Required oneof

tools/tool-base/src/main/java/io/spine/code/gen/java/OneofDeclaration.java → base/src/main/java/io/spine/code/proto/OneofDeclaration.java

@@ -18,22 +18,18 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-package io.spine.code.gen.java;
+package io.spine.code.proto;
 
-import com.google.common.collect.ImmutableSet;
+import com.google.errorprone.annotations.Immutable;
 import com.google.protobuf.Descriptors.OneofDescriptor;
-import io.spine.code.java.ClassName;
-import io.spine.code.java.SimpleClassName;
-import io.spine.code.proto.FieldName;
 import io.spine.type.MessageType;
 
 import static com.google.common.base.Preconditions.checkNotNull;
-import static com.google.common.collect.ImmutableSet.toImmutableSet;
-import static java.lang.String.format;
 
 /**
- * A declaration of a {@code oneof} field.
+ * A declaration of a {@code oneof} field group.
  */
+@Immutable
 public final class OneofDeclaration {
 
     private final OneofDescriptor oneof;
@@ -44,17 +40,6 @@ public OneofDeclaration(OneofDescriptor oneof, MessageType type) {
         this.declaringType = checkNotNull(type);
     }
 
-    public static ImmutableSet<OneofDeclaration> allFromType(MessageType declaringType) {
-        checkNotNull(declaringType);
-        ImmutableSet<OneofDeclaration> result =
-                declaringType.descriptor()
-                             .getOneofs()
-                             .stream()
-                             .map(oneof -> new OneofDeclaration(oneof, declaringType))
-                             .collect(toImmutableSet());
-        return result;
-    }
-
     /**
      * Obtains the name of the {@code oneof} field.
      */
@@ -63,21 +48,16 @@ public FieldName name() {
     }
 
     /**
-     * Obtains the name of an enum which represents cases of the {@code oneof} field.
-     *
-     * <p>Such an enum should be nested in the declaring message class.
-     *
-     * <p>If the declaring message class name is {@code com.acme.cms.Customer} and the {@code oneof}
-     * name is {@code auth_provider}, the resulting class name would be
-     * {@code com.acme.cms.Customer$AuthProviderCase}.
-     *
-     * @return the case enum FQN
+     * Obtains the {@code oneof} descriptor.
+     */
+    public OneofDescriptor descriptor() {
+        return oneof;
+    }
+
+    /**
+     * Obtains the type containing this group.
      */
-    public ClassName javaCaseEnum() {
-        ClassName declaringClassName = declaringType.javaClassName();
-        io.spine.code.gen.java.FieldName oneofName =
-                io.spine.code.gen.java.FieldName.from(name());
-        SimpleClassName enumName = SimpleClassName.create(format("%sCase", oneofName.capitalize()));
-        return declaringClassName.withNested(enumName);
+    public MessageType declaringType() {
+        return declaringType;
     }
 }

base/src/main/java/io/spine/validate/ConstraintTranslator.java

@@ -22,6 +22,7 @@
 
 import io.spine.validate.option.DistinctConstraint;
 import io.spine.validate.option.GoesConstraint;
+import io.spine.validate.option.IsRequiredConstraint;
 import io.spine.validate.option.PatternConstraint;
 import io.spine.validate.option.RangedConstraint;
 import io.spine.validate.option.RequiredConstraint;
@@ -101,6 +102,14 @@ public interface ConstraintTranslator<T> {
      */
     void visitRequiredField(RequiredFieldConstraint constraint);
 
+    /**
+     * Translates the given {@link IsRequiredConstraint}.
+     *
+     * @param constraint
+     *         the constraint of a oneof group
+     */
+    void visitRequiredOneof(IsRequiredConstraint constraint);
+
     /**
      * Translates the given {@link CustomConstraint}.
      *

base/src/main/java/io/spine/validate/Constraints.java

@@ -23,7 +23,9 @@
 import com.google.common.collect.ImmutableList;
 import com.google.errorprone.annotations.Immutable;
 import io.spine.code.proto.FieldContext;
+import io.spine.code.proto.OneofDeclaration;
 import io.spine.type.MessageType;
+import io.spine.validate.option.IsRequired;
 import io.spine.validate.option.RequiredField;
 
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -77,6 +79,7 @@ static Constraints loadFor(MessageType type, FieldContext context) {
             .flatMap(FieldConstraints::of)
             .forEach(constraintBuilder::add);
         addRequiredField(type, constraintBuilder);
+        scanIsRequired(type, constraintBuilder);
         return new Constraints(constraintBuilder.build());
     }
 
@@ -89,6 +92,18 @@ private static void addRequiredField(MessageType type,
         }
     }
 
+    private static void scanIsRequired(MessageType type,
+                                       ImmutableList.Builder<Constraint> builder) {
+        IsRequired option = new IsRequired();
+        type.descriptor()
+            .getOneofs()
+            .stream()
+            .filter(option::valuePresent)
+            .map(descriptor -> new OneofDeclaration(descriptor, type))
+            .map(option::constraintFor)
+            .forEach(builder::add);
+    }
+
     /**
      * Assembles non-standard constraints from the given message type in the given field context.
      */

base/src/main/java/io/spine/validate/MessageValidator.java

@@ -24,6 +24,7 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Range;
 import com.google.protobuf.Message;
+import io.spine.base.Field;
 import io.spine.base.FieldPath;
 import io.spine.code.proto.FieldContext;
 import io.spine.code.proto.FieldDeclaration;
@@ -32,6 +33,7 @@
 import io.spine.type.TypeName;
 import io.spine.validate.option.DistinctConstraint;
 import io.spine.validate.option.GoesConstraint;
+import io.spine.validate.option.IsRequiredConstraint;
 import io.spine.validate.option.PatternConstraint;
 import io.spine.validate.option.RangedConstraint;
 import io.spine.validate.option.RequiredConstraint;
@@ -190,6 +192,22 @@ public void visitRequiredField(RequiredFieldConstraint constraint) {
         violation.ifPresent(violations::add);
     }
 
+    @Override
+    public void visitRequiredOneof(IsRequiredConstraint constraint) {
+        Optional<FieldValue> fieldValue = message.valueOf(constraint.declaration());
+        boolean noneSet = !fieldValue.isPresent();
+        if (noneSet) {
+            MessageType targetType = constraint.targetType();
+            ConstraintViolation violation = ConstraintViolation
+                    .newBuilder()
+                    .setMsgFormat(constraint.errorMessage(message.context()))
+                    .setFieldPath(Field.named(constraint.oneofName().value()).path())
+                    .setTypeName(targetType.name().value())
+                    .build();
+            violations.add(violation);
+        }
+    }
+
     @Override
     public void visitCustom(CustomConstraint constraint) {
         ImmutableList<ConstraintViolation> violations = constraint.validate(message);

base/src/main/java/io/spine/validate/MessageValue.java

@@ -27,6 +27,7 @@
 import com.google.protobuf.Message;
 import io.spine.code.proto.FieldContext;
 import io.spine.code.proto.FieldDeclaration;
+import io.spine.code.proto.OneofDeclaration;
 import io.spine.type.MessageType;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -147,10 +148,10 @@ public FieldValue valueOf(FieldDeclaration field) {
     }
 
     /**
-     * Obtains the value of a populated {@code Oneof} field.
+     * Obtains the value of a populated {@code oneof} field.
      *
      * @param oneof
-     *         the {@code Oneof} descriptor
+     *         the {@code oneof} descriptor
      * @return a value of the populated field
      *         or {@code Optional.empty()} if the field was not populated
      * @throws IllegalArgumentException
@@ -163,6 +164,20 @@ public Optional<FieldValue> valueOf(OneofDescriptor oneof) {
         return valueOfNullable(field);
     }
 
+    /**
+     * Obtains the value of a populated {@code oneof} field.
+     *
+     * @param oneof
+     *         the {@code oneof} declaration
+     * @return a value of the populated field
+     *         or {@code Optional.empty()} if the field was not populated
+     * @throws IllegalArgumentException
+     *         if the if the message doesn't declare this oneof
+     */
+    public Optional<FieldValue> valueOf(OneofDeclaration oneof) {
+        return valueOf(oneof.descriptor());
+    }
+
     /** Returns the context of the message. */
     @SuppressWarnings("unused")
     FieldContext context() {
@@ -188,5 +203,4 @@ private FieldValue valueOfField(FieldDescriptor field) {
     private Object readValue(FieldDescriptor field) {
         return asFieldAware == null ? message.getField(field) : asFieldAware.readValue(field);
     }
-
 }

base/src/test/java/io/spine/validate/builders/package-info.java → base/src/main/java/io/spine/validate/option/IsRequired.java

@@ -18,14 +18,34 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+package io.spine.validate.option;
+
+import com.google.errorprone.annotations.Immutable;
+import com.google.protobuf.Descriptors.OneofDescriptor;
+import io.spine.code.proto.OneofDeclaration;
+import io.spine.validate.Constraint;
+
+import java.util.Optional;
+
+import static io.spine.option.OptionsProto.isRequired;
+
 /**
- * Tests of validating builders are placed into this package
- * to simulate usage of the public API.
+ * A {@code oneof} validation option which constrains the target {@code oneof} group to be set.
+ *
+ * <p>If the value of the option is {@code true}, one of the fields in the group must be set.
  */
-@CheckReturnValue
-@ParametersAreNonnullByDefault
-package io.spine.validate.builders;
+@Immutable
+public class IsRequired implements ValidatingOption<Boolean, OneofDeclaration, OneofDescriptor> {
 
-import com.google.errorprone.annotations.CheckReturnValue;
+    @Override
+    public Constraint constraintFor(OneofDeclaration field) {
+        return new IsRequiredConstraint(field);
+    }
 
-import javax.annotation.ParametersAreNonnullByDefault;
+    @Override
+    public Optional<Boolean> valueFrom(OneofDescriptor descriptor) {
+        boolean value = descriptor.getOptions()
+                                  .getExtension(isRequired);
+        return value ? Optional.of(true) : Optional.empty();
+    }
+}

base/src/main/java/io/spine/validate/option/IsRequiredConstraint.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright 2020, TeamDev. All rights reserved.
+ *
+ * Redistribution and use in source and/or binary forms, with or without
+ * modification, must retain the above copyright notice and the following
+ * disclaimer.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package io.spine.validate.option;
+
+import com.google.errorprone.annotations.Immutable;
+import io.spine.code.proto.FieldContext;
+import io.spine.code.proto.FieldName;
+import io.spine.code.proto.OneofDeclaration;
+import io.spine.type.MessageType;
+import io.spine.validate.Constraint;
+import io.spine.validate.ConstraintTranslator;
+
+/**
+ * A {@code oneof} group constraint which signifies that one of the fields must be set.
+ */
+@Immutable
+public final class IsRequiredConstraint implements Constraint {
+
+    private final OneofDeclaration declaration;
+
+    IsRequiredConstraint(OneofDeclaration declaration) {
+        this.declaration = declaration;
+    }
+
+    @Override
+    public MessageType targetType() {
+        return declaration.declaringType();
+    }
+
+    @Override
+    public String errorMessage(FieldContext field) {
+        return String.format("One of fields in group `%s` must be set.", declaration.name());
+    }
+
+    @Override
+    public void accept(ConstraintTranslator<?> visitor) {
+        visitor.visitRequiredOneof(this);
+    }
+
+    /**
+     * Obtains the name of the {@code oneof} group.
+     */
+    public FieldName oneofName() {
+        return declaration.name();
+    }
+
+    /**
+     * Obtains the {@code oneof} declaration.
+     */
+    public OneofDeclaration declaration() {
+        return declaration;
+    }
+}