add warning if CSRF endpoint used when skipped

docs/docs/reference/09-warnings.md

@@ -3,57 +3,13 @@ id: warnings
 title: Warnings
 ---
 
-This is a list of warning output from Auth.js.
+A list of warnings from Auth.js that need your attention.
 
-All warnings indicate things which you should take a look at, but do not inhibit normal operation.
 
----
+## Debug enabled
 
-## Client
+The `debug` option was evaluated to `true`. It adds extra logs in the terminal which is useful in development, but since it can print sensitive information about users, make sure to set this to `false` in production. In Node.js environments, you can for example set `debug: process.env.NODE_ENV !== "production"`. Consult with your runtime/framework on how to set this value correctly.
 
-#### NEXTAUTH_URL
+## CSRF disabled
 
-Environment variable `NEXTAUTH_URL` missing. Please set it in your `.env` file.
-
-:::note
-On [Vercel](https://vercel.com) deployments, we will read the `VERCEL_URL` environment variable, so you won't need to define `NEXTAUTH_URL`.
-:::
-
----
-
-## Server
-
-These warnings are displayed on the terminal.
-
-#### NO_SECRET
-
-In development, we generate a `secret` based on your configuration for convenience. This is volatile and will throw an error in production. [Read more](https://authjs.dev/reference/configuration/auth-config/#secret)
-
-#### TWITTER_OAUTH_2_BETA
-
-Twitter OAuth 2.0 is currently in beta as certain changes might still be necessary. This is not covered by semver. See the docs https://authjs.dev/reference/providers/twitter#oauth-2
-
-#### EXPERIMENTAL_API
-
-Some APIs are still experimental; they may be changed or removed in the future. Use at your own risk.
-
-## Adapter
-
-### ADAPTER_TYPEORM_UPDATING_ENTITIES
-
-This warning occurs when typeorm finds that the provided entities differ from the database entities. By default while not in `production` the typeorm adapter will always synchronize changes made to the entities codefiles.
-
-Disable this warning by setting `synchronize: false` in your typeorm config
-
-Example:
-
-```js title="/pages/api/auth/[...nextauth].js"
-adapter: TypeORMLegacyAdapter({
-  type: 'mysql',
-  username: process.env.DATABASE_USERNAME,
-  password: process.env.DATABASE_PASSWORD,
-  host: process.env.DATABASE_HOST,
-  database: process.env.DATABASE_DB,
-  synchronize: false
-}),
-```
+You were trying to get a CSRF response from Auth.js (eg.: by calling a `/csrf` endpoint), but in this setup, CSRF protection via Auth.js was turned off. This is likely if you are not directly using `@auth/core` but a framework library (like `@auth/sveltekit`) that already has CSRF protection built-in. You likely won't need the CSRF response.

packages/core/src/lib/assert.ts

@@ -45,7 +45,7 @@ export function assertConfig(
   const { url } = request
   const warnings: WarningCode[] = []
 
-  if (!warned && options.debug) warnings.push("debug_enabled")
+  if (!warned && options.debug) warnings.push("debug-enabled")
 
   if (!options.trustHost) {
     return new UntrustedHost(`Host must be trusted. URL was: ${request.url}`)

packages/core/src/lib/index.ts

@@ -52,12 +52,22 @@ export async function AuthInternal<
         // eslint-disable-next-line @typescript-eslint/no-unnecessary-type-assertion
         return { ...session, cookies } as any
       }
-      case "csrf":
+      case "csrf": {
+        if (csrfDisabled) {
+          options.logger.warn("csrf-disabled")
+          cookies.push({
+            name: options.cookies.csrfToken.name,
+            value: "",
+            options: { ...options.cookies.csrfToken.options, maxAge: 0 },
+          })
+          return { status: 404, cookies }
+        }
         return {
           headers: { "Content-Type": "application/json" },
           body: { csrfToken: options.csrfToken } as any,
           cookies,
         }
+      }
       case "signin":
         if (pages.signIn) {
           let signinUrl = `${pages.signIn}${

packages/core/src/lib/utils/logger.ts

@@ -1,6 +1,6 @@
 import { AuthError } from "../../errors.js"
 
-export type WarningCode = "debug_enabled"
+export type WarningCode = "debug-enabled" | "csrf-disabled"
 
 /**
  * Override any of the methods, and the rest will use the default logger.
@@ -38,7 +38,7 @@ export const logger: LoggerInstance = {
     }
   },
   warn(code) {
-    const url = `https://errors.authjs.dev#${code}`
+    const url = `https://warnings.authjs.dev#${code}`
     console.warn(`${yellow}[auth][warn][${code}]${reset}`, `Read more: ${url}`)
   },
   debug(message, metadata) {