properly manage Accept header with multiple options

service/src/main/java/gov/nasa/pds/api/registry/configuration/WebMVCConfig.java

@@ -1,6 +1,8 @@
 package gov.nasa.pds.api.registry.configuration;
 
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Value;
@@ -15,6 +17,11 @@
 import org.springframework.web.servlet.config.annotation.PathMatchConfigurer;
 import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+import gov.nasa.pds.api.registry.controllers.ProductsController;
+import gov.nasa.pds.api.registry.model.api_responses.PdsProductBusinessObject;
+import gov.nasa.pds.api.registry.model.api_responses.ProductBusinessLogic;
+import gov.nasa.pds.api.registry.model.api_responses.WyriwygBusinessObject;
+import gov.nasa.pds.api.registry.model.exceptions.AcceptFormatNotSupportedException;
 import gov.nasa.pds.api.registry.view.CsvErrorMessageSerializer;
 import gov.nasa.pds.api.registry.view.CsvPluralSerializer;
 import gov.nasa.pds.api.registry.view.CsvSingularSerializer;
@@ -39,9 +46,37 @@
 public class WebMVCConfig implements WebMvcConfigurer {
   private static final Logger log = LoggerFactory.getLogger(WebMVCConfig.class);
 
+
+
   @Value("${server.contextPath}")
   private String contextPath;
 
+  private static Map<String, Class<? extends ProductBusinessLogic>> formatters =
+      new HashMap<String, Class<? extends ProductBusinessLogic>>();
+
+  static public Map<String, Class<? extends ProductBusinessLogic>> getFormatters() {
+    return formatters;
+  }
+
+  static {
+    // TODO move that at a better place, it is not specific to this controller
+    formatters.put("*", PdsProductBusinessObject.class);
+    formatters.put("*/*", PdsProductBusinessObject.class);
+    formatters.put("application/csv", WyriwygBusinessObject.class);
+    formatters.put("application/json", PdsProductBusinessObject.class);
+    formatters.put("application/kvp+json", WyriwygBusinessObject.class);
+    // this.formatters.put("application/vnd.nasa.pds.pds4+json", new
+    // Pds4ProductBusinessObject(true));
+    // this.formatters.put("application/vnd.nasa.pds.pds4+xml", new
+    // Pds4ProductBusinessObject(false));
+    formatters.put("application/xml", PdsProductBusinessObject.class);
+    formatters.put("text/csv", WyriwygBusinessObject.class);
+    formatters.put("text/html", PdsProductBusinessObject.class);
+    formatters.put("text/xml", PdsProductBusinessObject.class);
+  }
+
+
+
   @Override
   public void addResourceHandlers(ResourceHandlerRegistry registry) {
     String contextPath = this.contextPath.endsWith("/") ? this.contextPath : this.contextPath + "/";
@@ -120,4 +155,24 @@ public void configureMessageConverters(List<HttpMessageConverter<?>> converters)
     WebMVCConfig.log.info("Number of converters available after adding locals "
         + Integer.toString(converters.size()));
   }
+
+
+
+  static public Class<? extends ProductBusinessLogic> selectFormatterClass(String acceptHeaderValue)
+      throws AcceptFormatNotSupportedException {
+
+    String[] acceptOrderedValues = acceptHeaderValue.split(",", 0);
+
+    for (String acceptValue : acceptOrderedValues) {
+      if (WebMVCConfig.formatters.containsKey(acceptValue)) {
+        return WebMVCConfig.formatters.get(acceptValue);
+      }
+    }
+
+    // if none of the Accept format proposed matches
+    throw new AcceptFormatNotSupportedException(
+        "None of the format(s) " + acceptHeaderValue + "is supported.");
+
+  }
+
 }