Add a UUID Value Converter

grails-databinding/src/main/groovy/org/grails/databinding/converters/UUIDConverter.groovy

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2018 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 org.grails.databinding.converters
+
+import grails.databinding.converters.ValueConverter;
+import groovy.transform.CompileStatic
+
+@CompileStatic
+class UUIDConverter implements ValueConverter {
+
+    @Override
+    boolean canConvert(value) {
+        value instanceof String
+    }
+
+    @Override
+    def convert(value) {
+        if(value) {
+            try {
+                return UUID.fromString(value as String)
+            } catch(IllegalArgumentException ignore) {
+                return null
+            }
+        }
+        return null
+    }
+
+    @Override
+    Class<?> getTargetType() {
+        UUID
+    }
+}

grails-databinding/src/test/groovy/org/grails/databinding/converters/UUIDConversionSpec.groovy

@@ -0,0 +1,66 @@
+package org.grails.databinding.converters
+
+
+import grails.databinding.SimpleMapDataBindingSource
+
+import grails.databinding.SimpleDataBinder
+
+import spock.lang.Specification
+
+class UUIDConversionSpec extends Specification {
+
+    void 'Binding String to a UUID'() {
+        given:
+        def binder = new SimpleDataBinder()
+        binder.registerConverter new UUIDConverter()
+        def testClass = new UUIDTestClass()
+
+        and:
+        def givenUUID = '534f7cee-bf88-45f3-96f2-9cae0828cd16'
+
+        when:
+        binder.bind testClass, [uuid: givenUUID] as SimpleMapDataBindingSource
+
+        then:
+        testClass.uuid instanceof UUID
+        testClass.uuid.toString() == givenUUID
+    }
+
+    void 'Binding badly formatted string to a UUID'() {
+        given:
+        def binder = new SimpleDataBinder()
+        binder.registerConverter new UUIDConverter()
+        def testClass = new UUIDTestClass()
+
+        and:
+        def givenUUID = '123-not-a-uuid-3291'
+
+        when:
+        binder.bind testClass, [uuid: givenUUID] as SimpleMapDataBindingSource
+
+        then:
+        notThrown(IllegalArgumentException)
+        testClass.uuid == null
+    }
+
+    void 'Binding null to UUID'() {
+        given:
+        def binder = new SimpleDataBinder()
+        binder.registerConverter new UUIDConverter()
+        def testClass = new UUIDTestClass()
+
+        and:
+        def givenUUID = null
+
+        when:
+        binder.bind testClass, [uuid: givenUUID] as SimpleMapDataBindingSource
+
+        then:
+        notThrown(IllegalArgumentException)
+        testClass.uuid == null
+    }
+}
+
+class UUIDTestClass {
+    UUID uuid
+}

grails-plugin-databinding/src/main/groovy/org/grails/plugins/databinding/DataBindingGrailsPlugin.groovy

@@ -20,6 +20,7 @@ import grails.plugins.Plugin
 import grails.util.GrailsUtil
 import grails.web.databinding.DataBindingUtils
 import grails.web.databinding.GrailsWebDataBinder
+import org.grails.databinding.converters.UUIDConverter
 import org.grails.web.databinding.bindingsource.DataBindingSourceRegistry
 import org.grails.web.databinding.bindingsource.DefaultDataBindingSourceRegistry
 import org.grails.web.databinding.bindingsource.HalJsonDataBindingSourceCreator
@@ -69,6 +70,7 @@ class DataBindingGrailsPlugin extends Plugin {
         }
 
         timeZoneConverter(TimeZoneConverter)
+        uuidConverter(UUIDConverter)
 
         defaultDateConverter(DateConversionHelper) {
             formatStrings = dateFormats