fix: Schema error formatter type (fastify#4570)

* refactor: type SchemaErrorFormatter

* fix: refactor and fix type SchemaErrorDataVar

* fix: type test for validationContext

Author: cm-ayf

fastify.d.ts

@@ -20,15 +20,15 @@ import { FastifyRegister, FastifyRegisterOptions, RegisterOptions } from './type
 import { FastifyReply } from './types/reply'
 import { FastifyRequest, RequestGenericInterface } from './types/request'
 import { RouteHandler, RouteHandlerMethod, RouteOptions, RouteShorthandMethod, RouteShorthandOptions, RouteShorthandOptionsWithHandler, RouteGenericInterface } from './types/route'
-import { FastifySchema, FastifySchemaCompiler, FastifySchemaValidationError } from './types/schema'
+import { FastifySchema, FastifySchemaCompiler, SchemaErrorDataVar, SchemaErrorFormatter } from './types/schema'
 import { FastifyServerFactory, FastifyServerFactoryHandler } from './types/serverFactory'
 import { FastifyTypeProvider, FastifyTypeProviderDefault } from './types/type-provider'
 import { HTTPMethods, RawServerBase, RawRequestDefaultExpression, RawReplyDefaultExpression, RawServerDefault, ContextConfigDefault, RequestBodyDefault, RequestQuerystringDefault, RequestParamsDefault, RequestHeadersDefault } from './types/utils'
 
 declare module '@fastify/error' {
   interface FastifyError {
     validation?: fastify.ValidationResult[];
-    validationContext?: 'body' | 'headers' | 'parameters' | 'querystring';
+    validationContext?: SchemaErrorDataVar;
   }
 }
 
@@ -149,7 +149,7 @@ declare namespace fastify {
       res: FastifyReply<RawServer, RawRequestDefaultExpression<RawServer>, RawReplyDefaultExpression<RawServer>, RequestGeneric, FastifyContextConfig, SchemaCompiler, TypeProvider>
     ) => void,
     rewriteUrl?: (req: RawRequestDefaultExpression<RawServer>) => string,
-    schemaErrorFormatter?: (errors: FastifySchemaValidationError[], dataVar: string) => Error,
+    schemaErrorFormatter?: SchemaErrorFormatter,
     /**
      * listener to error events emitted by client connections
      */

test/types/fastify.test-d.ts

@@ -240,7 +240,7 @@ expectAssignable<ValidationResult>(ajvErrorObject)
 expectAssignable<FastifyError['validation']>([ajvErrorObject])
 expectAssignable<FastifyError['validationContext']>('body')
 expectAssignable<FastifyError['validationContext']>('headers')
-expectAssignable<FastifyError['validationContext']>('parameters')
+expectAssignable<FastifyError['validationContext']>('params')
 expectAssignable<FastifyError['validationContext']>('querystring')
 
 const routeGeneric: RouteGenericInterface = {}

types/instance.d.ts

@@ -13,8 +13,8 @@ import {
   FastifySchema,
   FastifySchemaCompiler,
   FastifySchemaControllerOptions,
-  FastifySchemaValidationError,
-  FastifySerializerCompiler
+  FastifySerializerCompiler,
+  SchemaErrorFormatter
 } from './schema'
 import {
   FastifyTypeProvider,
@@ -530,7 +530,7 @@ export interface FastifyInstance<
   /*
   * Set the schema error formatter for all routes.
   */
-  setSchemaErrorFormatter(errorFormatter: (errors: FastifySchemaValidationError[], dataVar: string) => Error): FastifyInstance<RawServer, RawRequest, RawReply, Logger, TypeProvider>;
+  setSchemaErrorFormatter(errorFormatter: SchemaErrorFormatter): FastifyInstance<RawServer, RawRequest, RawReply, Logger, TypeProvider>;
   /**
    * Add a content type parser
    */

types/route.d.ts

@@ -1,7 +1,7 @@
 import { FastifyInstance } from './instance'
 import { FastifyRequest, RequestGenericInterface } from './request'
 import { FastifyReply, ReplyGenericInterface } from './reply'
-import { FastifySchema, FastifySchemaCompiler, FastifySchemaValidationError, FastifySerializerCompiler } from './schema'
+import { FastifySchema, FastifySchemaCompiler, FastifySerializerCompiler, SchemaErrorFormatter } from './schema'
 import { HTTPMethods, RawServerBase, RawServerDefault, RawRequestDefaultExpression, RawReplyDefaultExpression, ContextConfigDefault } from './utils'
 import { preValidationHookHandler, preHandlerHookHandler, preSerializationHookHandler, onRequestHookHandler, preParsingHookHandler, onResponseHookHandler, onSendHookHandler, onErrorHookHandler, onTimeoutHookHandler } from './hooks'
 import { FastifyError } from '@fastify/error'
@@ -41,8 +41,7 @@ export interface RouteShorthandOptions<
   constraints?: { [name: string]: any },
   prefixTrailingSlash?: 'slash'|'no-slash'|'both';
   errorHandler?: (this: FastifyInstance, error: FastifyError, request: FastifyRequest, reply: FastifyReply) => void;
-  // TODO: Change to actual type.
-  schemaErrorFormatter?: (errors: FastifySchemaValidationError[], dataVar: string) => Error;
+  schemaErrorFormatter?: SchemaErrorFormatter;
 
   // hooks
   onRequest?: onRequestHookHandler<RawServer, RawRequest, RawReply, RouteGeneric, ContextConfig, SchemaCompiler, TypeProvider, Logger> | onRequestHookHandler<RawServer, RawRequest, RawReply, RouteGeneric, ContextConfig, SchemaCompiler, TypeProvider, Logger>[];

types/schema.d.ts

@@ -54,3 +54,7 @@ export interface FastifySchemaControllerOptions{
     buildSerializer?: (externalSchemas: unknown, serializerOptsServerOption: FastifyServerOptions['serializerOpts']) => FastifySerializerCompiler<unknown>;
   };
 }
+
+export type SchemaErrorDataVar = 'body' | 'headers' | 'params' | 'querystring'
+
+export type SchemaErrorFormatter = (errors: FastifySchemaValidationError[], dataVar: SchemaErrorDataVar) => Error