how to debug LOADING_REMOTE_CONTEXT_FAILED problems?

[VladimirAlexiev]

Version

5.1.0

Question

https://github.com/EKGF/dprod/issues/90:

Trying to convert https://github.com/EKGF/dprod/blob/main/examples/data-quality/example.json with riot causes error:

riot.bat -out=trig -syntax=jsonld example.json
There was a problem encountered loading a remote context [code=LOADING_REMOTE_CONTEXT_FAILED].

The context is https://ekgf.github.io/dprod/dprod.jsonld and:

• it's served as content-type: application/ld+json (reading through the JSONLD spec, I can't see whether it should be json or ld+json but all examples use .jsonld for the context URL)
• the certificate is valid
• example.json works ok on the JSONLD Playground: https://json-ld.org/playground/

So what may be the reason for the problem?

• https://stackoverflow.com/questions/41494678/how-can-i-override-the-context-when-loading-json-ld-in-jena correctly points out that the error is generic and may encompass a whole gamut of problems
• https://github.com/apache/jena/issues/1765 shows an extra reason, eg message=Unexpected response code [403] but that reason is not printed by riot
• https://github.com/apache/jena/commit/44b5535dc47b0159a74ff93e4d41e71e3c69c4ec says removed the printStackTrace when "loading remote context failed" but that's just in a test

[afs]

Getting example.json returns an HTML document; the github display of the file. Use the "raw", the processing is all inside Titanium JSON-LD.

Internally, there is a nested stacktrace that says:

    A keyword [@context] redefinition has been detected.

My guess is that it is because of the array but I'm not a JSON-LD expert.

[VladimirAlexiev]

Thanks @afs !

The reason is context nested inside context (actually dprod.jsonld is not a context at all, it's a dumped ontology). So the Playground is more lenient than Titanium (thus Riot). But really dprod.jsonld is to blame.

Thank for the PR you made! I'll close this specific issue.

[afs]

Looks like https://github.com/filip26/titanium-json-ld/issues/348.