root/tags/rel-5-0-2/mapserver/rfc/ms-rfc-9.txt
| Revision 6822, 2.0 kB (checked in by hobu, 1 year ago) | |
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MS RFC 9: Item tag for query templates
| Date: | 2006/01/05 |
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| Author: | Steve Lime |
| Contact: | steve.lime@DNR.STATE.MN.US |
| Status: | Adopted |
| Version: | MapServer 4.10 |
Description: A the moment processing of attributes exposed via query templates is limited to a couple forms of escaping. This is too limiting. It would be much nicer to be able to apply a format to an attribute (e.g. truncate decimals or add a prefix) or detect when it is NULL or empty and present an alternative representation. This RFC describes a simple scheme to allow for extended processing of attributes before sending to the a users.
This would involve adding a new "item" tag to the template processor.
Files affected
- maptemplate.c => add tag processor, update query template processor to use tag processor.
Backwards compatabilty issues
N/A, new functionality. Existing methods for exposing an attribute (e.g. [attribute name] would continue to function, although we might mark that as depricated at some point.
Implementation Details
The "item" tag would have the following properties.
- name: the name of the attribute to be exposed
- format: a simple string containing the token(s) $value
- nullformat: string to return if value is NULL or empty (length=0)
- uc: convert string to upper case
- lc: convert string to lower case
- substr: perform a perl-like substring operation by providing offset, and optionally length
- commify: add commas to a numeric string (12345 would become 12,345)
- escape: what type of escaping to do (default is html), permissible values would be html, url, raw
We could add simple case statement support at a later date but the above would more than meet my needs at the momment.
Bug ID
1636
Voting history
+1: Lime, Morissette, Butler +0: Gillies, Warmerdam
