Unexpected relative path $ref behaviour when nearby absolute $ref

[rolfl]

Relative paths like $ref: ./somefile are expected to load the file in the same directory as the file that is being dereferenced.

This behaviour is not obvious in the example:

{
  $ref: 'mine://host/folder/path',
  root: {
    child: {
      $ref: './relativefile'
    }
  }
}

I need to find a way for the relative link ./relativefile to load a file in the same folder... but instead it looks for mine://host/folder/relativefile

When there's a "peer" $ref though in a parent element, the relative file paths become relative to the "peer" reference. This is unexpected. I am trying to find either:

• is this a bug in the code that imposes a basePath on a relative file link

or

• is there a way to "break out" of a peer basePath and force a relative $ref to be applies as a file ref relative to the enclosing file?

Here's a self-contained example of the behaviour... that throws the error Error: Error resolving $ref pointer "mine://host/folder/relativefile".

'use strict';

const parser = require('json-schema-ref-parser');

const doc = {
  $ref: 'mine://host/folder/path',
  root: {
    child: {
      $ref: './relativefile'
    }
  }
};

const resolver = {
  canRead: file => file.url.startsWith('mine://'),
  read: (file) => {
    if (file.url !== 'mine://host/folder/path') {
      throw new Error(`Should not be asked to handle ${JSON.stringify(file)}`);
    }
    console.warn(`resolved ${JSON.stringify(file)}`)
    return {
      mine: file.url
    };
  }
};

const prom = parser.dereference(doc, { resolve: { mine: resolver } });

prom.then(
  () => console.error('Expected an error to say ./relativefile does not exist'),
  err => console.error(err.stack)
);

The full output of the above code is:

/tmp$ node bugref.js 
resolved {"url":"mine://host/folder/path","extension":""}
Error: Error resolving $ref pointer "mine://host/folder/relativefile". 
"mine://host/folder/relativefile" not found.
    at $Refs._resolve (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/refs.js:152:11)
    at dereference$Ref (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/dereference.js:99:23)
    at crawl (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/dereference.js:58:26)
    at crawl (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/dereference.js:64:28)
    at dereference$Ref (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/dereference.js:112:24)
    at crawl (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/dereference.js:46:22)
    at dereference (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/dereference.js:19:22)
    at $RefParser.dereference (/tmp/node_modules/@apidevtools/json-schema-ref-parser/lib/index.js:247:5)

[JamesMessinger]

Nested $refs like that aren't currently supported. See PR #146

[philsturgeon]

I'm not sure this is particularly valid $ref usage anyhow. $ref and $id will be getting a bit of an overhaul for JSON Schema 2019-09 support, which is being handled by #145, so let's track all that work there.