[SHIBUI-996]

Added exception handler for database constraint exception.
Added i18n error message.

backend/src/main/java/edu/internet2/tier/shibboleth/admin/ui/controller/support/RestControllersSupport.java

@@ -1,14 +1,17 @@
 package edu.internet2.tier.shibboleth.admin.ui.controller.support;
 
 import com.google.common.collect.ImmutableMap;
+import edu.internet2.tier.shibboleth.admin.ui.controller.ErrorResponse;
 import edu.internet2.tier.shibboleth.admin.ui.domain.resolvers.MetadataResolver;
 import edu.internet2.tier.shibboleth.admin.ui.repository.MetadataResolverRepository;
+import org.hibernate.exception.ConstraintViolationException;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
 import org.springframework.web.client.HttpClientErrorException;
 
+import static org.springframework.http.HttpStatus.BAD_REQUEST;
 import static org.springframework.http.HttpStatus.NOT_FOUND;
 
 /**
@@ -38,4 +41,9 @@ public ResponseEntity<?> notFoundHandler(HttpClientErrorException ex) {
         }
         throw ex;
     }
+
+    @ExceptionHandler(ConstraintViolationException.class)
+    public ResponseEntity<ErrorResponse> handleDatabaseConstraintViolation(ConstraintViolationException ex) {
+        return ResponseEntity.status(BAD_REQUEST).body(new ErrorResponse("400", "message.database-constraint"));
+    }
 }

backend/src/main/resources/i18n/messages.properties

@@ -397,6 +397,7 @@ message.wizard-status=Step { index } of { length }
 message.entity-id-min-unique=You must add at least one entity id target and they must each be unique.
 message.required-for-scripts=Required for Scripts
 message.required-for-regex=Required for Regex
+message.database-constraint=There was a database constraint problem processing the request. Check the request to insure that fields that must be unique are truly unique.
 
 tooltip.entity-id=Entity ID
 tooltip.service-provider-name=Service Provider Name (Dashboard Display Only)

backend/src/main/resources/i18n/messages_en.properties

@@ -398,6 +398,7 @@ message.wizard-status=Step { index } of { length }
 message.entity-id-min-unique=You must add at least one entity id target and they must each be unique.
 message.required-for-scripts=Required for Scripts
 message.required-for-regex=Required for Regex
+message.database-constraint=There was a database constraint problem processing the request. Check the request to insure that fields that must be unique are truly unique.
 
 tooltip.entity-id=Entity ID
 tooltip.service-provider-name=Service Provider Name (Dashboard Display Only)