#23 - Fix OpenAPI (swagger) gen for @NotNull (javax and Kotlin) @SiZe and @Email

Author: rbygrave

src/main/java/io/dinject/javalin/generator/openapi/KnownTypes.java

@@ -40,10 +40,15 @@ interface KnownType {
 
   KnownTypes() {
     add(new StringType(), String.class, char[].class, CharSequence.class);
-    add(new BoolType(), boolean.class, Boolean.class);
-    add(new IntegerType(), int.class, Integer.class);
-    add(new LongType(), long.class, Long.class);
-    add(new NumberType(), double.class, Double.class, float.class, Float.class, BigDecimal.class, BigInteger.class);
+    add(new BoolType(), boolean.class);
+    add(new BooleanType(), Boolean.class);
+    add(new IntType(), int.class);
+    add(new IntegerType(), Integer.class);
+    add(new PLongType(), long.class);
+    add(new LongType(), Long.class);
+
+    add(new PNumberType(), double.class, float.class);
+    add(new NumberType(), Double.class, Float.class, BigDecimal.class, BigInteger.class);
     add(new DateType(), LocalDate.class, java.sql.Date.class);
     add(new DateTimeType(), Instant.class, OffsetDateTime.class, ZonedDateTime.class, Timestamp.class, java.util.Date.class, LocalDateTime.class);
 
@@ -82,26 +87,54 @@ public Schema<?> createSchema() {
   }
 
   private class BoolType implements KnownType {
+    @Override
+    public Schema<?> createSchema() {
+      return new BooleanSchema().nullable(Boolean.FALSE);
+    }
+  }
+
+  private class BooleanType implements KnownType {
     @Override
     public Schema<?> createSchema() {
       return new BooleanSchema();
     }
   }
 
+  private class IntType implements KnownType {
+    @Override
+    public Schema<?> createSchema() {
+      return new IntegerSchema().nullable(Boolean.FALSE);
+    }
+  }
+
   private class IntegerType implements KnownType {
     @Override
     public Schema<?> createSchema() {
       return new IntegerSchema();
     }
   }
 
+  private class PLongType implements KnownType {
+    @Override
+    public Schema<?> createSchema() {
+      return new IntegerSchema().format("int64").nullable(Boolean.FALSE);
+    }
+  }
+
   private class LongType implements KnownType {
     @Override
     public Schema<?> createSchema() {
       return new IntegerSchema().format("int64");
     }
   }
 
+  private class PNumberType implements KnownType {
+    @Override
+    public Schema<?> createSchema() {
+      return new NumberSchema().nullable(Boolean.FALSE);
+    }
+  }
+
   private class NumberType implements KnownType {
     @Override
     public Schema<?> createSchema() {

src/main/java/io/dinject/javalin/generator/openapi/SchemaDocBuilder.java

@@ -22,6 +22,8 @@
 import javax.lang.model.util.ElementFilter;
 import javax.lang.model.util.Elements;
 import javax.lang.model.util.Types;
+import javax.validation.constraints.Email;
+import javax.validation.constraints.Size;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -217,12 +219,43 @@ private ObjectSchema createObjectSchema(TypeMirror objectType) {
     Element element = types.asElement(objectType);
     for (VariableElement field : allFields(element)) {
       Schema<?> propSchema = toSchema(field.asType());
-      // max,min,required,deprecated ?
+      if (isNotNullable(field)) {
+        propSchema.setNullable(Boolean.FALSE);
+      }
+      setLengthMinMax(field, propSchema);
+      setFormatFromValidation(field, propSchema);
       objectSchema.addProperties(field.getSimpleName().toString(), propSchema);
     }
     return objectSchema;
   }
 
+  private void setFormatFromValidation(Element element, Schema<?> propSchema) {
+    if (element.getAnnotation(Email.class) != null) {
+      propSchema.setFormat("email");
+    }
+  }
+
+  private void setLengthMinMax(Element element, Schema<?> propSchema) {
+    final Size size = element.getAnnotation(Size.class);
+    if (size != null) {
+      if (size.min() > 0) {
+        propSchema.setMinLength(size.min());
+      }
+      if (size.max() > 0) {
+        propSchema.setMaxLength(size.max());
+      }
+    }
+  }
+
+  private boolean isNotNullable(Element element) {
+    if (element.getAnnotation(org.jetbrains.annotations.NotNull.class) != null) {
+      return true;
+    }
+    if (element.getAnnotation(javax.validation.constraints.NotNull.class) != null) {
+      return true;
+    }
+    return false;
+  }
 
   /**
    * Gather all the fields (properties) for the given bean element.