CRS info added in WMS GetFeatureInfo requests

[nprigour]

During WMS GetFeatureInfo requests CRS (for WMS version 1.3.0) or SRS (for WMS version 1.1.1) are not provided in the request URL. This may cause problem when retrieving layer information (see also #316 for a more analytical description of the problem)

Signed-off-by: Nikolaos Pringouris nprigour@gmail.com

[fgdrf]

Not really sure about this change, because @jodygarnett fixed getFeatureInfo Request a while ago (ec012ac) for WMS 1.3.0 requests, where this line has been commented.

@jodygarnett Any ideas why?

[nprigour]

A while ago is almost 6 years back! Geotools have undergone several changes since then.
The only thing that the proposed patch does is to set the CRS parameter (for WMS version 1.3.0 compliant request) or the SRS parameter (for older WMS versions).
Currently this parameter is never sent for GetFeatureInfo requests and I do not know whether this is strictly compliant with the WMS standard. All other information i.e. BBOX (in north-east or east-north direction depending on the value of CRS) are more or less properly set in the request.
I verified behavior against geoserver 2.13 example layers and seems that behavior is correct for both WMS1.3 and WMS 1.1.1 requests. Maybe somebody can check the proposed patch against a MapServer installation to ensure that the problem is addressed

[fgdrf]

Can we cleanup commented line 211 with this pull request?

[nprigour]

I think yes. I let it there just because it was from the initial committer

[nprigour]

@fgdrf do you want to remove it?

[nprigour]

Hi @fgdrf ,

How should we proceed with this PR?

[fgdrf]

Wondering if there is a demo server for mapserver that supports WMS 1.3 out there. I'd like to test against before merging it. I do not expect any issues but lets verify first ..

[nprigour]

Try the following:

http://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&VERSION=1.1.1 (for wms 1.1.1 requests)
http://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&VERSION=1.3.0 (for wms 1.3.0 requests)
if you then load i.e. the world cities layer and try the info tool (prior to applying the PR) you will get a service exception indicating:
WMS server error. Missing required parameter SRS (or CRS) depending on the version type of the request
If the PR has been applied the getFeatureInfo request returns succesfully and information about the selected city is displayd in infoView.

[fgdrf]

Hmm, its working not as stable as expected. I was able to get information for Paris only once. Afterwards no information is shown in Information view. However I only tested with build applictaion and haven't debuged into getFeatureInfo Requests and Responses ..

Any ideas?

[nprigour]

Hi @fgdrf,
I do not have any issues retrieving information for the various cities. It works as expected at least for version 1.1.1 requests. If you check the java console then you will see the requests sent in the following form:
http://demo.mapserver.org/cgi-bin/wms?Y=210&X=512&SERVICE=WMS&INFO_FORMAT=text/html&LAYERS=cities&FORMAT=image/png&HEIGHT=562&REQUEST=GetFeatureInfo&WIDTH=806&BBOX=-26.509857726305366,28.92384602977667,19.297259711417066,60.86379640198511&STYLES=default&SRS=EPSG:4326&QUERY_LAYERS=cities&VERSION=1.1.1 (Note the SRS=EPSG:4326)

Now if used version 1.3 then getFeatureInfo requests are also sent in the following form:
http://demo.mapserver.org/cgi-bin/wms?SERVICE=WMS&INFO_FORMAT=text/html&LAYERS=cities&CRS=EPSG:4326&FORMAT=image/png&HEIGHT=562&J=446&REQUEST=GetFeatureInfo&I=246&WIDTH=806&BBOX=-83.43244956259832,-14.396169602825854,-5.934758141128093,39.64068223199584&STYLES=default&QUERY_LAYERS=cities&VERSION=1.3.0 (Note the CRS=EPSG:4326)
However in the 1.3 version in most cases no information is displayed in info view or if displayed it corresponds to a wrong city. I assume that is because the mapserver is configured to work with version 1.1.1.
All in all, this does not prohibit us from verifying correct behavior of sent requests in both cases (if CRS or SRS are not provided an error is returned).
I am testing in windows machine via eclipse IDE.

[fgdrf]

I expected a reproducable behaviour for the same city (in this cas Paris). However, I checked with second URL and replaced parameter CRS with SRS or even removed it and server responsed an error. With parameter CRS it doesn't and works as expected

I going to write an unit test to verify CRS is set for GetFeatureInfo Requests if version is 1.3.0

[nprigour]

Hi @fgdrf ,

Any progress on this PR?

[fgdrf]

I going to write an unit test to verify CRS is set for GetFeatureInfo Requests if version is 1.3.0

Hi @fgdrf ,

Any progress on this PR?

I started to write a test but its harder than expected to mock this with EasyMock. Sorry to say but I stoped a while ago (lack of time :()..

Can you help here and provide a test to verify that uDig adds CRS parameter for version 1.3.0 requests...?