[gdal-dev] ogr2ogr and WFS 2

[Hernán De Angelis]

Sorry, in the message below I meant one needs to explicitly specify 
OGR_WFS_PAGING_ALLOWED YES, with a suitable OGR_WFS_PAGE_SIZE.



Den 2021-11-30 kl. 09:34, skrev Hernán De Angelis:
> Thank you, Jukka. I did that and worked. I also had another case where 
> it is important to get this right. It is when the total number of 
> features exposed by the service exceeds the maximum number of features 
> allowed to be fetched in one request (CountDefault). In this case it 
> is also important to set the paging to NO, in addition with an 
> adequate OGR_WFS_PAGE_SIZE so that the layer can be downloaded 
> entirely, in several pages, without hitting the limit.
>
> Best
>
> Hernán
>
>
> Den 2021-11-30 kl. 08:59, skrev Rahkonen Jukka (MML):
>>
>> Hi,
>>
>> There is something about WFS 2 and paging in 
>> https://gdal.org/drivers/vector/wfs.html
>>
>> “Paging with WFS 2.0
>>
>> The WFS driver will automatically detect if server supports paging, 
>> when requesting a WFS 2.0 server. The page size (number of features 
>> fetched in a single request) is limited to 100 by default when not 
>> declared by the server. It can be changed by setting the 
>> OGR_WFS_PAGE_SIZE configuration option, or by specifying COUNT as a 
>> query parameter in the URL of the connection string.
>>
>> If only the N first features must be downloaded and paging through 
>> the whole layer is not desirable, the OGR_WFS_PAGING_ALLOWED 
>> configuration option should be set to OFF.”
>>
>> So by default normally GDAL goes to paging mode that makes it 
>> possible to read the whole featuretype, possibly restricted with BBOX 
>> or other filters but it should be possible to disable paging with 
>> --config OGR_WFS_PAGING_ALLOWED OFF. I would try that.
>>
>> -Jukka Rahkonen-
>>
>> *Lähettäjä:* gdal-dev <gdal-dev-bounces at lists.osgeo.org> *Puolesta 
>> *Hernán De Angelis
>> *Lähetetty:* maanantai 29. marraskuuta 2021 12.43
>> *Vastaanottaja:* gdal-dev at lists.osgeo.org
>> *Aihe:* [gdal-dev] ogr2ogr and WFS 2
>>
>> Dear all
>>
>> I seem to have problems understanding how ogr2ogr interacts with WFS 
>> and hope someone would be able to clarify.
>>
>> I have this WFS:
>>
>> https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?
>>
>> The capabilities document states that it supports WFS 1.0.0, 1.1.0 
>> and 2.0.0.
>>
>> If I do:
>>
>> ogr2ogr -f GPKG test.gpkg 
>> "WFS:https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?SERVICE=WFS&VERSION=1.0.0&REQUEST=GetFeature&TYPENAME=stationsregistret:active_site&MAXFEATURES=100 
>> <https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?SERVICE=WFS&VERSION=1.0.0&REQUEST=GetFeature&TYPENAME=stationsregistret:active_site&MAXFEATURES=100>"
>>
>> I get a small and nice GPKG file very fast.
>>
>> But if I do:
>>
>> ogr2ogr -f GPKG test.gpkg 
>> "WFS:https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?SERVICE=WFS&VERSION=2.0.0&REQUEST=GetFeature&TYPENAMES=stationsregistret:active_site&COUNT=100 
>> <https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?SERVICE=WFS&VERSION=2.0.0&REQUEST=GetFeature&TYPENAMES=stationsregistret:active_site&COUNT=100>"
>>
>> It downloads the whole layer.
>>
>> This behaviour can be seriously impractical for services exposing a 
>> large number of features.
>>
>>
>> Pay attention that if I do:
>>
>> curl 
>> "https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?SERVICE=WFS&VERSION=2.0.0&REQUEST=GetFeature&TYPENAMES=stationsregistret:active_site&COUNT=100" 
>> <https://stationsregister.miljodatasamverkan.se/geoserver/stationsregistret/wfs?SERVICE=WFS&VERSION=2.0.0&REQUEST=GetFeature&TYPENAMES=stationsregistret:active_site&COUNT=100>
>>
>> it retrieves a short document fast with just 100 features. The same 
>> of course if I invoke the service using WFS 1.0.0 or 1.1.0.
>>
>>
>> What is going on here? Is it me that I misunderstood something about 
>> how ogr2ogr is supposed to interact with WFS services?
>>
>> Using GDAL 3.4.0, released 2021/11/04. But the same behaviour was 
>> observed in 3.3.2.
>>
>>
>> Thanks in advance for any clarification
>>
>>
>> Hernán
>>
>>
>
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