Implement Openstreetmap provider

[pjsier]

Thanks for putting this library together! I took a stab at implementing an OpenStreetMap provider here since it was listed in #1

I tried to follow the patterns from the OpenCage provider and used the builder pattern for specifying additional parameters, but I'm new to Rust so let me know if anything seems off. I'd like to use the InputBounds struct for the viewport parameter here, but wanted to check and see what the best way of restructuring that would be

[mthh]

I am not (yet !) contributor to georust/geocoding but I was wondering : shouldn't it be possible, for the user, to specify the endpoint address when creating a new Openstreetmap struct?
(since it is possible to install a local instance of Nominatim, as described on http://nominatim.org/release-docs/latest/admin/Installation/)

In fact it looks already feasible with your PR, but it will requires some boilerplate (compared to having a with_endpoint constructor for example).

[urschrei]

If you'd like to use the InputBounds struct, you'll have to either move it into lib.rs and make it pub, then re-import into opencage, or create a separate util module or similar and import it from there. I'd go with the former for now. Also, it looks like you'll have to do some of the arithmetic yourself for the OpenStreetMap bounds, since the call requires four coordinates, but InputBounds only specifies top left and bottom right – if you want to impl an additional method on InputBounds that does the arithmetic and returns an array, go for it!

[pjsier]

Thanks for clarifying! I implemented moving InputBounds into lib.rs here. It looks like the viewbox parameter in Nominatim takes the same input format as OpenCage, and it seems to be working now.

I'd also be interested in adding the ability to specify a custom endpoint, is a separate constructor the most straightforward way of doing that?

[urschrei]

I'd also be interested in adding the ability to specify a custom endpoint, is a separate constructor the most straightforward way of doing that?

Yep I'd just add a new_with_endpoint or similar impl. Up to you whether you'd like to perform any kind of validation using e.g. rust-url to ensure it's a valid URL.

[pjsier]

Great, thanks! Just made that update so this should be ready for review

[urschrei]

Looks good to me!

[urschrei]

bors r+

[bors]

Build succeeded

• continuous-integration/travis-ci/push