[josm-dev] WMS requiring an EULA acceptance

[Sebastian Klein]

Pieren wrote:
> Dear josm-devs,
> 
> In my country, we have a commercial imagery supplier which is ready to open
> its images but only for the OSM project (licencing issues fixed). For that,
> they will set-up a WMS for a limited coverage during an experimental period
> and want to check that only allowed clients are accessing the data by
> checking the user-agent (on which only the OSM editors could be accepted and
> others rejected of course).
> The main concern is about a special handling of the WMS. They want that a
> contributor using the WMS the first time shall read and accept an EULA (End
> User License Agreement). Again this is just to inform people that they are
> only allowed to use the imagery for OSM and nothing else. Of course, the
> whole process can be bypassed by anyone who really want to access the WMS
> but this is a demand from the lawyers. The EULA would be available in two
> languages but could be extended later.
> Then I'm asking you to check if this demand is possible and how it could be
> solved. I don't want to fork the WMS plugin just for that, so my idea is
> that the plugin could be modified in a way that the special WMS URI could be
> identified as such in the Java code (hardcoded) and would raise the EULA
> acceptance dialog automatically the first time (stored somewhere is
> different languages). I could implement that myself but I would have your
> feedback first to see if this is the right way to go.

Generally, it should be possible to include something like this in the 
main wms plugin. Hardcoding some URLs might also be acceptable (but I 
don't think it is needed).

There are always older versions of the wms plugin out there in use. 
These older versions would not know about this "blacklist" and would 
simply ignore the EULA enforcement. You might want to demand a certain 
parameter in the URL (like ...&user=openstreetmap) just to sort out the 
older clients.

When reading the list of defaults [1], wms plugin ignores each line that 
has more than 2 semicolons in it. You can exploit this, to create your 
own custom format. E.g. the first string could be the name of the custom 
format "EULA-1.0", followed by the necessary parameters. When extending 
the plugin, make it ignore lines with unknown format.

I would imagine it like this:
* You open josm preference and select the entry from the defaults.
* A message box pops up, informing you that it is necessary to accept an 
EULA for using the service.
* If you click "OK", it would download the EULA text from an external 
website (possibly translated) and present it in another dialog.
* Save in the preferences that EULA has been accepted.

[1] 
<http://svn.openstreetmap.org/applications/editors/josm/plugins/wmsplugin/sources.cfg>

Sebastian