triples with aliased @id and @base are missing at root level

[jmvanel]

Describe the bug
Two triples corresponding to @id "id" : "54141546" at root level in the JSON are lost.
Both @id 's are associated to a @base .
So there is just one triple left, corresponding to the inner JSON block :

<https://www.inaturalist.org/users/3295956>
  <http://xmlns.com/foaf/0.1/img> 
    <https://static.inaturalist.org/attachments/users/icons/3295956/thumb.jpg?1594113662>

(works fine with Distiller & JS-LD Playground)

To Reproduce
Prepare files

echo '{
  "uri" : "54141546" ,
  "description" : "Aucune fleur ou fruit, glauque",
  "user" : {
    "id" : "3295956",
    "icon" : "https://static.inaturalist.org/attachments/users/icons/3295956/thumb.jpg?1594113662"
  } }' > test-bug-OK.json
echo '{ "@context": {
  "foaf": "http://xmlns.com/foaf/0.1/",
  "rdfs" : "http://www.w3.org/2000/01/rdf-schema#" ,
  "@base" : "https://api.inaturalist.org/v1/observations/" ,  
  "uri": "@id",
  "description" : "rdfs:comment" ,
  "user" : {
     "@id": "foaf:maker",
     "@context": {
      "icon" : { "@id": "foaf:img", "@type": "@id" } ,
      "@base" : "https://www.inaturalist.org/users/" ,
      "id" : "@id"
    }
  }
} }' > test-bug.context-OK.jsonld

Java code

String dir = "file:////home/jmv/test/"
String uri = dir + "test-bug-OK.json";
String context = dir + "test-bug.context-OK.jsonld";
JsonLdOptions options = new JsonLdOptions();
options.setExpandContext(context);
System.println(  JsonLd.toRdf( uri ) . options(options) . get() )

Expected behavior
Like with Distiller:

<https://api.inaturalist.org/v1/observations/54141546> <http://xmlns.com/foaf/0.1/maker> <https://www.inaturalist.org/users/3295956> .
<https://api.inaturalist.org/v1/observations/54141546> <http://www.w3.org/2000/01/rdf-schema#comment> "Aucune fleur ou fruit, glauque" .
<https://www.inaturalist.org/users/3295956> <http://xmlns.com/foaf/0.1/img> <https://static.inaturalist.org/attachments/users/icons/3295956/thumb.jpg?1594113662> 

Additional context
NOTE : to be able to test I commented out the faulty Java code that prevents use of file: URL's , see preceding issue .

[filip26]

possibly fixed by #68

[filip26]

@jmvanel please verify, the attached test passes. thank you.

[jmvanel]

@jmvanel please verify, the attached test passes. thank you.

Alas, no, the original problem remains.
I saw you added the data of original issue as a test, but the test suite says:

Tests run: 1890, Failures: 0, Errors: 0, Skipped: 271

[filip26]

I'm sorry, but I cannot reproduce the issue. I run the test manually as well. Please feel free to update test 61

(the test suite includes 1.0 tests and non-normative tests (the skipped ones).

[filip26]

thank you, There is something wrong if a context is referenced by URI.

btw. you can use this to print RdfDataset to System.out

(new NQuadsWriter(new PrintWriter(System.out))).write(result);

[filip26]

The issue is that @base is not processed if a context is remote, it's related to issue #63

A workaround is to set the base manually. e.g.

JsonLd.toRdf("file:/...").context("file:/...").base("https://api.inaturalist.org/v1/observations/").get()

[filip26]

The specification states:

If context is a string, it represents a reference to a remote context. 
...
Please note that @base is ignored when processing remote contexts.

See 4.1.1 Overview

and

If the expandContext option in options is set, update the active context using 
the Context Processing algorithm, passing the expandContext as local context

See expand() 6.

In your case an array containing one URL (the file:/... represented as a string) is passed to Context Processing algorithm as a local context and is processed by a step 5.2.

Question about base and remote contexts suggests to remove @base after step 5.2.5.2 which is a step right after the given URL has been deferrenced.

I tend to close this issue and recommend to set a base explicitly as suggested above, please feel to re-open, to put more light on this.