Hi On Thu, Jul 12, 2012 at 5:15 PM, Marco Hugentobler <[email protected]> wrote: > Hi > > In my opinion, it is better to use the Qt classes for the network requests > than curl. In QGIS, we have QgsNetworkAccessManager, which picks up > automatically the network settings from the options tab (proxy settings, > exclusion list, password, disk cache). It has nice progress reporting by > signal/slot, the possibility to interrupt the network request and a disk > cache. And the possibility to provide custom implementations for all that if > necessary. > > Like this, WFS, WPS, WMS providers, plugin installer and open layers plugin > (and third party python plugins) have a unified method to do network > requests. No need to use a different network library for each one (and the > mapping is never 1:1, there is always loss). > > So while it might be quicker (in terms of development time) to use the GDAL > provider, a standalone provider is always more native and flexible (that's > also the reason there are QGIS vector providers for postgres, wfs, gpx, > spatialite, grass while everything can be read with the OGR provider). >
Thanks Marco for filling in the background to the debate we had when developing the proposal with WorldBank/GFDRR on whether to implement the WCS provider natively or use GDAL. All of the reasons Marco mentions make extremely good sense. Regards Tim > Regards, > Marco > > Am 12.07.2012 15:51, schrieb Even Rouault: >>> >>> Yes - Radim already made a first pass implementation using GDAL WCS >>> though he said there were some problems with it - I think the most >>> critical being that it doesn't support proxy access (I am speaking >>> under correction here as I haven't looked into it in that much detail >>> myself). >> >> This should be rather easy to add. It is just a matter of setting the >> right >> option to CPLHTTPFetch() (and thus the curl library), namely : >> >> <li>PROXY=val, to make requests go through a proxy server, where val is of >> the >> form proxy.server.com:port_number >> <li>PROXYUSERPWD=val, where val is of the form username:password >> >> Note: They can also already be used by setting the GDAL_HTTP_PROXY and >> GDAL_HTTP_PROXYUSERPWD configuration options/environmenet variable, which >> will >> act on all GDAL/OGR drivers that go through the CPLHTTPFetch() function. >> >> I see Radim is already a GDAL committer, so there shouldn't be too much >> overhead >> if he wants to hack in the WCS driver. >> >>> I will let Radim comment on any other issues. I think from >>> the project perspective we don't mind too much which approach is used >>> if the result is efficient and integrates nicely into QGIS. >>> >>> Regards >>> >>> Tim >>> >>> >>> >>> -- >>> Tim Sutton - QGIS Project Steering Committee Member (Release Manager) >>> ============================================== >>> Please do not email me off-list with technical >>> support questions. Using the lists will gain >>> more exposure for your issues and the knowledge >>> surrounding your issue will be shared with all. >>> >>> Visit http://linfiniti.com to find out about: >>> * QGIS programming and support services >>> * Mapserver and PostGIS based hosting plans >>> * FOSS Consulting Services >>> Skype: timlinux >>> Irc: timlinux on #qgis at freenode.net >>> ============================================== >>> >> >> _______________________________________________ >> Qgis-developer mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/qgis-developer > > > > -- > Dr. Marco Hugentobler > Sourcepole - Linux & Open Source Solutions > Weberstrasse 5, CH-8004 Zürich, Switzerland > [email protected] http://www.sourcepole.ch > Technical Advisor QGIS Project Steering Committee > > > _______________________________________________ > Qgis-developer mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/qgis-developer -- Tim Sutton - QGIS Project Steering Committee Member (Release Manager) ============================================== Please do not email me off-list with technical support questions. Using the lists will gain more exposure for your issues and the knowledge surrounding your issue will be shared with all. Visit http://linfiniti.com to find out about: * QGIS programming and support services * Mapserver and PostGIS based hosting plans * FOSS Consulting Services Skype: timlinux Irc: timlinux on #qgis at freenode.net ============================================== _______________________________________________ Qgis-developer mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/qgis-developer
