feat(validation): add case class from string (#244)

With LatLon case class, we can now validate and parse strings into case classes.
cheleb · Nov 28, 2024 · 3b88501 · 3b88501
1 parent fca416c
commit 3b88501
Show file tree

Hide file tree

Showing 2 changed files with 68 additions and 2 deletions.
diff --git a/examples/client/src/main/scala/samples/Validation.scala b/examples/client/src/main/scala/samples/Validation.scala
@@ -9,21 +9,54 @@ import io.github.iltotore.iron.constraint.all.*
 
 val validation = {
 
+  case class LatLon(lat: Double, lon: Double) {
+    override def toString: String = s"$lat,$lon"
+  }
+
   given Form[CurrencyCode] = stringForm(CurrencyCode(_))
 
+  given Form[LatLon] = stringFormWithValidation(using
+    new Validator[LatLon] {
+      override def validate(value: String): Either[String, LatLon] = {
+        value.split(",") match {
+          case Array(lat, lon) =>
+            (
+              lat.toDoubleOption.toRight("Invalid latitude"),
+              lon.toDoubleOption.toRight("Invalid longitude")
+            ) match {
+              case (Right(lat), Right(lon)) => Right(LatLon(lat, lon))
+              case (Left(latError), Left(rightError)) =>
+                Left(s"$latError and $rightError")
+              case (Left(latError), _) => Left(latError)
+              case (_, Left(lonError)) => Left(lonError)
+            }
+          case _ => Left("Invalid format")
+        }
+      }
+    }
+  )
+
   case class IronSample(
       curenncyCode: CurrencyCode,
       optional: Option[String],
       optionalInt: Option[Int],
       doubleGreaterThanEight: Double :| GreaterEqual[8.0],
-      optionalDoublePositive: Option[Double :| Positive]
+      optionalDoublePositive: Option[Double :| Positive],
+      latLong: LatLon
   )
 
   given Defaultable[Double :| GreaterEqual[8.0]] with
     def default: Double :| GreaterEqual[8.0] = 8.0
 
   val ironSampleVar = Var(
-    IronSample(CurrencyCode("Eur"), Some("name"), Some(1), 9.1, Some(1))
+    IronSample(
+      CurrencyCode("Eur"),
+      Some("name"),
+      Some(1),
+      9.1,
+      Some(1),
+      LatLon(1, 2)
+    )
   )
 
   val errorBus = ironSampleVar.errorBus

diff --git a/modules/core/src/main/scala/dev/cheleb/scalamigen/package.scala b/modules/core/src/main/scala/dev/cheleb/scalamigen/package.scala
@@ -6,6 +6,9 @@ import com.raquo.laminar.api.L.*
 import com.raquo.laminar.nodes.ReactiveHtmlElement
 import org.scalajs.dom.HTMLElement
 
+/** A form for a type A, no validation. Convenient to use for Opaque types. If
+  * you need validation, use a Form with a ValidationEvent.
+  */
 def stringForm[A](to: String => A) = new Form[A]:
   override def render(
       path: List[Symbol],
@@ -97,6 +100,36 @@ def enumForm[A](values: Array[A], f: Int => A) = new Form[A] {
 
 }
 
+/** A form for a type A, no validation. Convenient to use for Opaque types. If
+  * you need validation, use a Form with a ValidationEvent.
+  */
+def stringFormWithValidation[A](using
+    validator: Validator[A]
+) = new Form[A]:
+  override def render(
+      path: List[Symbol],
+      variable: Var[A],
+      syncParent: () => Unit
+  )(using
+      factory: WidgetFactory,
+      errorBus: EventBus[(String, ValidationEvent)]
+  ): HtmlElement =
+    factory.renderText.amend(
+      value <-- variable.signal.map(_.toString),
+      onInput.mapToValue.map(validator.validate) --> {
+        case Right(v) =>
+          variable.set(v)
+          errorBus.emit(
+            (path.key, ValidEvent)
+          )
+          syncParent()
+        case Left(err) =>
+          errorBus.emit(
+            (path.key, InvalideEvent(err))
+          )
+      }
+    )
+
 /** Extension methods for the Var class.
   */
 extension [A](va: Var[A])