feat: Allow skipping setNotFoundHandler.

Author: ShogunPanda

README.md

@@ -21,6 +21,7 @@ npm install fastify-http-errors-enhanced --save
 
 Register as a plugin, optional providing any of the following options:
 
+- `handle404Errors`: If to set an handler via `setNotFoundHandler`.
 - `hideUnhandledErrors`: If to hide unhandled server errors or returning to the client including stack information. Default is to hide errors when `NODE_ENV` environment variable is `production`.
 - `convertValidationErrors`: Convert validation errors to a structured human readable object. Default is `true`.
 - `convertResponsesValidationErrors`: Convert response validation errors to a structured human readable object. Default is to enable when `NODE_ENV` environment variable is different from `production`.

src/index.ts

@@ -16,6 +16,7 @@ export const plugin = fastifyPlugin(
   function (instance: FastifyInstance, options: FastifyPluginOptions, done: (error?: FastifyError) => void): void {
     const isProduction = process.env.NODE_ENV === 'production'
     const convertResponsesValidationErrors = options.convertResponsesValidationErrors ?? !isProduction
+    const handle404Errors = options.handle404Errors ?? true
 
     const configuration: Configuration = {
       hideUnhandledErrors: options.hideUnhandledErrors ?? isProduction,
@@ -35,7 +36,10 @@ export const plugin = fastifyPlugin(
     })
 
     instance.setErrorHandler(handleErrors)
-    instance.setNotFoundHandler(handleNotFoundError)
+
+    if (handle404Errors) {
+      instance.setNotFoundHandler(handleNotFoundError)
+    }
 
     if (convertResponsesValidationErrors) {
       instance.decorate(kHttpErrorsEnhancedResponseValidations, [])

test/index.test.ts

@@ -1,6 +1,6 @@
 /* eslint-disable @typescript-eslint/no-floating-promises */
 
-import fastify, { FastifyInstance, FastifyPluginOptions } from 'fastify'
+import fastify, { FastifyInstance, FastifyPluginOptions, FastifyReply, FastifyRequest } from 'fastify'
 import {
   BadGatewayError,
   BAD_GATEWAY,
@@ -332,6 +332,40 @@ t.test('Plugin', t => {
       }
     )
 
+    t.test('should correctly install a not found error handler', async t => {
+      const server = await buildServer()
+
+      const response = await server.inject({
+        method: 'POST',
+        url: '/not-found',
+        headers: { 'content-type': 'image/png' }
+      })
+
+      t.equal(response.statusCode, NOT_FOUND)
+      t.same(JSON.parse(response.payload), {
+        statusCode: 404,
+        error: 'Not Found',
+        message: 'Not found.'
+      })
+    })
+
+    t.test('should correctly skip installing a not found error handler', async t => {
+      const server = await buildServer({ handle404Errors: false })
+
+      server.setNotFoundHandler((_: FastifyRequest, reply: FastifyReply) => {
+        reply.code(444).send('NOT FOUND')
+      })
+
+      const response = await server.inject({
+        method: 'POST',
+        url: '/not-found',
+        headers: { 'content-type': 'image/png' }
+      })
+
+      t.equal(response.statusCode, 444)
+      t.same(response.payload, 'NOT FOUND')
+    })
+
     t.test('should correctly parse invalid content type errors', async t => {
       const server = await buildServer()