Setup CORS with a filter by default

Author: jameskleeh

grails-core/src/main/groovy/grails/config/Settings.groovy

@@ -214,5 +214,9 @@ interface Settings {
      * Whether to execute Bootstrap classes
      */
     String SETTING_SKIP_BOOTSTRAP = "grails.bootstrap.skip";
+    /**
+     * Whether to load cors configuration via a filter (true) or interceptor(false)
+     */
+    String SETTING_CORS_FILTER = "grails.cors.filter";
 
 }

grails-plugin-url-mappings/src/main/groovy/org/grails/plugins/web/mapping/UrlMappingsGrailsPlugin.groovy

@@ -21,6 +21,7 @@ import grails.util.Environment
 import grails.util.GrailsUtil
 import grails.web.CamelCaseUrlConverter
 import grails.web.HyphenatedUrlConverter
+import grails.web.mapping.cors.GrailsCorsFilter
 import groovy.transform.CompileDynamic
 import groovy.transform.CompileStatic
 import org.grails.core.artefact.UrlMappingsArtefactHandler
@@ -37,7 +38,9 @@ import org.grails.web.mapping.mvc.UrlMappingsInfoHandlerAdapter
 import org.grails.web.mapping.servlet.UrlMappingsErrorPageCustomizer
 import org.springframework.aop.framework.ProxyFactoryBean
 import org.springframework.aop.target.HotSwappableTargetSource
+import org.springframework.boot.web.servlet.FilterRegistrationBean
 import org.springframework.context.ApplicationContext
+import org.springframework.core.Ordered
 
 /**
  * Handles the configuration of URL mappings.
@@ -67,11 +70,20 @@ class UrlMappingsGrailsPlugin extends Plugin {
 
         "${grails.web.UrlConverter.BEAN_NAME}"('hyphenated' == urlConverterType ? HyphenatedUrlConverter : CamelCaseUrlConverter)
 
+        boolean corsFilterEnabled = config.getProperty(Settings.SETTING_CORS_FILTER, Boolean, true)
+
         grailsCorsConfiguration(GrailsCorsConfiguration)
 
         urlMappingsHandlerMapping(UrlMappingsHandlerMapping, ref("grailsUrlMappingsHolder")) {
-            grailsCorsConfiguration = ref("grailsCorsConfiguration")
+            if (!corsFilterEnabled) {
+                grailsCorsConfiguration = ref("grailsCorsConfiguration")
+            }
         }
+
+        if (corsFilterEnabled) {
+            grailsCorsFilter(GrailsCorsFilter, ref("grailsCorsConfiguration"))
+        }
+
         urlMappingsInfoHandlerAdapter(UrlMappingsInfoHandlerAdapter)
         urlMappingsErrorPageCustomizer(UrlMappingsErrorPageCustomizer)
         grailsLinkGenerator(cacheUrls ? CachingLinkGenerator : DefaultLinkGenerator, serverURL)

grails-web-url-mappings/src/main/groovy/grails/web/mapping/cors/GrailsCorsFilter.groovy

@@ -0,0 +1,29 @@
+package grails.web.mapping.cors
+
+import org.springframework.core.Ordered
+import org.springframework.web.cors.CorsConfiguration
+import org.springframework.web.cors.UrlBasedCorsConfigurationSource
+import org.springframework.web.filter.CorsFilter
+
+/**
+ * Created by jameskleeh on 10/20/16.
+ */
+class GrailsCorsFilter extends CorsFilter implements Ordered {
+
+    public GrailsCorsFilter(GrailsCorsConfiguration corsConfiguration) {
+        super(configurationSource(corsConfiguration.corsConfigurations))
+    }
+
+    private static UrlBasedCorsConfigurationSource configurationSource(Map<String, CorsConfiguration> corsConfigurations) {
+        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource()
+        corsConfigurations.each { String key, CorsConfiguration config ->
+            source.registerCorsConfiguration(key, config)
+        }
+        source
+    }
+
+    @Override
+    int getOrder() {
+        HIGHEST_PRECEDENCE
+    }
+}