= !MapGuide RFC 105 - Enhance feature service !GetCapabilities API =

This page contains a change request (RFC) for the !MapGuide Open Source project.  
More !MapGuide RFCs can be found on the [wiki:MapGuideRfcs RFCs] page.


== Status == 
 
||RFC Template Version||(1.0)|| 
||Submission Date||July 20, 2010||
||Last Modified||Bruce Dechant July 20, 2010||
||Author||Bruce Dechant||
||RFC Status||draft||
||Implementation Status||incomplete||
||Proposed Milestone||2.3||
||Assigned PSC guide(s)||Bruce Dechant||
||'''Voting History'''||||
||+1||||
||+0||||
||-0||||
||-1||||
||Abstained||||
 
== Overview ==

This RFC proposes to add a NEW !GetCapabilites() API to the feature service which contains an additional connection string parameter. This will primarily allow for acquiring the "runtime" capabilities of WFS/WMS providers.

== Motivation ==

The existing Feature service !GetCapabilties() API works correctly for most providers, but fails to return the true capabilities of the server connected to by a WFS/WMS provider because there is no way to specify the connection string containing the server.

Here is a subset of the WFS capabilities showing the differences.

WFS provider returned capabilites (existing API):
{{{
<Filter>
  <SupportsGeodesicDistance>false</SupportsGeodesicDistance> 
  <SupportsNonLiteralGeometricOperations>true</SupportsNonLiteralGeometricOperations> 
</Filter>
}}}

WFS provider returned capabilites (NEW API with server specified in connection string):
{{{
<Filter>
  <Condition>
    <Type>Comparison</Type> 
    <Type>Like</Type> 
    <Type>Spatial</Type> 
  </Condition>
  <Spatial>
    <Operation>EnvelopeIntersects</Operation> 
    <Operation>Intersects</Operation> 
  </Spatial>
  <SupportsGeodesicDistance>false</SupportsGeodesicDistance> 
  <SupportsNonLiteralGeometricOperations>true</SupportsNonLiteralGeometricOperations> 
</Filter>
}}}

== Proposed Solution ==

 * Create a NEW !GetCapabilites() API that takes an additional connection string parameter. This NEW parameter will cause the API to behave exactly as before if it is an empty string.

Existing API:
{{{
    MgByteReader* GetCapabilities(CREFSTRING providerName);
}}} 

Proposed NEW API:
{{{
    MgByteReader* GetCapabilities(CREFSTRING providerName, CREFSTRING connectionString);
}}} 

== Implications ==

This change will NOT break existing API compatibility.

== Test Plan ==

!Build/Run on !Windows/Linux.

== !Funding/Resources ==

Supplied by Autodesk.