DCAT output for OCG-API Records endpoint

[alexarobu]

Hi,

We've been asked if the DCAT output of the OGC-API endpoint can be extended (i.e. the output you get if you go to something like https://osmetadata.astuntechnology.com/geonetwork/api/collections/main/items/33858d93-fd9a-4ef7-a79b-5637443fad2d?f=dcat).

I had a look at this, my initial instinct was that it's dictated by https://github.com/geonetwork/geonetwork-microservices/blob/main/modules/services/ogc-api-records/src/main/resources/xslt/ogcapir/formats/dcat/dcat.xsl, but this doesn't seem to be the case, do you know which file is responsible for that view?

Ideally, the DCAT output we'd like to get would be the SEMICeu suggested mapping (https://github.com/SEMICeu/iso-19139-to-dcat-ap/blob/main/iso-19139-to-dcat-ap.xsl)

We run the OGC-API service as a separate Docker container alongside GeoNetwork 4.2.9.

Any advice would be appreciated and if you'd like me to open a PR back into the application, please let me know, more than happy to if you think it would be useful for the wider community! 😃

[davidblasby]

Hi, Alex,

There is a new OGCAPI-Records as part of GN5 - geonetwork/geonetwork#74. I hope to get this merged pretty soon (jose is looking into it).

Francois is working on moving the GN4 formatterApi into GN5 - i think that's here - geonetwork/geonetwork#78

Francois (and jose) have done quite a bit to improve country specific DCAT-AP output from GN4 (mostly XSLT). I am looking forward to getting these in the GN5 OGCAPI-Records.

[alexarobu]

Hi David,

Thank you for your reply. Unfortunately, we are running a dockerised GeoNetwork 4.2.9, and we don't have any plans to upgrade to GN5 soon. Do you know if these changes will be backported by any chance?

[jahow]

Hi @alexarobu, how about using the DCAT formatters present in GN4? They should be available on GN 4.2.9 with #7600, and that includes the SEMIC conversion.

Then you wouldn't need the ogc-api-records microservice.

[alexarobu]

Hi Olivia, I hope you're well 🤗 Thanks for replying!

I see that the PR you linked has a label of failed backport, has that been resolved now and was it backported, do you know?

My understanding is that our client was quite interested in using his OGC-API collection alongside GeoNetwork, hence the question of where that can be improved. It could be that we take the changes from core and migrate them to the OGC microservice

[alexarobu]

The OGC-API is a bit of a blackbox to me, so I am not quite sure how to help it along 😂

[jahow]

I'm good thanks!! and you?

Yes you're right, the PR wasn't backported to 4.2.x! I assumed it had been. Well it's probably a lot of changes to backport so that might explain it.

You could try porting the SEMIC conversion to the ogc-api-records microservice, but that is probably not a trivial task and as @davidblasby said, it would come as a kind of duplicate of both GN4.4 and the work on GN5 (even though GN5 is not yet useable in production AFAIK).

[alexarobu]

I am good, thank you!! 😄

I wouldn't mind porting the conversion to the ogc-api-records microservice, but I tried and failed to locate the file(s) that dictate what gets used by the API in my example (https://osmetadata.astuntechnology.com/geonetwork/api/collections/main/items/33858d93-fd9a-4ef7-a79b-5637443fad2d?f=dcat) ☹️

We are still running 4.2.9 and will be running it for a while, we haven't tested 4.4 yet.

Same with GN5, even if it would be out, we wouldn't be looking at an upgrade for a while and even then, I think our client is still quite keen to use both sets of APIs.

[davidblasby]

Alex,

I think GN5 instead of geonetwork-microservices would be the better place to put work in. Others can chime in, however, I'm not sure how much development work is happening in geonetwork-microservices. As far as I know (I could be wrong) - most of its going into GN5.

However, if you do decide to do some work in geonetwork-microservices, the core of the new DCAT-AP stuff is the new XSLTs that Francois put in GN4. There's also quite a bit of infrastructure with the FormatterApi.

I think there's a fair amount of work that Francois put into the DCAT-AP stuff, but I would guess (!!) that it could be backported to 4.2. That's probably your best bet. However, there isn't an OGCAPI-Records implementation in GN4.

[jahow]

Backporting the DCAT formatters to 4.2 sounds like a reasonable plan but honestly @alexarobu you should look into upgrading to 4.4, it might be the cheapest option all things considered!