fixing callback reference resolving code

Author: gracekarina

modules/swagger-parser-v3/src/main/java/io/swagger/v3/parser/processors/CallbackProcessor.java

@@ -34,7 +34,7 @@ public CallbackProcessor(ResolverCache cache, OpenAPI openAPI) {
     }
 
     public void processCallback(Callback callback) {
-        if (callback.get("$ref") != null){
+        if (callback.get$ref() != null){
             processReferenceCallback(callback);
         }
         //Resolver PathItem
@@ -57,12 +57,12 @@ public void processCallback(Callback callback) {
     }
 
     public void processReferenceCallback(Callback callback ){
-        String $ref = callback.get("$ref").get$ref();
+        String $ref = callback.get$ref();
         RefFormat refFormat = computeRefFormat($ref);
         if (isAnExternalRefFormat(refFormat)){
             final String newRef = externalRefProcessor.processRefToExternalCallback($ref, refFormat);
             if (newRef != null) {
-                callback.get("$ref").set$ref("#/components/callbacks/"+newRef);
+                callback.set$ref("#/components/callbacks/"+newRef);
             }
         }
     }

modules/swagger-parser-v3/src/main/java/io/swagger/v3/parser/processors/ExternalRefProcessor.java

@@ -667,7 +667,7 @@ public String processRefToExternalCallback(String $ref, RefFormat refFormat) {
 
         if (existingCallback != null) {
             LOGGER.debug("A model for " + existingCallback + " already exists");
-            if(existingCallback.get("$ref").get$ref() != null) {
+            if(existingCallback.get$ref() != null) {
                 // use the new model
                 existingCallback = null;
             }
@@ -681,13 +681,13 @@ public String processRefToExternalCallback(String $ref, RefFormat refFormat) {
             cache.addReferencedKey(newRef);
 
             String file = $ref.split("#/")[0];
-            if(callback.get("$ref") != null){
-                if (callback.get("$ref").get$ref() != null) {
-                    RefFormat format = computeRefFormat(callback.get("$ref").get$ref());
+            if(callback.get$ref() != null){
+                if (callback.get$ref() != null) {
+                    RefFormat format = computeRefFormat(callback.get$ref());
                     if (isAnExternalRefFormat(format)) {
-                        callback.get("$ref").set$ref(processRefToExternalCallback(callback.get("$ref").get$ref(), format));
+                        callback.set$ref(processRefToExternalCallback(callback.get$ref(), format));
                     } else {
-                        processRefToExternalCallback(file + callback.get("$ref").get$ref(), RefFormat.RELATIVE);
+                        processRefToExternalCallback(file + callback.get$ref(), RefFormat.RELATIVE);
                     }
                 }
             }

modules/swagger-parser-v3/src/test/java/io/swagger/v3/parser/test/OpenAPIResolverTest.java

@@ -8,6 +8,7 @@
 import com.github.tomakehurst.wiremock.client.WireMock;
 import com.github.tomakehurst.wiremock.core.WireMockConfiguration;
 import io.swagger.v3.core.util.Json;
+import io.swagger.v3.core.util.Yaml;
 import io.swagger.v3.oas.models.Components;
 import io.swagger.v3.oas.models.OpenAPI;
 import io.swagger.v3.oas.models.Operation;
@@ -347,7 +348,7 @@ public void componentsResolver() throws Exception {
         //callback pathItem -> operation ->requestBody
         assertEquals(callbacks.get("heartbeat").get("$request.query.heartbeat-url").getPost().getRequestBody().get$ref(),"#/components/requestBodies/requestBody3");
         //remote callback ref
-        assertEquals(callbacks.get("remoteCallback").get$ref(),"http://localhost:" + serverPort + "/remote/callback");
+        assertEquals(callbacks.get("remoteCallback").get$ref(),"#/components/callbacks/callback");
 
     }