Support ArcGIS WMS GetFeatureInfo requests using GeoJSON format

[adube]

This patch introduces the support of WMS GetFeatureInfo requests made on WMS layers served by ArcGIS.

A GeoJSON format is used as INFO_FORMAT, since it seems to be the only one supported by ArcGIS. The format returns a layerName property for each feature, which identifies the layer it corresponds to. In order to read that information, a custom ngeo.format.ArcGISGeoJSON format is created in this patch.

How to test this patch

• run the desktop_all app
• clear all layers
• select the "Demo" theme
• remove all groups with the exception of "Externals"
• set visible the following layer: NPA localite noWFS
• zoom out / pan the map until you see the layer (yellow lines)
• click on features
• --> you should get results in the grid below

Known limitation

ArcGIS (at least with the layer used in the test above) does not return geometry. Therefore, it's hard to see where those features are as you need to remember where you clicked.

Known issue

While working on this patch, I found an issue: sometimes results are duplicated. This is not caused by this patch, therefore a separate PR should come soon to fix this.

[github-actions]

Examples: https://camptocamp.github.io/ngeo/gsgmf-1060-support-arcgis-wms-query/examples/
API documentation: https://camptocamp.github.io/ngeo/gsgmf-1060-support-arcgis-wms-query/apidoc/

[adube]

Travis is happy.

@sbrunner and/or @fredj : ready for review.

[sbrunner]

I create a new group named ESRI no WFS no Geom with tow layers in the same OpenLayer layer, to see if the layername is working, and it's not the case...

[adube]

I create a new group named ESRI no WFS no Geom with tow layers in the same OpenLayer layer, to see if the layername is working, and it's not the case...

Thanks for making this test.

I'm not sure I understand what the test is about nor what is not actually working. Would you please add more details to your explanation? What is the expected behaviour?

Trying to query that group and I can see results. I can't find where there are features on the second layer thought. Thanks.

[sbrunner]

Open:
https://camptocamp.github.io/ngeo/gsgmf-1060-support-arcgis-wms-query/examples/contribs/gmf/apps/desktop.html?lang=fr&tree_groups=OSM%20functions%20mixed%2CLayers%2CGroup%2COSM%20functions%2CExternal%2CFilters%20mixed%2CFilters%2CESRI%20no%20WFS%20no%20Geom&tree_group_opacity_Group=0.65&tree_enable_osm_scale=false&tree_group_layers_Layers=&tree_group_layers_Group=&tree_group_layers_OSM%20functions=&tree_enable_ch.swisstopo.dreiecksvermaschung=false&tree_enable_ch.swisstopo.geologie-gravimetrischer_atlas=false&tree_enable_ch.swisstopo.geologie-geotechnik-gk500-lithologie_hauptgruppen=false&tree_enable_ch.swisstopo.geologie-geotechnik-gk500-gesteinsklassierung=false&tree_enable_NPA%20localite=false&tree_enable_NPA%20localite%20noWFS=false&tree_enable_ch.bfe.solarenergie-eignung-fassaden=false&tree_enable_ch.bfe.solarenergie-eignung-daecher=false&tree_enable_osm_open=false&tree_enable_OSM%20map=false&tree_enable_osm_time_r_dp_2=false&tree_group_layers_Filters=&tree_group_layers_ESRI%20no%20WFS%20no%20Geom=&baselayer_ref=blank&tree_enable_Layer%20with%20very%20very%20very%20very%20very%20long%20name=false&tree_enable_osm_time_r_s=false&tree_enable_osm_time_v_s=false&tree_enable_osm_time_v_dp=false&tree_enable_osm_time_r_dp=false&tree_enable_osm_time_r_year_mounth=false&tree_enable_osm_time_d_year_mounth=false&tree_enable_osm_time_r_mounth_year=false&tree_enable_osm_time_v_mounth_year=false&tree_enable_long%20wms-t%20layer%20name%20name%20name%20name%20name%20name%20name=false&tree_enable_osm_time_r_dp_default=false&tree_enable_osm_time_r_s_default=false&tree_enable_osm_time_v_dp_default=false&tree_enable_osm_time_v_s_default=false&tree_enable_two_layers=false&tree_enable_ch.astra.ausnahmetransportrouten=false&tree_enable_no_wfs=false&tree_enable_ch.are.alpenkonvention=false&map_x=2529526&map_y=1158566&map_zoom=5

• Select the group ESRI no WFS no Geom
• Click on a yellow zone

I should get 2 features one on vd.npa_localite, one on vd.regime_hydrolique, and I get 4 features 2 on each layers...

[adube]

The above link returns a 404 error. Would you please provide one that uses the desktop_alt application? (that one should work)

[sbrunner]

Comment updated :-)

[adube]

Okay, I'll investigate why.

[adube]

Okay, it doesn't work indeed. We'll need to patch OpenLayers to make the format do the same thing as the WMS GetFeatureInfo one, however this property is vendor-param, i.e. layerName is not an official property supported by the GeoJSON spec: https://tools.ietf.org/html/rfc7946

@fredj I suggest that we implement new options in the OpenLayers "GeoJSON" format:

• layerProperty, which would be given the value "layerName"
• layers, which would act exactly like the option of the same name in WMS GetFeatureInfo.

Please, let me know what you think about this.

[fredj]

@adube could it be done by extending the GeoJSON class from OL ?
I think it would be a good start to create a custom class (ArcGISGeoJSON or GeoJSONGetFeatureInfo ?) in src/format

[adube]

Alright, I'll try that.

[adube]

Fixed.

I've noticed an other issue. I'll create a bug/task about it, as I could reproduce it on 'master' branch: results are shown twice, i.e. they have duplicates.

[adube]

@sbrunner and/or @fredj Ready for review.

[sbrunner]

Except the duplicated issue that's looks good to me (I can't reproduce it on MapServer layers).

[sbrunner]

Can you rebase on master, I think that the Travis is solved here: 24b8625

[adube]

This patch is already up-to-date onto master.

[adube]

Trying "commit --amend" for the 3rd time.

[adube]

Travis is always failing... Please, let me know if you come up with a fix so that I can rebase onto it. Thanks.

[adube]

@sbrunner and/or @fredj Travis is happy. Ready for review!

[sbrunner]

Same than before: Except the duplicated issue that's looks good to me (I can't reproduce it on MapServer layers).

[adube]

Same than before: Except the duplicated issue that's looks good to me (I can't reproduce it on MapServer layers).

• Open: https://camptocamp.github.io/ngeo/master/examples/contribs/gmf/apps/desktop_alt.html?dim_FLOOR=*&lang=en&baselayer_ref=blank&baselayer_opacity=100&tree_enable_ch.swisstopo.dreiecksvermaschung=true&map_x=2525728&map_y=1146287&map_zoom=5&tree_groups=External
• Open your browser Developer Tool, under Network
• Click on a red line
• You'll see 4 records in the results below the map, but if you inspect the query result in the Network tab there are 2
• This is a MapServer layer that uses msGMLOutput, on master

[sbrunner]

Effectively, it should be fixed but it can be in another PullRequest :-)
@fredj can you do a review of the code, for me it's ready :-)

[fredj]

Looks very good, thanks