[Qgis-developer] Adding default OSM backround maps

[Jorge Gustavo Rocha]

Hi Paolo,

I can help on this.

1. The UserAgent is already a configurable feature in QGIS (under
Options/Network). Any user can change it, but we can propose another
default value.

2. The QGIS community is very much aware of OpenStreetMap. If we really
need to make our users more aware, does it make sense to add a new
button to QGIS to report map errors? (context dependent, when the
OpenStreetMap layer is shown) It would have the same functionality of
the notes in OpenStreetMap web interface.

3.1 On the "add layer" dialog, we can show the OpenStreetMap url (which
might change over time) and licenses (for data and tiles) taken from
settings or an (external) resource. We can make this not hard coded, to
be modified easily, without upgrading QGIS. We can also check if the
service is enabled for us, before allow users to add that layer (related
with 4.).

3.2 When the tiles are used in the composer or on the web client, we can
not enforce an attribution string. We might add or suggest it, but users
should be free the create and edit the attributions. It the
responsibility of the user, not a QGIS responsibility.

4. We have to handle when tiles are not loading, either because there
are network problems, server busy, etc. We can customize the user's
feedback regarding the load of the default OpenStreetMap tiles. But we
definitely need to know formally when they shut our access down. This is
related with 3.1 issue. If the access is disabled, we can also disable
adding default OpenStreetMap tiles option.

Regards,

Jorge Gustavo

Às 09:52 de 21-03-2017, Paolo Cavallini escreveu:
> Hi all,
> we have been exploring the possibility of adding default XYZ maps to
> QGIS, so to make life far easier for users.
> The good news is that the OSM board is quite positive about this.
> The not-so-good news is that their (I believe reasonable) requirements
> imply some more development from our side.
> Is anyone interested in taking this?
> Requirements below.
> All the best.
> ===
> 
> 1. You seem to be using an user agent of "Mozilla/5.0 QGIS/2.18.3". We
> strongly recommend that you don't pretend to be a browser by adding the
> "Mozilla" bit. OpenStreetMap sees increasing traffic from "fake" user
> agents, and it is likely that we will penalise user agents like that at
> some point in the future - meaning tiles will still be served, but
> slower than to "honest" user agents that don't pretend to be a browser
> when they are not. We understand that this is difficult terrain and that
> other data sources might actually *require* that you pretend to be a
> browser - perhaps per-datasource overrides of the user agent are a
> possibility.
> 
> 2. As you know, OpenStreetMap thrives on contributions by mappers, and
> one of the main reasons we make our tiles freely available is the hope
> of attracting new contributors. It would be nice if QGIS could do its
> part to help us here, by making their users aware that OSM is open for
> everyone to contribute. Perhaps a link to
> http://www.openstreetmap.org/fixthemap can be placed somewhere in the
> layer description or something.
> 
> 3. Our data is licensed under ODbL 1.0, and our map tiles are CC-BY-SA
> 2.0. The latter could change at any time; the former is
> relatively constant.
> 
> The legal consequences of this situation for your users are:
> 
> * If they publish an image in which our tiles are visible, they must
> attribute OpenStreetMap as the source, and specify that the map image is
> CC-BY-SA 2.0, and specify that the data behind it is ODbL 1.0. All these
> requirements can be fulfilled in one go by linking to
> www.openstreetmap.org/copyright but there is no legal requirement to
> link to that page.
> 
> * Everyone is allowed to create derivatives of OpenStreetMap data - for
> example by tracing features on the OSM tiles - and freely distribute
> them. Such derived datasets, unless they are "insubstantial"
> (https://wiki.osmfoundation.org/wiki/Licence/Community_Guidelines/Substantial_-_Guideline)
> inherit the ODbL license and must, when publicly used, on request be
> made available under ODbL.
> 
> 4. If the load coming from QGIS should be unexpectedly high and impact
> our service performance, there might come a time where we'd have to
> throttle or even switch off this access. You should have some mechanism
> or plan that deals with that to avoid frustration among your user base -
> maybe a mechanism where QGIS installations request updated tile sources
> from a central service so you could notify them of the OSM tiles not
> being available (or being available elsewhere) should the need arise.
> 

J. Gustavo
-- 
Jorge Gustavo Rocha
Departamento de Informática
Universidade do Minho
4710-057 Braga
Tel: +351 253604480
Fax: +351 253604471
Móvel: +351 910333888
skype: nabocudnosor