Add iterable objects validation (halo-dev#970)

src/main/java/run/halo/app/utils/ValidationUtils.java

@@ -1,15 +1,14 @@
 package run.halo.app.utils;
 
+import org.hibernate.validator.internal.engine.path.PathImpl;
 import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
 import org.springframework.util.CollectionUtils;
 import org.springframework.validation.FieldError;
 
-import javax.validation.ConstraintViolation;
-import javax.validation.ConstraintViolationException;
-import javax.validation.Validation;
-import javax.validation.Validator;
+import javax.validation.*;
 import java.util.*;
+import java.util.concurrent.atomic.AtomicInteger;
 
 /**
  * Object validation utilities.
@@ -30,7 +29,7 @@ private ValidationUtils() {
      * @return validator
      */
     @NonNull
-    public static Validator getValidatorOrCreate() {
+    public static Validator getValidator() {
         if (VALIDATOR == null) {
             synchronized (ValidationUtils.class) {
                 if (VALIDATOR == null) {
@@ -52,17 +51,55 @@ public static Validator getValidatorOrCreate() {
      */
     public static void validate(Object obj, Class<?>... groups) {
 
-        Validator validator = getValidatorOrCreate();
+        Validator validator = getValidator();
 
-        // Validate the object
-        Set<ConstraintViolation<Object>> constraintViolations = validator.validate(obj, groups);
+        if (obj instanceof Iterable) {
+            // validate for iterable
+            validate((Iterable<?>) obj, groups);
+        } else {
+            // validate the non-iterable object
+            Set<ConstraintViolation<Object>> constraintViolations = validator.validate(obj, groups);
 
-        if (!CollectionUtils.isEmpty(constraintViolations)) {
-            // If contain some errors then throw constraint violation exception
-            throw new ConstraintViolationException(constraintViolations);
+            if (!CollectionUtils.isEmpty(constraintViolations)) {
+                // If contain some errors then throw constraint violation exception
+                throw new ConstraintViolationException(constraintViolations);
+            }
         }
     }
 
+    /**
+     * Validates iterable objects.
+     *
+     * @param objs   iterable objects could be null
+     * @param groups validation groups
+     */
+    public static void validate(@Nullable Iterable<?> objs, @Nullable Class<?>... groups) {
+        if (objs == null) {
+            return;
+        }
+
+        // get validator
+        Validator validator = getValidator();
+
+        // wrap index
+        AtomicInteger i = new AtomicInteger(0);
+        final Set<ConstraintViolation<?>> allViolations = new LinkedHashSet<>();
+        objs.forEach(obj -> {
+            int index = i.getAndIncrement();
+            Set<? extends ConstraintViolation<?>> violations = validator.validate(obj, groups);
+            violations.forEach(violation -> {
+                Path path = violation.getPropertyPath();
+                if (path instanceof PathImpl) {
+                    PathImpl pathImpl = (PathImpl) path;
+                    pathImpl.makeLeafNodeIterableAndSetIndex(index);
+                }
+                allViolations.add(violation);
+            });
+        });
+        if (!CollectionUtils.isEmpty(allViolations)) {
+            throw new ConstraintViolationException(allViolations);
+        }
+    }
 
     /**
      * 将字段验证错误转换为标准的map型，key:value = field:message

src/test/java/run/halo/app/utils/ValidationUtilsTest.java

@@ -0,0 +1,84 @@
+package run.halo.app.utils;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import org.junit.jupiter.api.Test;
+
+import javax.validation.ConstraintViolation;
+import javax.validation.ConstraintViolationException;
+import javax.validation.Validator;
+import javax.validation.constraints.NotBlank;
+import java.util.*;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+/**
+ * Validation utils test.
+ *
+ * @author johnniang
+ */
+class ValidationUtilsTest {
+
+    Validator validator = ValidationUtils.getValidator();
+
+    @Test
+    void validateObjectTest() {
+        Car car = new Car(null);
+        Set<ConstraintViolation<Car>> violations = validator.validate(car);
+        validateObjectAssert(violations);
+
+        ConstraintViolationException exception = assertThrows(ConstraintViolationException.class,
+            () -> ValidationUtils.validate(car));
+        validateObjectAssert(exception.getConstraintViolations());
+    }
+
+    void validateObjectAssert(Set<? extends ConstraintViolation<?>> violations) {
+        assertEquals(1, violations.size());
+        ConstraintViolation<?> violation = violations.iterator().next();
+        assertEquals("name", violation.getPropertyPath().toString());
+        assertEquals("Name must not be blank", violation.getMessage());
+    }
+
+    @Test
+    void validateListTest() {
+        List<Car> cars = Arrays.asList(new Car(""),
+            new Car("car name"),
+            new Car(null));
+
+        ConstraintViolationException exception = assertThrows(ConstraintViolationException.class,
+            () -> ValidationUtils.validate(cars));
+
+        validateIteratorTest(exception.getConstraintViolations());
+    }
+
+    void validateIteratorTest(Set<? extends ConstraintViolation<?>> violations) {
+        assertEquals(2, violations.size());
+
+        LinkedList<? extends ConstraintViolation<?>> violationList = new LinkedList<>(violations);
+        violationList.sort(Comparator.comparing(v -> v.getPropertyPath().toString()));
+
+        // get first violation
+        ConstraintViolation<?> firstViolation = violationList.get(0);
+        // get second violation
+        ConstraintViolation<?> secondViolation = violationList.get(1);
+
+        assertEquals("name[0]", firstViolation.getPropertyPath().toString());
+        assertEquals("name[2]", secondViolation.getPropertyPath().toString());
+    }
+
+    /**
+     * Car entity.
+     *
+     * @author johnniang
+     */
+    @Data
+    @AllArgsConstructor
+    static class Car {
+
+        @NotBlank(message = "Name must not be blank")
+        private String name;
+
+    }
+
+}