dhis2-devs team mailing list archive

[Jan Henrik Øverland <janhenrik.overland@xxxxxxxxx>]

On Fri, Sep 11, 2009 at 5:13 PM, Knut Staring <knutst@xxxxxxxxx> wrote:

> On Fri, Sep 11, 2009 at 11:54 AM, Jan Henrik Øverland <
> janhenrik.overland@xxxxxxxxx> wrote:
>
>> First of all, I was just talking about the geojson store folder, not
>> DHIS2_HOME/geojson where the GIS application is looking for files.
>>
>> On Fri, Sep 11, 2009 at 3:59 PM, Jason Pickering <
>> jason.p.pickering@xxxxxxxxx> wrote:
>>
>>> Possibly but IMHO, for more complex use cases, you would probably want to
>>> use something like Geoserver to automatically generate the GeoJSON for you
>>> possibly on the fly.
>>>
>>> Creating this type of directory structure, for say, the entire world
>>> would be daunting and a real pain to maintain. What I tried to do with the
>>> geodata at WHO for instance, was to flatten everything into a single layer,
>>> and then let Geoserver sort it out with the use of filters of WFS posts in
>>> order to get what you actually need. From a geodatabase management
>>> standpoint, it is much, much easier than having to maintain separate files
>>> in many different directories. However if most users of DHIS2 would be
>>> working only with a few files (admin1-4, PHU) maybe just a flat directory is
>>> enough.
>>>
>>> The ability of the client to be able to consume a GeoJSON stream from a
>>> server would probably be a better feature to focus on, with the client being
>>> able to connect to a WMS server and parse a GetFeatureRequest in order to
>>> allow either 1) population of the organization unit hierarchy (Knut's
>>> request) or 2) simply downloading of the GeoJSON file for an already
>>> populated hierarchy. A refresh feature would be good, as data can change.
>>> Otherwise, maybe the code could be altered at some point to allow the
>>> Mapping client to download the GeoJSON files directly from Geoserver without
>>> having to maintain the GeoJSON files locally. Maintenance of these GeoJSON
>>> files is going to be a bit of a headache for installations with many layers,
>>> or maybe people simply do not want to bother with it but would prefer to
>>> connect to other WMS servers out there to get their data.
>>
>>
>> No 2 is exactly what it was like a couple of months ago. We decided to
>> read local GeoJSON files instead, because we wanted to leave out Geoserver
>> to get rid of those ~50 mb. It is also a lot easier for nontechnicals to
>> receive a GeoJSON file and make use of it compared to getting a set of
>> shapefiles and not being familiar with Geoserver.
>>
>> Is it possible to dynamically produce a list of shapefiles currenty
>> available in your Geoserver installation? Like the new combo box lists the
>> available files in DHIS2_HOME/geojson ?
>>
>
> Yes - this is an important feature. Actually the GeoExt based GeoExplorer
> that Johan L. has been working on has a very nice layer selector:
> http://geoext.opengeo.org/geoexplorer/preview/
>

Then we can do both.


>
> Knut
>