Improve register handler errors API (#201)

.changeset/big-glasses-hang.md

@@ -0,0 +1,5 @@
+---
+"@saleor/app-sdk": minor
+---
+
+Register handler hooks will now respond with errors parsable by the dashboard. "Body" in error was removed, so client code can provide message and status.

docs/api-handlers.md

@@ -67,7 +67,8 @@ export default createAppRegisterHandler({
   allowedSaleorUrls: ["https://your-saleor.saleor.cloud/graphql/"], // optional, see options below
   async onRequestVerified(req, { authData, respondWithError }) {
     await doSomethingAndBlockInstallation(authData.token).catch((err) => {
-      throw respondWithError({ body: "Error, installation will fail" });
+      // Return this method to break installation flow and show error in the Dashboard
+      return respondWithError({ message: "Error, installation will fail" });
     });
   },
 });
@@ -93,7 +94,7 @@ export type CreateAppRegisterHandlerOptions = {
       authToken?: string;
       saleorDomain?: string;
       saleorApiUrl?: string;
-      respondWithError: ({ status, message, body }) => never; // should throw
+      respondWithError: ({ status, message }) => never; // will throw
     }
   ): Promise<void>;
   /**
@@ -104,7 +105,7 @@ export type CreateAppRegisterHandlerOptions = {
     request: Request,
     context: {
       authData: AuthData;
-      respondWithError: ({ status, message, body }) => never; // should throw
+      respondWithError: ({ status, message }) => never; // will throw
     }
   ): Promise<void>;
   /**
@@ -115,7 +116,7 @@ export type CreateAppRegisterHandlerOptions = {
     request: Request,
     context: {
       authData: AuthData;
-      respondWithError: ({ status, message, body }) => never; // should throw
+      respondWithError: ({ status, message }) => never; // will throw
     }
   ): Promise<void>;
   /**
@@ -127,7 +128,7 @@ export type CreateAppRegisterHandlerOptions = {
     context: {
       authData: AuthData;
       error: unknown;
-      respondWithError: ({ status, message, body }) => never; // should throw
+      respondWithError: ({ status, message }) => never; // will throw
     }
   ): Promise<void>;
 };

src/handlers/next/create-app-register-handler.test.ts

@@ -219,13 +219,12 @@ describe("create-app-register-handler", () => {
           context: {
             respondWithError(params: { status: number; body: string; message: string }): Error;
           }
-        ) => {
-          throw context.respondWithError({
+        ) =>
+          context.respondWithError({
             status: 401,
             body: "test",
             message: "test message",
-          });
-        }
+          })
       );
 
       const { res, req } = createMocks({
@@ -253,7 +252,13 @@ describe("create-app-register-handler", () => {
       await handler(req, res);
 
       expect(res._getStatusCode()).toBe(401);
-      expect(res._getData()).toBe("test");
+      expect(res._getData()).toEqual({
+        success: false,
+        error: {
+          code: "REGISTER_HANDLER_HOOK_ERROR",
+          message: "test message",
+        },
+      });
     });
   });
 });

src/handlers/next/create-app-register-handler.ts

@@ -16,33 +16,49 @@ const debug = createDebug("createAppRegisterHandler");
 
 type HookCallbackErrorParams = {
   status?: number;
-  body?: object;
   message?: string;
 };
 
 class RegisterCallbackError extends Error {
   public status = 500;
 
-  public body: object = {};
-
   constructor(errorParams: HookCallbackErrorParams) {
     super(errorParams.message);
 
     if (errorParams.status) {
       this.status = errorParams.status;
     }
-
-    if (errorParams.body) {
-      this.body = errorParams.body;
-    }
   }
 }
 
-const createCallbackError = (params: HookCallbackErrorParams) => new RegisterCallbackError(params);
+const createCallbackError = (params: HookCallbackErrorParams) => {
+  throw new RegisterCallbackError(params);
+};
+
+export type RegisterHandlerResponseBody = {
+  success: boolean;
+  error?: {
+    code?: string;
+    message?: string;
+  };
+};
+export const createRegisterHandlerResponseBody = (
+  success: boolean,
+  error?: RegisterHandlerResponseBody["error"]
+): RegisterHandlerResponseBody => ({
+  success,
+  error,
+});
 
 const handleHookError = (e: RegisterCallbackError | unknown) => {
   if (e instanceof RegisterCallbackError) {
-    return new Response(e.body, { status: e.status });
+    return new Response(
+      createRegisterHandlerResponseBody(false, {
+        code: "REGISTER_HANDLER_HOOK_ERROR",
+        message: e.message,
+      }),
+      { status: e.status }
+    );
   }
   return Response.InternalServerError("Error during app installation");
 };
@@ -141,27 +157,24 @@ export const createAppRegisterHandler = ({
     if (!validateAllowSaleorUrls(saleorApiUrl, allowedSaleorUrls)) {
       debug("Validation of URL %s against allowSaleorUrls param resolves to false, throwing");
 
-      return Response.Forbidden({
-        success: false,
-        error: {
+      return Response.Forbidden(
+        createRegisterHandlerResponseBody(false, {
           code: "SALEOR_URL_PROHIBITED",
           message: "This app expects to be installed only in allowed saleor instances",
-        },
-      });
+        })
+      );
     }
 
     const { configured: aplConfigured } = await apl.isConfigured();
 
     if (!aplConfigured) {
       debug("The APL has not been configured");
+
       return new Response(
-        {
-          success: false,
-          error: {
-            code: "APL_NOT_CONFIGURED",
-            message: "APL_NOT_CONFIGURED. App is configured properly. Check APL docs for help.",
-          },
-        },
+        createRegisterHandlerResponseBody(false, {
+          code: "APL_NOT_CONFIGURED",
+          message: "APL_NOT_CONFIGURED. App is configured properly. Check APL docs for help.",
+        }),
         {
           status: 503,
         }
@@ -172,14 +185,11 @@ export const createAppRegisterHandler = ({
     const appId = await getAppId({ saleorApiUrl, token: authToken });
     if (!appId) {
       return new Response(
-        {
-          success: false,
-          error: {
-            code: "UNKNOWN_APP_ID",
-            message:
-              "The auth data given during registration request could not be used to fetch app ID.",
-          },
-        },
+        createRegisterHandlerResponseBody(false, {
+          code: "UNKNOWN_APP_ID",
+          message:
+            "The auth data given during registration request could not be used to fetch app ID.",
+        }),
         {
           status: 401,
         }
@@ -190,13 +200,10 @@ export const createAppRegisterHandler = ({
     const jwks = await fetchRemoteJwks(saleorApiUrl);
     if (!jwks) {
       return new Response(
-        {
-          success: false,
-          error: {
-            code: "JWKS_NOT_AVAILABLE",
-            message: "Can't fetch the remote JWKS.",
-          },
-        },
+        createRegisterHandlerResponseBody(false, {
+          code: "JWKS_NOT_AVAILABLE",
+          message: "Can't fetch the remote JWKS.",
+        }),
         {
           status: 401,
         }
@@ -262,17 +269,16 @@ export const createAppRegisterHandler = ({
         }
       }
 
-      return Response.InternalServerError({
-        success: false,
-        error: {
+      return Response.InternalServerError(
+        createRegisterHandlerResponseBody(false, {
           message: "Registration failed: could not save the auth data.",
-        },
-      });
+        })
+      );
     }
 
     debug("Register  complete");
 
-    return Response.OK({ success: true });
+    return Response.OK(createRegisterHandlerResponseBody(true));
   };
 
   return toNextHandler([