MapServer Simple Viewer

.. _rfc63: =============================================================== MS RFC 63: Built-in OpenLayers map viewer =============================================================== :Date: 2010-09-25 :Author: Daniel Morissette (dmorissette at mapgears.com) :Author: Alan Boudreault (aboudreault at mapgears.com) :Last Edited: 2010-10-26 :Status: Adopted on 2010-10-29. Implementation complete. :Version: MapServer 6.0 :Id: $Id$ Overview ------------------------------------------------------------------------------ Users often request for a simple way to test mapfiles. This RFC proposes a **simple** way to preview, test and navigate a mapfile with MapServer using a built-in OpenLayers based map viewer that will be triggered via the cgi. This is for testing/development purposes only and not for production or deploying full-featured sites. This will use the a built-in **openlayers** template. It will return a simple html viewer based on OpenLayers. Note that GeoServer already provides a similar functionnality and this is what this RFC was inspired from. Implementation Details ------------------------------------------------------------------------------ In order to implement this enhancement, the following changes should be made in the MapServer codebase: * Add a built-in **openlayers** template. * Some new template tags will be needed. These tags will be used to construct the mapserver cgi url. - [mapserv_onlineresource] **or** - [protocol] - [host] - [program] See `ticket 3552 `_ for more detail. The template will be triggered using one of the following ways: * Using **mode=browse&template=openlayers**: The viewer will be initialized based on the mapfile defaults, and some of the traditional mapserv CGI params may also work (such as map size, layer selection, etc.) * Using **FORMAT=application/openlayers** in a WMS GetMap request: The rest of the GetMap parameters would be used to configure the map to view (BBOX, WIDTH, HEIGHT, LAYERS, etc.) Both cases would call the same functions internally to produce a simple OpenLayers viewer with one singletile layer for the whole map with the selected layers. Here's the simple viewer html code that could be used: :: MapServer Simple Viewer

OpenLayers Dependency ------------------------------------------------------------------------------ Obviously, this functionnality needs the OpenLayers javascript library. A minimal build will be used and hosted on the MapServer website at http://www.mapserver.org/lib/OpenLayers-ms60.js. The "ms60" suffix in the OpenLayers-ms60.js filename is so that we can increase the version number in the future if/when needed to match the requirements of future releases of MapServer. Users will also be able to use their own OpenLayers library in one of two ways: * Using a environment variable: by setting the environment variable MS_OPENLAYERS_JS_URL, MapServer will use that url rather than the default one. * Using a CONFIG setting in the mapfile: by adding the config variable MS_OPENLAYERS_JS_URL in a mapfile, MapServer will use that url rather than the default one. Files affected ------------------------------------------------------------------------------ To determine... Further Considerations ------------------------------------------------------------------------------ In the future, we may provide a mechanism to support multiple frameworks and ship generic templates with MapServer. Bug ID ------------------------------------------------------------------------------ The ticket for RFC-63 (containing the implementation) can be found here. Ticket 3549_ .. _3549: http://trac.osgeo.org/mapserver/ticket/3549 Ticket 3552_ .. _3552: http://trac.osgeo.org/mapserver/ticket/3552 Voting history ------------------------------------------------------------------------------ Adopted on 2010-10-29 with +1 from SteveL, DanielM, JeffK, AssefaY, TomK, TamasS, SteveW and PerryN.