Add DocumentResolverTest (#132)

src/main/java/com/apicatalog/jsonld/document/DocumentResolver.java

@@ -2,6 +2,8 @@
 
 import java.io.InputStream;
 import java.util.Optional;
+import java.util.logging.Level;
+import java.util.logging.Logger;
 import java.util.stream.Collectors;
 
 import com.apicatalog.jsonld.JsonLdError;
@@ -11,6 +13,8 @@
 
 public class DocumentResolver {
 
+    private static final Logger LOGGER = Logger.getLogger(DocumentResolver.class.getName());
+
     private MediaType fallbackContentType;
 
     public DocumentResolver() {
@@ -26,7 +30,15 @@ public DocumentResolver() {
      */
     public DocumentReader<InputStream> getReader(MediaType contentType) throws JsonLdError {
         return findReader(contentType)
-                .or(() -> findReader(fallbackContentType))
+                .or(() -> {
+
+                    if (fallbackContentType != null) {
+                        LOGGER.log(Level.WARNING, "Content type [{0}] is not supported, trying again with [{1}].", new Object[] { contentType, fallbackContentType});
+                        return findReader(fallbackContentType);
+                    }
+
+                    return Optional.empty();
+                })
                 .orElseThrow(() -> new JsonLdError(JsonLdErrorCode.LOADING_DOCUMENT_FAILED,
                     "Unsupported media type '" + contentType
                     + "'. Supported content types are ["

src/main/java/com/apicatalog/jsonld/loader/FileLoader.java

@@ -36,9 +36,10 @@
 public final class FileLoader implements DocumentLoader {
 
     private final DocumentResolver resolver;
-    
+
     public FileLoader() {
         this.resolver = new DocumentResolver();
+        this.resolver.setFallbackContentType(MediaType.JSON);
     }
 
     private static final Logger LOGGER = Logger.getLogger(FileLoader.class.getName());    
@@ -99,5 +100,5 @@ private static final Optional<MediaType> detectedContentType(String name) {
         }
 
         return Optional.empty();
-    }
+    }    
 }

src/test/java/com/apicatalog/jsonld/document/DocumentResolverTest.java

@@ -0,0 +1,90 @@
+/*
+ * Copyright 2020 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.apicatalog.jsonld.document;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.io.InputStream;
+
+import org.junit.jupiter.api.Test;
+
+import com.apicatalog.jsonld.JsonLdError;
+import com.apicatalog.jsonld.http.media.MediaType;
+
+class DocumentResolverTest {
+
+    @Test
+    void test1() throws JsonLdError {
+        DocumentReader<InputStream> reader = (new DocumentResolver()).getReader(MediaType.N_QUADS);
+        assertNotNull(reader);
+    }
+
+    @Test
+    void test2() throws JsonLdError {
+        DocumentReader<InputStream> reader = (new DocumentResolver()).getReader(MediaType.JSON_LD);
+        assertNotNull(reader);
+    }
+
+    @Test
+    void test3() throws JsonLdError {
+        DocumentReader<InputStream> reader = (new DocumentResolver()).getReader(MediaType.JSON);
+        assertNotNull(reader);
+    }
+
+    @Test
+    void test4() throws JsonLdError {
+        DocumentReader<InputStream> reader = (new DocumentResolver()).getReader(MediaType.of("application", "test+json"));
+        assertNotNull(reader);
+    }
+
+    @Test
+    void test5() throws JsonLdError {
+        assertThrows(JsonLdError.class, () -> (new DocumentResolver()).getReader(MediaType.HTML));
+    }
+
+    @Test
+    void test6() throws JsonLdError {
+        DocumentResolver resolver = new DocumentResolver();
+        resolver.setFallbackContentType(MediaType.JSON);
+        DocumentReader<InputStream> reader = resolver.getReader(MediaType.of("text/plain"));
+        assertNotNull(reader);
+    }
+
+    @Test
+    void test7() throws JsonLdError {
+        DocumentResolver resolver = new DocumentResolver();
+        resolver.setFallbackContentType(MediaType.XHTML);
+        assertThrows(JsonLdError.class, () -> resolver.getReader(MediaType.of("text/plain")));
+    }
+
+    @Test
+    void test8() throws JsonLdError {
+        DocumentResolver resolver = new DocumentResolver();
+        resolver.setFallbackContentType(MediaType.ANY);
+        DocumentReader<InputStream> reader = resolver.getReader(MediaType.of("text/plain"));
+        assertNotNull(reader);
+    }
+
+    @Test
+    void test9() throws JsonLdError {
+        DocumentResolver resolver = new DocumentResolver();
+        resolver.setFallbackContentType(MediaType.XHTML);
+        DocumentReader<InputStream> reader = resolver.getReader(MediaType.of("text/plain+json"));
+        assertNotNull(reader);
+    }
+
+}