feat: allow $ref and other URLs to be mapped to local URLs

Fixes #134

Author: rhwood

src/main/java/com/networknt/schema/BaseJsonValidator.java

@@ -83,7 +83,7 @@ private static JsonSchema obtainSubSchemaNode(JsonNode schemaNode, ValidationCon
             }
             else {
                 URL url = URLFactory.toURL(node.textValue());
-                return validationContext.getJsonSchemaFactory().getSchema(url);
+                return validationContext.getJsonSchemaFactory().getSchema(url, validationContext.getConfig());
             }
         } catch (MalformedURLException e) {
             return null;

src/main/java/com/networknt/schema/RefValidator.java

@@ -62,7 +62,7 @@ static JsonSchema getRefSchema(JsonSchema parentSchema, ValidationContext valida
 
             try {
                 URL url = URLFactory.toURL(schemaUrl);
-                parentSchema = validationContext.getJsonSchemaFactory().getSchema(url);
+                parentSchema = validationContext.getJsonSchemaFactory().getSchema(url, validationContext.getConfig());
             } catch (MalformedURLException e) {
                 InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream(schemaUrl);
                 parentSchema = validationContext.getJsonSchemaFactory().getSchema(is);

src/test/java/com/networknt/schema/UrlMappingTest.java

@@ -138,7 +138,7 @@ public void testMappingsForRef() throws IOException {
         config.setUrlMappings(getUrlMappingsFromUrl(mappings));
         JsonSchema schema = instance.getSchema(URLFactory.toURL("resource:tests/url_mapping/schema-with-ref.json"),
                 config);
-        assertEquals(0, schema.validate(mapper.readTree(mappings)).size());
+        assertEquals(0, schema.validate(mapper.readTree("[]")).size());
     }
 
     private Map<URL, URL> getUrlMappingsFromUrl(URL url) throws MalformedURLException, IOException {

src/test/resources/tests/url_mapping/schema-with-ref.json

@@ -1,21 +1,10 @@
 {
     "$schema": "http://json-schema.org/draft-04/schema#",
     "title": "json-object-with-schema",
-    "type": "object",
-    "description": "A JSON object and the schema to evaluate it against",
+    "type": "array",
     "properties": {
-        "for": {
-            "type": "object",
-            "description": "The object to evaluate"
-        },
         "schema": {
-            "$ref": "http://example.com/invalid/schema/url",
-            "description": "The Schema to evaluate the object against (using invalid URL to force failure if mapping is not correct)"
+            "$ref": "http://example.com/invalid/schema/url"
         }
-    },
-    "additionalProperties": false,
-    "required": [
-        "for",
-        "schema"
-    ]
+    }
 }