feat: Add enctype to Form

test-suite-thymeleaf-fieldset/src/test/resources/views/fieldset/form.html

@@ -1 +1 @@
-<form th:fragment="form(form)" xmlns:th="http://www.thymeleaf.org" th:action="${form.action()}" th:method="${form.method()}"><fieldset th:replace="~{fieldset/fieldset :: fieldset(${form.fieldset()})}"></fieldset></form>
+<th:block th:fragment="form(form)" xmlns:th="http://www.thymeleaf.org"><form th:action="${form.action()}" th:method="${form.method()}" th:enctype="${form.enctype()}"><fieldset th:replace="~{fieldset/fieldset :: fieldset(${form.fieldset()})}"></fieldset></form></th:block>

views-fieldset-tck/src/main/java/io/micronaut/views/fields/tck/FormEncTypeRenderTest.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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 io.micronaut.views.fields.tck;
+
+import io.micronaut.test.extensions.junit5.annotation.MicronautTest;
+import io.micronaut.views.ViewsRenderer;
+import io.micronaut.views.fields.Fieldset;
+import io.micronaut.views.fields.Form;
+import org.junit.jupiter.api.Test;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Map;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+
+@SuppressWarnings({"java:S5960"}) // Assertions are fine, these are tests
+@MicronautTest(startApplication = false)
+class FormEncTypeRenderTest {
+
+    @Test
+    void render(ViewsRenderer<Map<String, Object>, ?> viewsRenderer) throws IOException {
+        assertNotNull(viewsRenderer);
+        Form form = new Form("/foo/bar", "post", new Fieldset(Collections.emptyList(), Collections.emptyList()), "application/x-www-form-urlencoded");
+        assertEquals("""
+                <form action="/foo/bar" method="post" enctype="application/x-www-form-urlencoded">\
+                </form>""",
+                TestUtils.render("fieldset/form.html", viewsRenderer, Map.of("form", form)));
+    }
+}

views-fieldset/src/main/java/io/micronaut/views/fields/Fieldset.java

@@ -20,6 +20,8 @@
 import io.micronaut.core.annotation.NonNull;
 import io.micronaut.core.util.CollectionUtils;
 import io.micronaut.views.fields.messages.Message;
+import jakarta.validation.Valid;
+import jakarta.validation.constraints.NotEmpty;
 
 import java.util.List;
 
@@ -34,8 +36,8 @@
  */
 @Experimental
 @Introspected
-public record Fieldset(@NonNull List<? extends FormElement> fields,
-                       @NonNull List<Message> errors) {
+public record Fieldset(@NonNull @NotEmpty List<@Valid ? extends FormElement> fields,
+                       @NonNull List<@Valid Message> errors) {
 
     /**
      *

views-fieldset/src/main/java/io/micronaut/views/fields/Form.java

@@ -15,18 +15,63 @@
  */
 package io.micronaut.views.fields;
 
-import io.micronaut.core.annotation.Experimental;
-import io.micronaut.core.annotation.Introspected;
+import io.micronaut.core.annotation.*;
+import io.micronaut.views.fields.constraints.EnctypePostRequired;
+import jakarta.validation.Valid;
+import jakarta.validation.constraints.NotBlank;
+import jakarta.validation.constraints.NotNull;
+import jakarta.validation.constraints.Pattern;
 
 /**
  * Representation of an HTML form.
  * @author Sergio del Amo
  * @since 4.1.0
  * @param action Form Action
- * @param method Form Method. For example `post`
+ * @param method Form Method. either `get` or `post`
  * @param fieldset Form fields
+ * @param enctype how the form-data should be encoded when submitting it to the server
  */
 @Experimental
+@EnctypePostRequired
 @Introspected
-public record Form(String action, String method, Fieldset fieldset) {
+public record Form(@NonNull @NotBlank String action,
+                   @NonNull @NotBlank @Pattern(regexp = "get|post") String method,
+                   @NonNull @NotNull @Valid Fieldset fieldset,
+                   @Nullable @Pattern(regexp = "application/x-www-form-urlencoded|multipart/form-data|text/plain") String enctype) {
+
+    private static final String POST = "post";
+
+    /**
+     *
+     * @param action Form Action
+     * @param method Form Method. either `get` or `post`
+     * @param fieldset Form fields
+     */
+    public Form(@NonNull String action,
+                @NonNull String method,
+                @NonNull Fieldset fieldset) {
+        this(action, method, fieldset, null);
+    }
+
+    /**
+     *
+     * @param action Form Action
+     * @param fieldset Form fields
+     */
+    public Form(@NonNull String action,
+                @NonNull Fieldset fieldset) {
+        this(action, POST, fieldset, null);
+    }
+
+    /**
+     *
+     * @param action Form Action
+     * @param fieldset Form fields
+     * @param enctype how the form-data should be encoded when submitting it to the server
+     */
+    public Form(@NonNull String action,
+                @NonNull Fieldset fieldset,
+                @Nullable String enctype) {
+        this(action, POST, fieldset, enctype);
+    }
 }

views-fieldset/src/main/java/io/micronaut/views/fields/constraints/EnctypePostRequired.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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 io.micronaut.views.fields.constraints;
+
+import jakarta.validation.Constraint;
+import jakarta.validation.Payload;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * The annotated {@link io.micronaut.views.fields.Form} must not have an encytpe declared if the method is not post.
+ * @author Sergio del Amo
+ * @since 5.1.0
+ *
+ */
+@Constraint(validatedBy = EnctypePostRequiredValidator.class)
+@Target({ElementType.TYPE, ElementType.FIELD})
+@Retention(RetentionPolicy.RUNTIME)
+public @interface EnctypePostRequired {
+    String MESSAGE = "io.micronaut.views.fields.constraints.EnctypePostRequired.message";
+
+    String message() default "{" + MESSAGE + "}";
+
+    Class<?>[] groups() default {};
+
+    Class<? extends Payload>[] payload() default {};
+}

views-fieldset/src/main/java/io/micronaut/views/fields/constraints/EnctypePostRequiredValidator.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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 io.micronaut.views.fields.constraints;
+
+import io.micronaut.core.annotation.AnnotationValue;
+import io.micronaut.core.annotation.Introspected;
+import io.micronaut.core.annotation.NonNull;
+import io.micronaut.core.annotation.Nullable;
+import io.micronaut.validation.validator.constraints.ConstraintValidator;
+import io.micronaut.validation.validator.constraints.ConstraintValidatorContext;
+import io.micronaut.views.fields.Form;
+
+/**
+ * Validator for the constraint {@link EnctypePostRequired} being applied to a {@link Form}.
+ * @author Sergio del Amo
+ * @since 5.1.0
+ */
+@Introspected
+public class EnctypePostRequiredValidator implements ConstraintValidator<EnctypePostRequired, Form> {
+
+    private static final String METHOD_POST = "post";
+
+    @Override
+    public boolean isValid(@Nullable Form form,
+                           @NonNull AnnotationValue<EnctypePostRequired> annotationMetadata,
+                           @NonNull ConstraintValidatorContext context) {
+        if (form == null) {
+            return true;
+        }
+        return form.enctype() == null || form.method().equals(METHOD_POST);
+    }
+}

views-fieldset/src/main/java/io/micronaut/views/fields/constraints/FormMessages.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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 io.micronaut.views.fields.constraints;
+
+import io.micronaut.context.StaticMessageSource;
+import io.micronaut.core.annotation.Internal;
+import jakarta.inject.Singleton;
+
+/**
+ * Messages contributed by Form validation annotations.
+ * @author Sergio del Amo
+ * @since 5.1.0
+ */
+@Singleton
+@Internal
+class FormMessages extends StaticMessageSource {
+    private static final String ENCTYPE_POST_REQUIRED_MESSAGE = "enctype attribute can be used only if method equals post";
+
+    private static final String MESSAGE_SUFFIX = ".message";
+
+    FormMessages() {
+        addMessage(EnctypePostRequired.class.getName() + MESSAGE_SUFFIX, ENCTYPE_POST_REQUIRED_MESSAGE);
+    }
+}

views-fieldset/src/main/java/io/micronaut/views/fields/constraints/package-info.java

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2017-2023 original 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
+ *
+ * https://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.
+ */
+/**
+ * Custom Constraints for validating HTML Forms.
+ * @author Sergio del Amo
+ * @since 5.1.0
+ */
+package io.micronaut.views.fields.constraints;

views-fieldset/src/main/java/io/micronaut/views/fields/messages/Message.java

@@ -16,11 +16,13 @@
 package io.micronaut.views.fields.messages;
 
 import io.micronaut.core.annotation.Experimental;
+import io.micronaut.core.annotation.Introspected;
 import io.micronaut.core.annotation.NonNull;
 import io.micronaut.core.annotation.Nullable;
 import io.micronaut.core.beans.BeanProperty;
 import io.micronaut.core.util.StringUtils;
 import jakarta.validation.ConstraintViolation;
+import jakarta.validation.constraints.NotBlank;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -33,7 +35,9 @@
  * @param code The i18n code which can be used to fetch a localized message.
  */
 @Experimental
-public record Message(@NonNull String defaultMessage, @Nullable String code) implements Comparable<Message> {
+@Introspected
+public record Message(@NonNull @NotBlank String defaultMessage,
+                      @Nullable String code) implements Comparable<Message> {
     private static final String REGEX = "(.)([A-Z])";
     private static final String REPLACEMENT = "$1 $2";
     private static final String DOT = ".";

views-fieldset/src/test/java/io/micronaut/views/fields/FormTest.java

@@ -1,14 +1,60 @@
 package io.micronaut.views.fields;
 
 import io.micronaut.core.beans.BeanIntrospection;
+import io.micronaut.test.extensions.junit5.annotation.MicronautTest;
+import io.micronaut.validation.validator.Validator;
+import io.micronaut.views.fields.elements.InputSubmitFormElement;
+import jakarta.validation.ConstraintViolation;
 import org.junit.jupiter.api.Test;
 
+import java.util.Collections;
+import java.util.Set;
+
 import static org.junit.jupiter.api.Assertions.*;
 
+@MicronautTest(startApplication = false)
 class FormTest {
     @Test
     void isAnnotatedWithIntrospected() {
         assertDoesNotThrow(() -> BeanIntrospection.getIntrospection(Form.class));
     }
 
+    @Test
+    void formValidation(Validator validator) {
+        Fieldset fieldset = new Fieldset(Collections.singletonList(new InputSubmitFormElement(FormGenerator.SUBMIT)), Collections.emptyList());
+        // action cannot be an empty string
+        assertFalse(validator.validate(new Form("", "post", fieldset, "application/x-www-form-urlencoded")).isEmpty());
+        // action cannot be null
+        assertFalse(validator.validate(new Form(null, "post", fieldset, "application/x-www-form-urlencoded")).isEmpty());
+
+        // method cannot be an empty string
+        assertFalse(validator.validate(new Form("/foo/bar", "", fieldset, null)).isEmpty());
+        // method cannot be null
+        assertFalse(validator.validate(new Form("/foo/bar", null, fieldset, null)).isEmpty());
+        // method can only be get or post
+        assertFalse(validator.validate(new Form("/foo/bar", "put", fieldset, null)).isEmpty());
+
+        //method cannot be get if enctype
+        Set<ConstraintViolation<Form>> violations = validator.validate(new Form("/foo/bar", "get", fieldset, "application/x-www-form-urlencoded"));
+        assertFalse(violations.isEmpty());
+        assertEquals(Collections.singletonList("enctype attribute can be used only if method equals post"), violations.stream().map(ConstraintViolation::getMessage).toList());
+
+        // fieldset cannot be null
+        Fieldset invalidFieldset = new Fieldset(Collections.emptyList(), Collections.emptyList());
+        assertFalse(validator.validate(new Form("/foo/bar", "post", invalidFieldset, "application/x-www-form-urlencoded")).isEmpty());
+
+        // fieldset must be valid
+        assertFalse(validator.validate(new Form("/foo/bar", "post", null, "application/x-www-form-urlencoded")).isEmpty());
+
+        // enctype has to be form-url-enconded form-data or txt
+        assertFalse(validator.validate(new Form("/foo/bar", "post", fieldset, "text/html")).isEmpty());
+
+        // enctype can be null
+        assertTrue(validator.validate(new Form("/foo/bar", "post", fieldset, null)).isEmpty());
+        assertTrue(validator.validate(new Form("/foo/bar", "post", fieldset, "application/x-www-form-urlencoded")).isEmpty());
+        assertTrue(validator.validate(new Form("/foo/bar", "post", fieldset, "multipart/form-data")).isEmpty());
+        assertTrue(validator.validate(new Form("/foo/bar", "post", fieldset, "text/plain")).isEmpty());
+        assertTrue(validator.validate(new Form("/foo/bar", "get", fieldset, null)).isEmpty());
+
+    }
 }

views-fieldset/src/test/java/io/micronaut/views/fields/messages/MessageTest.java

@@ -0,0 +1,20 @@
+package io.micronaut.views.fields.messages;
+
+import io.micronaut.test.extensions.junit5.annotation.MicronautTest;
+import io.micronaut.validation.validator.Validator;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@MicronautTest(startApplication = false)
+class MessageTest {
+
+    @Test
+    void messageValidation(Validator validator) {
+        assertTrue(validator.validate(Message.of("Foo")).isEmpty());
+        assertTrue(validator.validate(Message.of("Foo", "foo.code")).isEmpty());
+        assertFalse(validator.validate(Message.of("")).isEmpty());
+        String msg = null;
+        assertFalse(validator.validate(Message.of(msg)).isEmpty());
+    }
+}