[MapProxy] Chance the cache using a dpi parameter from the request

[Andrea Peri]

Hi Matt,

I try to develope a simply wsgi filter following the suggests of mapproxy doc,

But It don't seem to work as I hope.
Infact the wsgi filter is executed after the request has reached the
mapproxy, so seem to be late for ac action to change the layersname.

In the config infact the order of execution is:

application = make_wsgi_app(r'/....//mapproxy.yaml')
application = FilterTochangeLayerName(application,....)

So before the mapproxy do its actions on the original layer and only
after the filter is able to change the layername, but is too late.

I try to understand if was possible to invert the two rows.
Before the filter and after the make_wsgi_app.

But it seem not possible.

I wrong something ?

Thx,
A.


2017-09-25 12:24 GMT+02:00 Matt Walker <walkermatt at longwayaround.org.uk>:
> Hi Andrea,
>
> We do something similar using a WSGI filter in front of MapProxy. In the
> filter we look for DPI parameter and update the LAYERS query string
> parameter to the appropriate layer based on it. Details of creating a WSGI
> filter for MapProxy can be found here:
> https://mapproxy.org/docs/1.10.0/auth.html. Our logic DPI logic is within
> the __call__ method.
>
> Hope that helps,
>
> Matt.
>
> On 22 September 2017 at 12:41, Andrea Peri <aperi2007 at gmail.com> wrote:
>>
>> Hi,
>>
>> I need to change the resolution of the map returned following the dpi
>> parameter from the request of the gis client.
>> To do this, I try to find a solution to use a different cache folder for
>> the same layer when the dpi from the request are different.
>>
>> I try to have 2 kind of cache. One for 90 dpi and another for 300dpi.
>> The layer should take from the 90 when the user do not put the dpi param
>> or set explicitly the dpi=90.
>> Otherwise the layer use the 300 dpi cache when the user request ask foto
>> dpi=300.
>>
>> Is this allowed with mapproxy ?
>>
>> Manu THX.
>> Andrea Peri
>>
>>
>>
>> _______________________________________________
>> MapProxy mailing list
>> MapProxy at lists.osgeo.org
>> https://lists.osgeo.org/mailman/listinfo/mapproxy
>
>
>
>
> --
> Matt Walker
> @_walkermatt



-- 
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Andrea Peri
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qwerty àèìòù
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