QGIS » QGIS Application

The WMS references in the projects times out...

But thanks for that - that way I notices that the network time outs didn't work :)

Jürgen Fischer wrote:

The WMS references in the projects times out...

Yes, that server is down until next week, anyway you can test with any server

But thanks for that - that way I notices that the network time outs didn't work :)

Jürgen Fischer wrote:

The WMS references in the projects times out...

it works again

The bug in master (will be 2.1), i.e. crash if format is feature and OTFR is no was fixed by commit 96bd7e7, see #8724.

This issue should be probably divided in two, because the issues with 1.8 and 2.0/master are different.

Radim Blazek wrote:

The bug in master (will be 2.1), i.e. crash if format is feature and OTFR is no was fixed by commit 96bd7e7, see #8724.

This issue should be probably divided in two, because the issues with 1.8 and 2.0/master are different.

this ticket is really about the wrong identify result issue. At some point I was just saying that because of the crash I wasn't able to prove the issue on qgis 2.0.

Giovanni Manghi wrote:

this ticket is really about the wrong identify result issue. At some point I was just saying that because of the crash I wasn't able to prove the issue on qgis 2.0.

OK, in that case the target version should be lowered to 1.8, but there is no such version in the options.

Giovanni Manghi wrote:

I confirm that identify WMS layer seems broken in 2.0.1/master

Add this layer (postos de vigia)
crs=EPSG:3763&featureCount=10&format=image/png&layers=Postos%20de%20Vigia&styles=&url=http://mapas.dgterritorio.pt/wms/crif

from this server
http://mapas.dgterritorio.pt/wms/crif

in a new project, in one of the proposed CRSs and no reprojection.

• on qgis 1.8 indentify works
• on qgis 2.0.1/master the identify does not find anything

tested also with
http://wms.pcn.minambiente.it/ogc?map=/ms_ogc/WMS_v1.3/raster/DTM_75M.map

see also #8724-17

(identify of reprojected wms layer is wrong).

Radim Blazek wrote:

The bug in master (will be 2.1), i.e. crash if format is feature and OTFR is no was fixed by commit 96bd7e7, see #8724.

This issue should be probably divided in two, because the issues with 1.8 and 2.0/master are different.

Hi Radim,

I added a new description/title to this ticket to makes things a little more clear. It seems that overall things are ok. The only remaining issue seems to be with reprojected point layers: the identify does not return any result. reprojected Polygons are ok (rasters too), not sure about lines.

Confirmed for points and lines and fixed. Identify tool is now using as context 1x1 pixel box reprojected to layer CRS. WCS was modified accordingly to effectively use cache for identify with small context size.

Good to know:

WMS 1.1 specification:
The behavior described above is geared toward the picture case. In the graphic element case, the semantics of GetFeatureInfo are less defined. The intent is to gain experience with this version of the request and perhaps provide additional rigor in future versions of the specification.

The actual semantics of how a WMS decides what to return more information about, or what exactly to return is left up to the WMS provider.

WMS 1.3 specification:
The actual semantics of how a WMS decides what to return more information about, or what exactly to return, are left up to the WMS provider.

UMN Mapserver is using for vector point/line layers features search the pixel specified in request plus buffer around specified by TOLERANCE (layer param).

I do not have time to test also rasters... but it would be needed because it was an issue in the past (wrong pixel value for reprojected wms layers) and it could be again.

Giovanni Manghi wrote:

3) mapserver 6.4.1

when identifing on mapserver 6.4.1 (using the default modes "text/plain" and "GML" server side), the attributes show only for the "feature" mode (client side), not for "text".

GetFeatureInfo response for text/plain is not empty?

Regarding points/lines with OTFR. The WMS GetFeatureInfo does not work with a coordinate in CRS, it works with extent + width/heigh + pixel coordinate within that extent. We call the extent + width/height a context in QGIS. If OTFR is on, QGIS is using as extent a single pixel size rectangle around the point reprojected to WMS source CRS. Because it is known, that Mapserver does not work with 1x1, the WMS provider adds another pixel in width and height. That was working with 6.0.3. Not sure if Mapserver changed or it is not always sufficient.

Could you try to take the GetFeatureInfo request and modify it by hand and test in browser adding more pixels around the point to find what buffer around the point is necessary?

Another thing to test is TOLERANCE param in mapfile.

Is it available a public server for testing?

Which source data and client CRS?

Regarding QGIS WMS server, it has no sense to do any debugging on client side until #9896 (GetFeatureInfo search radius) is resolved.

You can use this public server.

http://www502.regione.toscana.it/wmsraster/com.rt.wms.RTmap/wms?map=wmsambamm

Use the Layer
rt_ambamm.idcomuni.rt.poly

The original source is in EPSG::3003

you can request in wms 1.1.1 or wms 1.3.0

the available CRS are:
EPSG:25832 EPSG:3003 EPSG:4326 EPSG:3857 EPSG:32632

To test this ticket I suggest you try to identify near a boundary better if it is a boundary of three polygons,
so you can see better if the result is on a polygon or in the near polygon.

Also
this is a sample of request getfeatureinfo:

http://www502.regione.toscana.it/wmsraster/com.rt.wms.RTmap/wms?map=wmsambamm&language=ita&SERVICE=WMS&VERSION=1.3.0&REQUEST=GetFeatureInfo&BBOX=1617043.371614,4810657.326353,1617576.552829,4810931.280957&CRS=EPSG:3003&WIDTH=581&HEIGHT=437&LAYERS=rt_ambamm.idcomuni.rt.poly&STYLES=&FORMAT=image/png&QUERY_LAYERS=rt_ambamm.idcomuni.rt.poly&FEATURE_COUNT=10&INFO_FORMAT=text/html&I=240&J=200

The request is a standard wms 1.3.0 request. It ask for a BOX with a declared coordinate of 1617043.371614,4810657.326353,1617576.552829,4810931.280957 in epsg:3003.
Most important are the parameter I & J they are the point in pixel unit in the declared box where the mause click on the GIS client.

In this request , the response return an html page but in the superior part of it you can see the coordinate in epsg:3003 and in geographics.
So you can compare it with your results.

A.

testes were made adding the layers in a projected CRS (3763, is the one defined for the layers) and then reprojecting to WGS84. The dataset (and projects and mapfiles) will be sent privately.

vectors

1) qgis 2.2/master as client, qgis 2.2 as server

http://148.251.4.143/cgi-bin/qgis_mapserv.fcgi?map=/home/gmanghi/public_html/testes_wms/project_qgis_22_vectors.qgs

Identify works for vector layers if otfr is OFF or if is ON, but no actual reprojection is made

If otfr is ON and layers are reprojected then identify of points and lines features does not work. The identify window opens but then the result are empty. Polygons identify works.

2) qgis 2.2/master as client, qgis 2.2 as server

http://148.251.4.143/cgi-bin/qgis_mapserv.fcgi?map=/home/gmanghi/public_html/testes_wms/project_qgis_22_vectors.qgs

if I identify a feature and change the mode to "feature" the result is empty (probably because qgis server does not support it, ok). If the user closes the identify window and try identify again then nothing happens and in the bottom left corner of qgis main windows shows a "no features at this position found" message. Then is necessary to remove and add again the layer to get the identify work again.

3) qgis 2.2 as client, mapserver 6.4.1 as server

http://148.251.4.143/cgi-bin/mapserv?map=/home/gmanghi/public_html/testes_wms/project_mapserver_641_vectors.map

TOLERANCE helps a lot for points and lines.

With reprojection OFF or ON identify is ok but only for "feature" mode (I have not tested to configure the HTML response server side, but I assume is ok).

"Text" mode always return no attributes, but this may not be a QGIS issue after all, in fact here

http://mapserver.org/ogc/wms_server.html#setup-a-mapfile-for-your-wms

there is an example where the text getfeatureinfo does not work too

http://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&BBOX=-11.332970,24.121208,47.584718,57.965035&SRS=EPSG:4326&WIDTH=1001&HEIGHT=575&LAYERS=cities&STYLES=&FORMAT=image/png&TRANSPARENT=true&QUERY_LAYERS=cities&INFO_FORMAT=text/plain&X=229&Y=280

while html/gml are ok

http://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&VERSION=1.1.1&REQUEST=GetFeatureInfo&BBOX=-11.332970,24.121208,47.584718,57.965035&SRS=EPSG:4326&WIDTH=1001&HEIGHT=575&LAYERS=cities&STYLES=&FORMAT=image/png&TRANSPARENT=true&QUERY_LAYERS=cities&INFO_FORMAT=text/html&X=229&Y=280

4) qgis master as client, mapserver 6.4.1 as server

http://148.251.4.143/cgi-bin/mapserv?map=/home/gmanghi/public_html/testes_wms/project_mapserver_641_vectors.map

Identify does not works at all, regardless if reprojection in OFF or ON, it always returns "no features at this position found".

rasters

1) qgis 2.2/master as client, qgis 2.2 as server

http://148.251.4.143/cgi-bin/qgis_mapserv.fcgi?map=/home/gmanghi/public_html/testes_wms/project_qgis_22_rasters.qgs

Identify works ok regardless if otfr in OFF or ON.

2) qgis 2.2/master as client, mapserver 6.4.1 as server

http://148.251.4.143/cgi-bin/mapserv?map=/home/gmanghi/public_html/testes_wms/project_mapserver_641_rasters.map

Identify works ok regardless if otfr in OFF or ON.

Giovani - can you please test that the identify tool plugin works with wms rasters?

Etienne Tourigny wrote:

Giovani - can you please test that the identify tool plugin works with wms rasters?

it is a python plugin available in the plugin repo?

Giovanni Manghi wrote:

testes were made adding the layers in a projected CRS (3763, is the one defined for the layers) and then reprojecting to WGS84. The dataset (and projects and mapfiles) will be sent privately.

Giovanni, thanks for exhaustive and well documented tests, I'll try to address all remaining problems.

vectors

1) qgis 2.2/master as client, qgis 2.2 as server

http://148.251.4.143/cgi-bin/qgis_mapserv.fcgi?map=/home/gmanghi/public_html/testes_wms/project_qgis_22_vectors.qgs

Identify works for vector layers if otfr is OFF or if is ON, but no actual reprojection is made

If otfr is ON and layers are reprojected then identify of points and lines features does not work. The identify window opens but then the result are empty. Polygons identify works.

Until the QGIS mapserver GetFeatureInfo search radius is fixed (#9896), it is useless to debug the client.

2) qgis 2.2/master as client, qgis 2.2 as server

http://148.251.4.143/cgi-bin/qgis_mapserv.fcgi?map=/home/gmanghi/public_html/testes_wms/project_qgis_22_vectors.qgs

if I identify a feature and change the mode to "feature" the result is empty (probably because qgis server does not support it, ok). If the user closes the identify window and try identify again then nothing happens and in the bottom left corner of qgis main windows shows a "no features at this position found" message. Then is necessary to remove and add again the layer to get the identify work again.

There were two problems:

• Feature format was not working at all probably since JSON support introduction, see also #10306, fixed in be318fe6

• QGIS server is using rather particular GML flavour, support added in c00bcb1b

3) qgis 2.2 as client, mapserver 6.4.1 as server

http://148.251.4.143/cgi-bin/mapserv?map=/home/gmanghi/public_html/testes_wms/project_mapserver_641_vectors.map

TOLERANCE helps a lot for points and lines.

With reprojection OFF or ON identify is ok but only for "feature" mode (I have not tested to configure the HTML response server side, but I assume is ok).

"Text" mode always return no attributes, but this may not be a QGIS issue after all

There are no attributes because your project_mapserver_641_vectors.map is missing

"wms_include_items"   "all" 

4) qgis master as client, mapserver 6.4.1 as server

http://148.251.4.143/cgi-bin/mapserv?map=/home/gmanghi/public_html/testes_wms/project_mapserver_641_vectors.map

Identify does not works at all, regardless if reprojection in OFF or ON, it always returns "no features at this position found".

"Feature" format was broken, it should be fixed, see #10306. For me it works with current master.

I hope that all the problems are resolved, please verify and close if it works for you.

There are no attributes because your project_mapserver_641_vectors.map is missing
[...]
in layers METADATA.

of course, sorry for that.

Giovanni Manghi wrote:

Etienne Tourigny wrote:

Giovani - can you please test that the identify tool plugin works with wms rasters?

it is a python plugin available in the plugin repo?

yes, it's one of the most popular plugins

there is a mention in this ticket that wms layers are not identified.
#4536

Radim: as you have been working on the value tool plugin before, can you test it? I don't know enough about WMS to be helpful.

Isn't it disabled in ValueTool for WMS? It should be.

The ValueTool prints value for each pixel the mouse moves over. For WMS it would mean to send a request for each pixel. If you move the mouse over the whole canvas it could mean thousands of requests in a second....

wow didn't think about that... but I added a "mouse click" option, I'll see if I can enable identify for wms layers when this option is enabled. Thanks for the info.