Bug report #3853

Problems with some WMS services (from toronto.ca/open)

Added by mgleahy - over 9 years ago. Updated over 9 years ago.

Status:Closed
Priority:Low
Assignee:nobody -
Category:Build/Install
Affected QGIS version: Regression?:No
Operating System:All Easy fix?:No
Pull Request or Patch supplied: Resolution:fixed
Crashes QGIS or corrupts data: Copied to github as #:13911

Description

I've notice a problem when I try to load layers from the WMS services listed at http://toronto.ca/open (follow the big "Get the Data" link, then scroll to the bottom of the page). When I connect to these directly within QGIS, I can see the list of layers, projection info, etc. But when I try to add them to the map the layers just appear blank (and do not have default extents that I can zoom to). You can try it yourself by adding a WMS server in QGIS with the 'CONNECTION' url in the sample mapfile below, then try adding one or more layers from it...the layers will appear in the layer control in QGIS, but no data will appear in the map. Using the sample mapfile below, I was able to use MapServer as a local proxy for the WMS service. By connecting QGIS to the wms_onlineresource metadata parameter below, I am able to get the Ortho Imagery displayed from the Toronto WMS service.

Based on this, MapServer clearly doesn't have a problem requesting data from the Toronto WMS service. QGIS in turn is able to use MapServer. However, although this can serve as a workaround, it isn't an ideal solution. It appears that this is a problem with the ability of QGIS to interoperate directly with the Toronto WMS service. I checked with the users list first, and it was recommended that this be reported here.

/path/to/wms.map:

MAP
NAME "Toronto [[OrthoImagery]] (proxy)" 
STATUS ON

SIZE 1024 1024
EXTENT 292998.8237 4824999.2385 336000.8237 4858001.2385
UNITS meters

PROJECTION
"init=epsg:2019" 
END

IMAGECOLOR 255 255 255
TRANSPARENT ON

WEB
METADATA
'wms_title' 'Toronto [[OrthoImagery]] (proxy)'
'wms_onlineresource' 'http://localhost/cgi-bin/mapserv?map=/path/to/wms.map&'
'wms_srs' 'EPSG:2019'
'ows_enable_request' '*'
END
END

LAYER
NAME "Ortho Imagery 50cm 2005" 
STATUS ON
TYPE RASTER
CONNECTION "http://map.toronto.ca:80/servlet/com.esri.wms.Esrimap/OrthoImagery?" 
CONNECTIONTYPE WMS
METADATA
"wms_srs" "EPSG:2019" 
"wms_name" "Ortho Imagery 50cm 2005" 
"wms_server_version" "1.1.1" 
"wms_format" "image/png" 
"wms_title" "Ortho Imagery 50cm 2005" 
END
PROJECTION
"init=epsg:2019" 
END
END
END

Associated revisions

Revision df8bd2d7
Added by Jürgen Fischer over 9 years ago

implement some workaround to support legacy WMS (fixes #3853)

History

#1 Updated by Jürgen Fischer over 9 years ago

  • Resolution set to fixed
  • Status changed from Open to Closed

Seems the extents are reported in some string way:

<LatLonBoundingBox maxy="4860000" maxx="338000" miny="4824000" minx="291000" SRS="EPSG:2019"/>

The coordinates need to be in latlon and there isn't supposed to be a SRS attribute.

The commit:a002e13f14c4ba9ff75de3bc47125128aa543037 implements some workarounds to support that WMS.

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