CC-3635 - Add config to specify location of static resources

core/src/main/java/io/confluent/kafka/schemaregistry/rest/SchemaRegistryConfig.java

@@ -154,6 +154,8 @@ public class SchemaRegistryConfig extends RestConfig {
       "schema.registry.resource.extension.class";
   public static final String RESOURCE_EXTENSION_CONFIG =
       "resource.extension.class";
+  public static final String RESOURCE_STATIC_LOCATIONS_CONFIG =
+      "resource.static.locations";
   @Deprecated
   public static final String SCHEMAREGISTRY_INTER_INSTANCE_PROTOCOL_CONFIG =
       "schema.registry.inter.instance.protocol";
@@ -293,6 +295,9 @@ public class SchemaRegistryConfig extends RestConfig {
       + " like filters to Schema Registry. Typically used to add custom capability like logging, "
       + " security, etc. The schema.registry.resource.extension.class name is deprecated; "
       + "prefer using resource.extension.class instead.";
+  protected static final String RESOURCE_STATIC_LOCATIONS_DOC =
+      "  A list of classpath resources containing static resources to serve using the default "
+          + "servlet.";
   protected static final String SCHEMAREGISTRY_INTER_INSTANCE_PROTOCOL_DOC =
       "The protocol used while making calls between the instances of schema registry. The slave "
       + "to master node calls for writes and deletes will use the specified protocol. The default "
@@ -485,6 +490,9 @@ public static ConfigDef baseSchemaRegistryConfigDef() {
         .define(RESOURCE_EXTENSION_CONFIG, ConfigDef.Type.LIST, "",
                 ConfigDef.Importance.LOW, SCHEMAREGISTRY_RESOURCE_EXTENSION_DOC
         )
+        .define(RESOURCE_STATIC_LOCATIONS_CONFIG, ConfigDef.Type.LIST, "",
+            ConfigDef.Importance.LOW, RESOURCE_STATIC_LOCATIONS_DOC
+        )
         .define(SCHEMAREGISTRY_INTER_INSTANCE_PROTOCOL_CONFIG, ConfigDef.Type.STRING, "",
                 ConfigDef.Importance.LOW, SCHEMAREGISTRY_INTER_INSTANCE_PROTOCOL_DOC)
         .define(INTER_INSTANCE_PROTOCOL_CONFIG, ConfigDef.Type.STRING, HTTP,
@@ -651,6 +659,10 @@ public String definedResourceExtensionConfigName() {
     return RESOURCE_EXTENSION_CONFIG;
   }
 
+  public List<String> getStaticLocations() {
+    return getList(RESOURCE_STATIC_LOCATIONS_CONFIG);
+  }
+
   /**
    * Gets the inter.instance.protocol setting, handling the deprecated
    * schema.registry.inter.instance.protocol setting.

core/src/main/java/io/confluent/kafka/schemaregistry/rest/SchemaRegistryRestApplication.java

@@ -14,6 +14,8 @@
 
 package io.confluent.kafka.schemaregistry.rest;
 
+import org.eclipse.jetty.util.resource.Resource;
+import org.eclipse.jetty.util.resource.ResourceCollection;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -95,6 +97,19 @@ public void setupResources(Configurable<?> config, SchemaRegistryConfig schemaRe
     }
   }
 
+  @Override
+  protected ResourceCollection getStaticResources() {
+    List<String> locations = config.getStaticLocations();
+    if (locations != null && !locations.isEmpty()) {
+      Resource[] resources = config.getStaticLocations().stream()
+          .map(Resource::newClassPathResource)
+          .toArray(Resource[]::new);
+      return new ResourceCollection(resources);
+    } else {
+      return null;
+    }
+  }
+
   @Override
   public void onShutdown() {