Section on web services and OGC standards about geocompr

[Robinlovelace]

Hi @cvitolo it's over a year since you raised this idea and a lot has changed. We've got a complete book! Could you take a look and suggest where you think such a section would work best? I'm guessing in chapter 7 of data I/O, just before this section: https://geocompr.robinlovelace.net/read-write.html#geographic-data-packages

Thoughts? Agreed getting data from standard web services is a very useful skill and I don't think we've covered it yet. We have a window of opportunity before it gets sent to copy-editing in a few weeks!

[Robinlovelace]

Apologies for not acting on this sooner btw.

[cvitolo]

Great work!

I agree, accessing data via web service would suite section 7.2

Many thanks for taking my suggestion into account.

[Robinlovelace]

Fantastic. Another question: do you have any example data/resources/code showing how to import data from web services? Thinking a minimal reproducible example here would be most useful.

[Robinlovelace]

Downloading data from a WFS such as http://www.bgs.ac.uk/data/services/wfs.html would be very useful. Any code showing how to do that: very much appreciated, e.g. from: http://ogc.bgs.ac.uk/digmap625k_gsml32_cgi_gs/wfs?service=WFS&request=GetCapabilities&AcceptVersions=2.0.0&

[Robinlovelace]

@cvitolo please take a look here: #322

Is that the kind of content you were thinking? I'm new to OWS in R so certainly room for improvement!

[cvitolo]

Sorry for the late reply @Robinlovelace, was traveling during the past week.

In terms of OGC standards, I would mention the sos4R (An R client for the OGC Sensor Observation Service, the are plenty of examples in the manual).

There is a basic example of how to list WCS layers here: https://github.com/OpenDataHack/data_service_catalogue/blob/master/ecmwf_web_coverage_service.ipynb

Some examples of how to visualise WMS using leaflet:

• https://rstudio.github.io/leaflet/basemaps.html
• https://gis.stackexchange.com/questions/230193/wms-in-leaflet-r
• https://gist.github.com/ateucher/297a0ddc2c78306a518c4fe2063d4f11

[Robinlovelace]

Many thanks Claudia, this is very, very useful. i'll try to get something in the master branch, just in time for it being submitted for production!

[Robinlovelace]

Seems sos4R is no longer on CRAN. Any ideas why? Cc @edzer - apologies for nudge Edzer but as you'll see from #322 I'm writing a small section on web services but this is not my area of expertise. Would you recommend pointing people to sos4R and do you have any suggested resources beyond those kindly provided by Claudia above? Thanks!

[edzer]

@nuest

[eblondel]

@Robinlovelace may I suggest you look at the revision of the CRAN spatial task view i've sent some days ago? where more emphasis was given on standards: on formats first (https://github.com/r-spatial/task_views/blob/master/ctv/Spatial.ctv#L149) with stronger referencing of sf package, and services then (https://github.com/r-spatial/task_views/blob/master/ctv/Spatial.ctv#L211). On services ,distinction could be done between OGC standards and software product - specific services (API Clients). May I suggest also you look into the following packages:

• geosapi package which offers an interface to the known GeoServer open-source and its web API for management of spatial data (for which I'm in process to contribute to GeoServer official documentation with R code snippets);
• geonapi package that interfaces the legacy GeoNetwork API for metadata management, maybe in less extent, since similar management may be operated (by preference) through OGC standard and ows4R CSW R client. All these packages I refer to are published on CRAN.
  Hope this helps