[Qgis-user] Accessing QGIS's log of errors? Issues with a WMS provider with QGIS 1.7.4 on MacOS X

Thu Apr 19 05:35:36 PDT 2012

Hi Etienne,

Thanks a lot for the detailed followup! As a mere QGIS user, I don't 
feel comfortable to build it from source.

In the log that you shared with us, I don't see any clue pointing to 
what could be the reason for the error. Did you get that
	"Map request error : Response: ?PNG"
dialog box? That's the error I get and trying to fix.

While the WMS errors were recently improved 
(http://lists.osgeo.org/pipermail/qgis-commit/2011-April/006800.html ), 
this is still a cryptic error message from QGIS.

Thanks for any further feedback!

Alex

Alexandre Leroux, M.Sc., ing.
MSC Data Management Section /
Section de gestion des données du SMC
Canadian Meteorological Centre / Centre météorologique canadien
Environment Canada / Environnement Canada
alexandre.leroux at ec.gc.ca - (514) 421-5024

On 04/18/12 14:26, Etienne Tourigny wrote:
> Alexandre.
>
> First thing to look at is the "Log Messages" panel, but in this case
> it shows nothing.
>
> The proper way to see (very) verbose error output is to compile QGis
> in "Debug" mode.
> Basically you need to add the following option to cmake:
> -DCMAKE_BUILD_TYPE=Debug
>
> More details at http://hub.qgis.org/wiki/quantum-gis/Building_QGIS_with_CMake
> For OSX specific info, see http://www.kyngchaos.com/macosx/index
>
> I am not sure if there are debug builds out there...
>
> Attached is the error log when adding a png layer from your server
>
> Here is the most relevant part:
>
> Debug: src/providers/wms/qgswmsprovider.cpp: 507: (draw) getmap:
> http://wms.weatheroffice.gc.ca/geomet/?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&BBOX=-179.000000,27.988827,-39.000000,80.000000&SRS=EPSG:4326&WIDTH=1024&HEIGHT=380&LAYERS=CAPA.6P_PR&STYLES=PRECIPCM&FORMAT=image/png&DPI=96&TRANSPARENT=TRUE
> Debug: src/core/qgsnetworkaccessmanager.cpp: 61: (queryProxy) using
> user proxy for http://wms.weatheroffice.gc.ca/geomet/?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&BBOX=-179.000000,27.988827,-39.000000,80.000000&SRS=EPSG:4326&WIDTH=1024&HEIGHT=380&LAYERS=CAPA.6P_PR&STYLES=PRECIPCM&FORMAT=image/png&DPI=96&TRANSPARENT=TRUE
> Debug: src/providers/wms/qgswmsprovider.cpp: 710: (readBlock) image
> height = 380 bytesPerLine = 4096
> Debug: src/core/raster/qgsrasterlayer.cpp: 4813: (createNextPartImage) Entered
> Debug: src/core/raster/qgsrasterlayer.cpp: 4840: (createNextPartImage)
> mCurrentPartRasterMin = 0
> Debug: src/core/raster/qgsrasterlayer.cpp: 4841: (createNextPartImage)
> imageX = 25 imageY = 242
> Debug: src/core/raster/qgsrasterlayer.cpp: 4852: (createNextPartImage)
> mCurrentPartRasterMax = 380 mViewPort->drawableAreaYDim = 380
> Debug: src/core/raster/qgsrasterlayer.cpp: 959: (draw) raster draw
> time (ms): 207
> Debug: src/core/raster/qgsrasterlayer.cpp: 794: (draw) exiting.
> Debug: src/core/qgsmaprenderer.cpp: 514: (render) Layer rendered without issues
> Debug: src/core/qgsmaprenderer.cpp: 554: (render) Done rendering map layers
> Debug: src/core/qgspallabeling.cpp: 1108: (drawLabeling) LABELING
> work:  0 ms ... labels# 0
> Debug: src/core/qgspallabeling.cpp: 1231: (drawLabeling) LABELING draw:  0 ms
> Debug: src/core/qgsmaprenderer.cpp: 632: (render) Rendering completed
> in (seconds): 0.224
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 608 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 1632 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 2656 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 3680 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 4704 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 5728 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 7776 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 9824 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 10848 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 1098:
> (cacheReplyProgress) 11382 of 11382 bytes of map downloaded.
> Debug: src/providers/wms/qgswmsprovider.cpp: 911: (cacheReplyFinished)
> contentType: IMAGE/PNG
> Debug: src/app/qgscustomization.cpp: 778: (customizeWidget) objectName
> = QgsMessageViewer event type = 17
> Debug: src/app/qgscustomization.cpp: 780: (customizeWidget)
> QgsMessageViewer x QDialog
>
> Etienne
>
>
> On Wed, Apr 18, 2012 at 10:10 AM, Alexandre Leroux
> <alexandre.leroux at ec.gc.ca>  wrote:
>>
>> Hi list!
>>
>> I'm getting an error message when trying to display a WMS layer from a
>> specific provider with QGIS 1.7.4 on MacOS X. The GetCapabilities works fine
>> but when adding a layer, I get a cryptic short error message with "PNG???"
>> or "JPEG???".
>>
>> My question: is there any way I can access QGIS verbose error logs?
>>
>> I'd like to understand (and thus fix) what's wrong. I suspect it's our WMS
>> server that is not behaving correctly, but it does work with several other
>> software such as OpenLayers, ArcGIS, MapInfo, etc. So far, only QGIS on
>> MacOS X fails (it appears to work fine on QGIS on Windows) to load WMS
>> layers from this server (other WMS servers appear to work fine in the MacOS
>> X version of QGIS).
>>
>> For those curious to test, here's the WMS server:
>> http://wms.weatheroffice.gc.ca/geomet/?service=WMS&request=getCapabilities
>>
>> It's on WeatherOffice, one of the most visited websites in Canada (don't we
>> all like to know how to dress in the morning ;-) and I'd like to direct
>> users of our WMS to QGIS in the official documentation, but I first need
>> QGIS to work fine with our WMS server!
>>
>> Thanks for any feedback -
>>
>> Alex - Slashgeo.org
>> --
>> Alexandre Leroux, M.Sc., ing.
>> MSC Data Management Section /
>> Section de gestion des données du SMC
>> Canadian Meteorological Centre / Centre météorologique canadien
>> Environment Canada / Environnement Canada
>> alexandre.leroux at ec.gc.ca - (514) 421-5024
>> _______________________________________________
>> Qgis-user mailing list
>> Qgis-user at lists.osgeo.org
>> http://lists.osgeo.org/mailman/listinfo/qgis-user