How to use the latest version of Californium

[thread_yoda]

Hi, 

I am trying to following the instructions at: https://infocenter.nordicsemi.com/index.jsp?topic=%2Fcom.nordic.infocenter.iotsdk.v0.9.0%2Fiot_sdk_user_guides_java_coaps.html

but the directory paths of Californium has deviated quite a bit since this was published. Do you have some updated instructions on how to use Californium with your IoT examples?

Thanks very much. 

[Didrik Rokhaug]

Hi.

I am not aware of any updated version of that guide.

However, there doesn't seem to be too big changes in the file structure of the Californium project.

The biggest is probably that the Californium core and Scandium has been gathered into one repo: https://github.com/eclipse/californium

However, except for the top two layers, everything should be the same, and it is quite obvious what the new paths are.

The only path that I had some problems finding the modern equivalent of was californium.core/cf-secure/......./examples.

The new path seems to be https://github.com/eclipse/californium/tree/master/demo-apps/cf-secure/src/main/java/org/eclipse/californium/examples

Are there any other paths, in particular, that are giving you trouble?

Also, it is worth pointing out that you might run into worse problems than just some changed paths. There is a reason why the guide states explicitly which version it was created for.

Best regards,

Didrik

[thread_yoda]

It's the last step that I'm having trouble reconciling:

Copy the whole certs directory from
<Local Repositories>/californium.core/cf-secure/certs
to
<Local Repositories>/californium.tools/cf-client/certs

There is no certs directory, but I do see a top level demo-certs directory. But what do I copy and where? 

Yes, I realize the guide was based on an older version of the repo but there is no real reason to go back to an older version of the code. I think the guide should be updated. This is also why I am here to ask for your wisdom. :)

Thanks for additional advice you can provide as we are trying to stand up our own CoAP proxy instance and want to be able to connect Nordic Thread + CoAP examples that we have built to it instead of GCP because the GCP proxy demo is not a commercial offering.

[Achim Kraus]

> Also, it is worth pointing out that you might run into worse problems than just some changed paths. There is a reason why the guide states explicitly which version it was created for.

I'm one of the commiter of Californium. I strongly recommend not to use 5 years old stuff, use our current 2.3.0 release.

[Achim Kraus]

Have a look at Californium Proxy2 .

That documentation doesn't cover right now to use coaps/DTLS (I haven't the time to do so). But with Californium 2.3.0 it is that much easier to setup coaps/DTLS, than it was years ago. If you want your client to use PSK, it's mainly to provide the port the server is listening to and a PSKStore containing the identities and secrets. That should help to start and later you may adapt the defaults in the configuration according your environment and requirements.

[thread_yoda]

Thanks Achim! Yup, I started to just use the Californium release to get my feet wet since as you mentioned I ran into some further issues after attempting to fix the path issue.

I cloned the latest version of californium from github and I was able to successfully run the cf-helloworldserver example and I used Copper (Cu) google chrome extension to access the example hello world resource. This is working fine. 

Next, I went to run cf-secure example. This seems to run fine also. But is there a way to use Copper to test this? Or I need some other tool? 

I think it would be nice if there was some getting started guide with the latest release of californium (and preferably with Nordic Thread capable dev kits). I have further questions like where the Key store are defined and how to setup the various modes, PSK, X.509, etc. I haven't tried the californium-proxy2 but also I think this needs to be shown how to integrate with DTLS, etc.Anyway, I am trying to get some basic understanding and take the first baby steps...