Add custom validation exception traits in new codegen-traits package (#4321)

jasgin · web-flow · commit 4ac79e62f0aa · 2025-10-03T15:15:32.000-04:00
## Motivation and Context   Extension of #4317. This PR will add the traits and the #4317 will be used to add the validation and codegen. Deferring moving existing traits to this new package to another PR to avoid clashing refactors with features. ## Description  ## Testing    ## Checklist  - [x] For changes to the smithy-rs codegen or runtime crates, I have created a changelog entry Markdown file in the `.changelog` directory, specifying "client," "server," or both in the `applies_to` key. - [x] For changes to the AWS SDK, generated SDK code, or SDK runtime crates, I have created a changelog entry Markdown file in the `.changelog` directory, specifying "aws-sdk-rust" in the `applies_to` key. ---- _By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice._
diff --git a/.changelog/1759416345.md b/.changelog/1759416345.md
@@ -0,0 +1,11 @@
+---
+applies_to: ["server"]
+authors: ["jasgin"]
+references: ["smithy-rs#4321"]
+breaking: false
+new_feature: true
+bug_fix: false
+---
+
+Adds the custom traits `@validationException`, `@validationMessage`, `@validationFieldList`, `@validationFieldName`, and `@validationFieldMessage`
+for defining custom validation exceptions.
diff --git a/codegen-server/build.gradle.kts b/codegen-server/build.gradle.kts
@@ -16,6 +16,7 @@ extra["moduleName"] = "software.amazon.smithy.rust.codegen.server"
 
 dependencies {
     implementation(project(":codegen-core"))
+    implementation(project(":codegen-traits"))
     implementation(libs.smithy.aws.traits)
     implementation(libs.smithy.protocol.test.traits)
     implementation(libs.smithy.protocol.traits)
diff --git a/codegen-traits/build.gradle.kts b/codegen-traits/build.gradle.kts
@@ -0,0 +1,18 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+plugins {
+    id("smithy-rs.kotlin-conventions")
+    id("smithy-rs.publishing-conventions")
+}
+
+description = "Smithy traits for Rust code generation"
+extra["displayName"] = "Smithy :: Rust :: Codegen :: Traits"
+extra["moduleName"] = "software.amazon.smithy.rust.codegen.traits"
+
+dependencies {
+    implementation(libs.smithy.model)
+    testImplementation(libs.junit.jupiter)
+}
diff --git a/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationExceptionTrait.kt b/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationExceptionTrait.kt
@@ -0,0 +1,33 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.node.Node
+import software.amazon.smithy.model.shapes.ShapeId
+import software.amazon.smithy.model.traits.AbstractTrait
+import software.amazon.smithy.model.traits.Trait
+
+class ValidationExceptionTrait(
+    sourceLocation: SourceLocation,
+) : AbstractTrait(ID, sourceLocation) {
+    companion object {
+        val ID: ShapeId = ShapeId.from("smithy.rust.codegen.traits#validationException")
+    }
+
+    override fun createNode(): Node = Node.objectNode()
+
+    class Provider : AbstractTrait.Provider(ID) {
+        override fun createTrait(
+            target: ShapeId,
+            value: Node,
+        ): Trait {
+            val result = ValidationExceptionTrait(value.sourceLocation)
+            result.setNodeCache(value)
+            return result
+        }
+    }
+}
diff --git a/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldListTrait.kt b/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldListTrait.kt
@@ -0,0 +1,33 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.node.Node
+import software.amazon.smithy.model.shapes.ShapeId
+import software.amazon.smithy.model.traits.AbstractTrait
+import software.amazon.smithy.model.traits.Trait
+
+class ValidationFieldListTrait(
+    sourceLocation: SourceLocation,
+) : AbstractTrait(ID, sourceLocation) {
+    companion object {
+        val ID: ShapeId = ShapeId.from("smithy.rust.codegen.traits#validationFieldList")
+    }
+
+    override fun createNode(): Node = Node.objectNode()
+
+    class Provider : AbstractTrait.Provider(ID) {
+        override fun createTrait(
+            target: ShapeId,
+            value: Node,
+        ): Trait {
+            val result = ValidationFieldListTrait(value.sourceLocation)
+            result.setNodeCache(value)
+            return result
+        }
+    }
+}
diff --git a/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldMessageTrait.kt b/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldMessageTrait.kt
@@ -0,0 +1,33 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.node.Node
+import software.amazon.smithy.model.shapes.ShapeId
+import software.amazon.smithy.model.traits.AbstractTrait
+import software.amazon.smithy.model.traits.Trait
+
+class ValidationFieldMessageTrait(
+    sourceLocation: SourceLocation,
+) : AbstractTrait(ID, sourceLocation) {
+    companion object {
+        val ID: ShapeId = ShapeId.from("smithy.rust.codegen.traits#validationFieldMessage")
+    }
+
+    override fun createNode(): Node = Node.objectNode()
+
+    class Provider : AbstractTrait.Provider(ID) {
+        override fun createTrait(
+            target: ShapeId,
+            value: Node,
+        ): Trait {
+            val result = ValidationFieldMessageTrait(value.sourceLocation)
+            result.setNodeCache(value)
+            return result
+        }
+    }
+}
diff --git a/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldNameTrait.kt b/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldNameTrait.kt
@@ -0,0 +1,33 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.node.Node
+import software.amazon.smithy.model.shapes.ShapeId
+import software.amazon.smithy.model.traits.AbstractTrait
+import software.amazon.smithy.model.traits.Trait
+
+class ValidationFieldNameTrait(
+    sourceLocation: SourceLocation,
+) : AbstractTrait(ID, sourceLocation) {
+    companion object {
+        val ID: ShapeId = ShapeId.from("smithy.rust.codegen.traits#validationFieldName")
+    }
+
+    override fun createNode(): Node = Node.objectNode()
+
+    class Provider : AbstractTrait.Provider(ID) {
+        override fun createTrait(
+            target: ShapeId,
+            value: Node,
+        ): Trait {
+            val result = ValidationFieldNameTrait(value.sourceLocation)
+            result.setNodeCache(value)
+            return result
+        }
+    }
+}
diff --git a/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationMessageTrait.kt b/codegen-traits/src/main/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationMessageTrait.kt
@@ -0,0 +1,33 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.node.Node
+import software.amazon.smithy.model.shapes.ShapeId
+import software.amazon.smithy.model.traits.AbstractTrait
+import software.amazon.smithy.model.traits.Trait
+
+class ValidationMessageTrait(
+    sourceLocation: SourceLocation,
+) : AbstractTrait(ID, sourceLocation) {
+    companion object {
+        val ID: ShapeId = ShapeId.from("smithy.rust.codegen.traits#validationMessage")
+    }
+
+    override fun createNode(): Node = Node.objectNode()
+
+    class Provider : AbstractTrait.Provider(ID) {
+        override fun createTrait(
+            target: ShapeId,
+            value: Node,
+        ): Trait {
+            val result = ValidationMessageTrait(value.sourceLocation)
+            result.setNodeCache(value)
+            return result
+        }
+    }
+}
diff --git a/codegen-traits/src/main/resources/META-INF/smithy/manifest b/codegen-traits/src/main/resources/META-INF/smithy/manifest
@@ -0,0 +1 @@
+validation-exception.smithy
diff --git a/codegen-traits/src/main/resources/META-INF/smithy/services/software.amazon.smithy.model.traits.TraitService b/codegen-traits/src/main/resources/META-INF/smithy/services/software.amazon.smithy.model.traits.TraitService
@@ -0,0 +1,5 @@
+software.amazon.smithy.rust.codegen.server.smithy.traits.ValidationExceptionTrait$Provider
+software.amazon.smithy.rust.codegen.server.smithy.traits.ValidationMessageTrait$Provider
+software.amazon.smithy.rust.codegen.server.smithy.traits.ValidationFieldListTrait$Provider
+software.amazon.smithy.rust.codegen.server.smithy.traits.ValidationFieldNameTrait$Provider
+software.amazon.smithy.rust.codegen.server.smithy.traits.ValidationFieldMessageTrait$Provider
diff --git a/codegen-traits/src/main/resources/META-INF/smithy/validation-exception.smithy b/codegen-traits/src/main/resources/META-INF/smithy/validation-exception.smithy
@@ -0,0 +1,27 @@
+$version: "2.0"
+
+namespace smithy.rust.codegen.traits
+
+/// Marks a structure as a custom validation exception that can replace
+/// smithy.framework#ValidationException in operation error lists.
+@trait(selector: "structure")
+structure validationException {}
+
+/// Marks a String member as the primary message field for a validation exception.
+/// Exactly one member in a @validationException structure must have this trait.
+@trait(selector: "structure[trait|smithy.rust.codegen.traits#validationException] > member")
+structure validationMessage {}
+
+/// Marks a member as containing the list of field-level validation errors.
+/// The target shape must be a String, List<String>, or List<Structure> where
+/// the structure contains validation field information.
+@trait(selector: "structure > member")
+structure validationFieldList {}
+
+/// Marks a String member as containing the field name in a validation field structure.
+@trait(selector: "structure > member")
+structure validationFieldName {}
+
+/// Marks a String member as containing the field error message in a validation field structure.
+@trait(selector: "structure > member")
+structure validationFieldMessage {}
diff --git a/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationExceptionTraitTest.kt b/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationExceptionTraitTest.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.shapes.ShapeId
+
+class ValidationExceptionTraitTest {
+    @Test
+    fun testValidationExceptionTrait() {
+        val trait = ValidationExceptionTrait(SourceLocation.NONE)
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationException"), trait.toShapeId())
+
+        // Test the Provider
+        val provider = ValidationExceptionTrait.Provider()
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationException"), provider.shapeId)
+    }
+}
diff --git a/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldListTraitTest.kt b/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldListTraitTest.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.shapes.ShapeId
+
+class ValidationFieldListTraitTest {
+    @Test
+    fun testValidationFieldListTrait() {
+        val trait = ValidationFieldListTrait(SourceLocation.NONE)
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationFieldList"), trait.toShapeId())
+
+        // Test the Provider
+        val provider = ValidationFieldListTrait.Provider()
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationFieldList"), provider.shapeId)
+    }
+}
diff --git a/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldMessageTraitTest.kt b/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldMessageTraitTest.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.shapes.ShapeId
+
+class ValidationFieldMessageTraitTest {
+    @Test
+    fun testValidationFieldMessageTrait() {
+        val trait = ValidationFieldMessageTrait(SourceLocation.NONE)
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationFieldMessage"), trait.toShapeId())
+
+        // Test the Provider
+        val provider = ValidationFieldMessageTrait.Provider()
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationFieldMessage"), provider.shapeId)
+    }
+}
diff --git a/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldNameTraitTest.kt b/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationFieldNameTraitTest.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.shapes.ShapeId
+
+class ValidationFieldNameTraitTest {
+    @Test
+    fun testValidationFieldNameTrait() {
+        val trait = ValidationFieldNameTrait(SourceLocation.NONE)
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationFieldName"), trait.toShapeId())
+
+        // Test the Provider
+        val provider = ValidationFieldNameTrait.Provider()
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationFieldName"), provider.shapeId)
+    }
+}
diff --git a/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationMessageTraitTest.kt b/codegen-traits/src/test/kotlin/software/amazon/smithy/rust/codegen/traits/ValidationMessageTraitTest.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.rust.codegen.traits
+
+import org.junit.jupiter.api.Assertions.assertEquals
+import org.junit.jupiter.api.Test
+import software.amazon.smithy.model.SourceLocation
+import software.amazon.smithy.model.shapes.ShapeId
+
+class ValidationMessageTraitTest {
+    @Test
+    fun testValidationMessageTrait() {
+        val trait = ValidationMessageTrait(SourceLocation.NONE)
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationMessage"), trait.toShapeId())
+
+        // Test the Provider
+        val provider = ValidationMessageTrait.Provider()
+        assertEquals(ShapeId.from("smithy.rust.codegen.traits#validationMessage"), provider.shapeId)
+    }
+}
diff --git a/gradle.properties b/gradle.properties
@@ -17,4 +17,4 @@ allowLocalDeps=false
 # Avoid registering dependencies/plugins/tasks that are only used for testing purposes
 isTestingEnabled=true
 # codegen publication version
-codegenVersion=0.1.2
+codegenVersion=0.1.3
diff --git a/settings.gradle.kts b/settings.gradle.kts
@@ -17,6 +17,7 @@ include(":codegen-server-test")
 // due to https://github.com/gradle/gradle/issues/847
 include(":codegen-server-test:codegen-server-test-python")
 include(":codegen-server-test:codegen-server-test-typescript")
+include(":codegen-traits")
 include(":rust-runtime")
 include(":aws:rust-runtime")
 // NOTE: we rename the aws/rust-runtime project so that it ends up with different GAV
