Unverified Commit 2d5bf6fc authored by david-perez's avatar david-perez Committed by GitHub
Browse files

Only generate `@error` `message` getter when defined in the model (#1441) 

We are currently generating a useless `message` getter that returns
`None` even when the `message` field is not defined in the model.
Granted, in the client this field is _almost always_ there, because the
`AddErrorMessage` model transformer is applied unless the user opts out
in their `smithy-build.json`.
parent 1875448d

codegen/src/main/kotlin/software/amazon/smithy/rust/codegen/smithy/generators/error/ErrorGenerator.kt

+14 −13
Original line number Diff line number Diff line
@@ -69,13 +69,6 @@ class ErrorGenerator( 
        val symbol = symbolProvider.toSymbol(shape)

        val messageShape = shape.errorMessageMember()

        val errorKindT = RuntimeType.errorKind(symbolProvider.config().runtimeConfig)

        val (returnType, message) = messageShape?.let {

            if (symbolProvider.toSymbol(messageShape).isOptional()) {

                "Option<&str>" to "self.${symbolProvider.toMemberName(it)}.as_deref()"

            } else {

                "&str" to "self.${symbolProvider.toMemberName(it)}.as_ref()"

            }

        } ?: "Option<&str>" to "None"

        writer.rustBlock("impl ${symbol.name}") {

            val retryKindWriteable = shape.modeledRetryKind(error)?.writable(symbolProvider.config().runtimeConfig)

            if (retryKindWriteable != null) {
@@ -84,12 +77,20 @@ class ErrorGenerator( 
                    retryKindWriteable(this)

                }

            }

            if (messageShape != null) {

                val (returnType, message) = if (symbolProvider.toSymbol(messageShape).isOptional()) {

                    "Option<&str>" to "self.${symbolProvider.toMemberName(messageShape)}.as_deref()"

                } else {

                    "&str" to "self.${symbolProvider.toMemberName(messageShape)}.as_ref()"

                }



                rust(

                    """

                    /// Returns the error message.

                    pub fn message(&self) -> $returnType { $message }

                    """

                )

            }



            /*

             * If we're generating for a server, the `name` method is added to enable

codegen/src/main/kotlin/software/amazon/smithy/rust/codegen/smithy/transformers/AddErrorMessage.kt

+3 −3
Original line number Diff line number Diff line
@@ -18,11 +18,11 @@ import java.util.logging.Logger 
fun StructureShape.errorMessageMember(): MemberShape? = this.getMember("message").or { this.getMember("Message") }.orNull()



/**

 * Ensure that all errors have error messages

 * Ensure that all errors have error messages.

 *

 * Not all errors are modeled with an error message field. However, in many cases, the server can still send an error.

 * If an error, specifically, a structure shape with the error trait does not have a member `message` or `Message`,

 * this transformer will add a `message` member targetting a string.

 * this transformer will add a `message` member targeting a string.

 *

 * This ensures that we always generate a modeled error message field enabling end users to easily extract the error

 * message when present.
@@ -33,7 +33,7 @@ object AddErrorMessage { 
    private val logger = Logger.getLogger("AddErrorMessage")



    /**

     * Ensure that all errors have error messages

     * Ensure that all errors have error messages.

     */

    fun transform(model: Model): Model {

        return ModelTransformer.create().mapShapes(model) { shape ->