MapGuide RFC 100 - Web Tier support for testing expressions and filters ¶

This page contains an change request (RFC) for the MapGuide Open Source project. More MapGuide RFCs can be found on the RFCs page.

Status ¶

RFC Template Version	(1.0)
Submission Date	(Date/Time submitted)
Last Modified	Jackie Ng, 25 June 2010
Author	Jackie Ng
RFC Status	draft
Implementation Status	pending
Proposed Milestone	2.3
Assigned PSC guide(s)	Jackie Ng
Voting History
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Overview ¶

This RFC proposes the Web tier APIs be extended to support the testing of FDO expressions.

Motivation ¶

The expression editor in MapGuide Maestro lacks the ability to test the entered FDO expression/filter for validity. While the simple solution would be to have Maestro use FDO directly (which provides services for testing/parsing expressions), this breaks portability (Maestro is a .net application. FDO's .net wrapper is not portable). Having this functionality available at the web tier level is a more convenient and portable solution.

Proposed Solution ¶

Add two new mapagent operations:

• Name: TESTEXPRESSION
• Parameters:
  • VERSION: 1.0.0
  • LOCALE: en
  • EXPRESSION: (the FDO expression to test)

• Name: TESTFILTER
• Parameters:
  • VERSION: 1.0.0
  • LOCALE: en
  • EXPRESSION: (the FDO filter to test)

Add the supporting native APIs to MgFeatureService (exported to SWIG with PUBLISHED_API)

class MgFeatureService
{
...
PUBLISHED_API:
    virtual bool TestExpression(CREFSTRING fdoExpr);
    virtual bool TestFilter(CREFSTRING fdoFilter);
...
};

Maestro's wrapper API will be updated to support these new mapagent commands.

Implications ¶

This is an API addition. Existing APIs are unaffected. As this is an addition to a PlatformBase API, other implementations of MgFeatureService (eg. AutoCAD Map3D Geospatial API) will have to implement these APIs as well.

Test Plan ¶

Test the http and web tier APIs with a series of valid and invalid FDO expressions. Verify the return result is true for all valid FDO expressions. Verify the return result is false for all invalid FDO expressions.

Funding/Resources ¶

Community based