Add json enricher and json field filter

scm-core/src/main/java/sonia/scm/web/JsonEnricher.java

@@ -0,0 +1,10 @@
+package sonia.scm.web;
+
+import sonia.scm.plugin.ExtensionPoint;
+
+@ExtensionPoint
+public interface JsonEnricher {
+
+  void enrich(JsonEnricherContext context);
+
+}

scm-core/src/main/java/sonia/scm/web/JsonEnricherContext.java

@@ -0,0 +1,31 @@
+package sonia.scm.web;
+
+import com.fasterxml.jackson.databind.JsonNode;
+
+import javax.ws.rs.core.MediaType;
+import java.net.URI;
+
+public class JsonEnricherContext {
+
+  private URI requestUri;
+  private MediaType responseMediaType;
+  private JsonNode responseEntity;
+
+  public JsonEnricherContext(URI requestUri, MediaType responseMediaType, JsonNode responseEntity) {
+    this.requestUri = requestUri;
+    this.responseMediaType = responseMediaType;
+    this.responseEntity = responseEntity;
+  }
+
+  public URI getRequestUri() {
+    return requestUri;
+  }
+
+  public MediaType getResponseMediaType() {
+    return responseMediaType;
+  }
+
+  public JsonNode getResponseEntity() {
+    return responseEntity;
+  }
+}

scm-core/src/main/java/sonia/scm/web/VndMediaType.java

@@ -0,0 +1,28 @@
+package sonia.scm.web;
+
+import javax.ws.rs.core.MediaType;
+
+public class VndMediaType {
+  private static final String VERSION = "2";
+  private static final String TYPE = "application";
+  private static final String SUBTYPE_PREFIX = "vnd.scmm-";
+  private static final String PREFIX = TYPE + "/" + SUBTYPE_PREFIX;
+  private static final String SUFFIX = "+json;v=" + VERSION;
+
+  public static final String USER = PREFIX + "user" + SUFFIX;
+
+  private VndMediaType() {
+  }
+
+  public static MediaType jsonType(String resource) {
+    return MediaType.valueOf(json(resource));
+  }
+
+  public static String json(String resource) {
+    return PREFIX + resource + SUFFIX;// ".v2+json";
+  }
+
+  public static boolean isVndType(MediaType type) {
+    return type.getType().equals(TYPE) && type.getSubtype().startsWith(SUBTYPE_PREFIX);
+  }
+}