have not been able to meaningfully test the crypto-grid
clients. I believe they should work correctly, but the refactoring
necessary to handle plug-in based initialization (vs constructor-based
initialisation) admits the possibility of a problem.

[2] The asset cache implementation, previously introduce as a hard-code
class instantiation is now implemented as an IPlugin. Once again the
previous (configurationless) behavior has been preserved. But now it is
possible for those interested in experimenting with cache technologies
to do so simply by introducing a new extension for the asset cache
extension point (/OpenSim/AssetCache).

I've tested all of the configuration settings, after applying the patch
to a newly extracted tree, and they seem to work OK.

2 files changed, 20 insertions, 1 deletions

diff --git a/bin/OpenSim.addin.xml b/bin/OpenSim.addin.xml
index 122a1a8..707eaf3 100644
--- a/bin/OpenSim.addin.xml
+++ b/bin/OpenSim.addin.xml
@@ -3,7 +3,13 @@
         <Import assembly="OpenSim.exe"/>
         <Import assembly="OpenSim.Framework.dll"/>
     </Runtime>
-    <ExtensionPoint path = "/OpenSim/Startup">
+    <ExtensionPoint path="/OpenSim/Startup">
         <ExtensionNode name="Plugin" type="OpenSim.Framework.PluginExtensionNode" objectType="OpenSim.IApplicationPlugin"/>
     </ExtensionPoint>
+    <ExtensionPoint path="/OpenSim/AssetCache" name="Region Asset Cache Plugin-point" >
+        <ExtensionNode name="Cache" type="OpenSim.Framework.PluginExtensionNode" objectType="OpenSim.Framework.IAssetCache"/>
+    </ExtensionPoint>
+    <ExtensionPoint path="/OpenSim/AssetServerClient" name="Region Asset Cache Server Interface Plugin-point">
+        <ExtensionNode name="ServerClient" type="OpenSim.Framework.PluginExtensionNode" objectType="OpenSim.Framework.IAssetServer"/>
+    </ExtensionPoint>
 </Addin>
diff --git a/bin/OpenSim.ini.example b/bin/OpenSim.ini.example
index 0e1958e..3469c2a 100644
--- a/bin/OpenSim.ini.example
+++ b/bin/OpenSim.ini.example
@@ -110,6 +110,8 @@
     ;
     ; If set to local then the local database based asset service will be used in standalone and grid modes
     ; If set to grid then the grid based asset service will be used in standalone and grid modes
+    ; All other values will cause a search for a matching assembly that contains an asset server client.
+    ; See also: AssetCache
     asset_database = "default"   
 
     ; Persistence of changed objects happens during regular sweeps. The following control that behaviour to
@@ -197,6 +199,17 @@
     ;WorldMapModule = "WorldMap"
     ;MapImageModule = "MapImageModule"
         
+    ; ##
+    ; ## Customized Cache Implementation
+    ; ##
+    ;
+    ; The AssetCache value allows the name of an alternative caching
+    ; implementation to be specified. This can normally be omitted.
+    ; This value corresponds to the provider value associated with the
+    ; intended cache implementation plugin.
+    ; See also: asset_database
+
+    ; AssetCache = "OpenSim.Framework.Communications.Cache.AssetCache"
 
     ; ##
     ; ## EMAIL MODULE