From b0a0494a2848892e8e2a5b2a940546338a05c788 Mon Sep 17 00:00:00 2001
From: kodemon <hi@kodemon.net>
Date: Fri, 18 Apr 2025 22:56:29 +0000
Subject: [PATCH] feat: add error response support to actions

---
 deno.json              | 2 +-
 libraries/action.ts    | 6 ++++--
 libraries/api.ts       | 3 +++
 tests/mocks/actions.ts | 4 ++++
 tests/route.test.ts    | 4 ++++
 5 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/deno.json b/deno.json
index 41ef5ae..50e76af 100644
--- a/deno.json
+++ b/deno.json
@@ -1,6 +1,6 @@
 {
   "name": "@valkyr/relay",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "exports": {
     ".": "./mod.ts",
     "./http": "./adapters/http.ts"
diff --git a/libraries/action.ts b/libraries/action.ts
index eca7787..e31c26f 100644
--- a/libraries/action.ts
+++ b/libraries/action.ts
@@ -1,5 +1,7 @@
 import z, { ZodObject, ZodRawShape } from "zod";
 
+import { RelayError } from "./errors.ts";
+
 export class Action<TActionState extends ActionState = ActionState> {
   constructor(readonly state: TActionState) {}
 
@@ -61,5 +63,5 @@ type ActionState = {
 };
 
 type ActionHandlerFn<TInput = any, TOutput = any> = TInput extends ZodObject
-  ? (input: z.infer<TInput>) => TOutput extends ZodObject ? Promise<z.infer<TOutput>> : Promise<void>
-  : () => TOutput extends ZodObject ? Promise<z.infer<TOutput>> : Promise<void>;
+  ? (input: z.infer<TInput>) => TOutput extends ZodObject ? Promise<z.infer<TOutput> | RelayError> : Promise<void | RelayError>
+  : () => TOutput extends ZodObject ? Promise<z.infer<TOutput> | RelayError> : Promise<void | RelayError>;
diff --git a/libraries/api.ts b/libraries/api.ts
index 41b8b1a..df5000b 100644
--- a/libraries/api.ts
+++ b/libraries/api.ts
@@ -130,6 +130,9 @@ export class Api<TRoutes extends Route[]> {
           return toResponse(new InternalServerError(`Action '${action.state.name}' is missing handler.`));
         }
         const output = await action.state.handle(result.data);
+        if (output instanceof RelayError) {
+          return toResponse(output);
+        }
         for (const key in output) {
           context[key] = output[key];
         }
diff --git a/tests/mocks/actions.ts b/tests/mocks/actions.ts
index 036904f..62d1906 100644
--- a/tests/mocks/actions.ts
+++ b/tests/mocks/actions.ts
@@ -1,12 +1,16 @@
 import z from "zod";
 
 import { action } from "../../libraries/action.ts";
+import { BadRequestError } from "../../mod.ts";
 
 export const addTwoNumbers = action
   .make("addTwoNumbers")
   .input({ a: z.number(), b: z.number() })
   .output({ added: z.number() })
   .handle(async ({ a, b }) => {
+    if (a < 0 || b < 0) {
+      return new BadRequestError("Invalid input numbers added");
+    }
     return {
       added: a + b,
     };
diff --git a/tests/route.test.ts b/tests/route.test.ts
index 13530f4..9090264 100644
--- a/tests/route.test.ts
+++ b/tests/route.test.ts
@@ -52,4 +52,8 @@ describe("Relay", () => {
   it("should successfully run .actions", async () => {
     assertEquals(await relay.get("/add-two", { a: 1, b: 1 }), 2);
   });
+
+  it("should reject .actions with error", async () => {
+    assertEquals(await relay.get("/add-two", { a: -1, b: 1 }), 2);
+  });
 });