Document serializeQueryArgs option

Author: markerikson

docs/rtk-query/api/createApi.mdx

@@ -490,12 +490,20 @@ See also [Invalidating cache data](../usage/automated-refetching.mdx#invalidatin
 
 _(optional, only for query endpoints)_
 
-Overrides the api-wide definition of `keepUnusedDataFor` for this endpoint only.
+Overrides the api-wide definition of `keepUnusedDataFor` for this endpoint only.a
 
 [summary](docblock://query/createApi.ts?token=CreateApiOptions.keepUnusedDataFor)
 
 [examples](docblock://query/createApi.ts?token=CreateApiOptions.keepUnusedDataFor)
 
+### `serializeQueryArgs`
+
+_(optional, only for query endpoints)_
+
+[summary](docblock://query/endpointDefinitions.ts?token=QueryExtraOptions.serializeQueryArgs)
+
+[examples](docblock://query/endpointDefinitions.ts?token=QueryExtraOptions.serializeQueryArgs)
+
 ### `onQueryStarted`
 
 _(optional)_

packages/toolkit/src/query/endpointDefinitions.ts

@@ -318,7 +318,56 @@ export interface QueryExtraOptions<
    */
   invalidatesTags?: never
 
-  serializeQueryArgs?: SerializeQueryArgs<any>
+  /**
+   * Can be provided to return a custom cache key string based on the provided arguments.
+   *
+   * This is primarily intended for cases where a non-serializable value is passed as part of the query arg object and should be excluded from the cache key.  It may also be used for cases where an endpoint should only have a single cache entry, such as an infinite loading / pagination implementation.
+   *
+   * @example
+   *
+   * ```ts
+   * // codeblock-meta title="serializeQueryArgs : exclude value"
+   *
+   * import { createApi, fetchBaseQuery, defaultSerializeQueryArgs } from '@reduxjs/toolkit/query/react'
+   * interface Post {
+   *   id: number
+   *   name: string
+   * }
+   *
+   * interface MyApiClient {
+   *   fetchPost: (id: string) => Promise<Post>
+   * }
+   *
+   * createApi({
+   *  baseQuery: fetchBaseQuery({ baseUrl: '/' }),
+   *  tagTypes: ['Posts'],
+   *  endpoints: (build) => ({
+   *    // Example: an endpoint with an API client passed in as an argument,
+   *    // but only the item ID should be used as the cache key
+   *    getPost: build.query<Post, { id: string; client: MyApiClient }>({
+   *      queryFn: async ({ id, client }) => {
+   *        const post = await client.fetchPost(id)
+   *        return { data: post }
+   *      },
+   *      // highlight-start
+   *      serializeQueryArgs: ({ queryArgs, endpointDefinition, endpointName }) => {
+   *        const { id } = queryArgs
+   *        // You can use `defaultSerializeQueryArgs` to do the work:
+   *        return defaultSerializeQueryArgs({
+   *          endpointName,
+   *          queryArgs: { id },
+   *          endpointDefinition
+   *        })
+   *        // Or alternately, create a string yourself:
+   *        // return `getPost(${id})`
+   *      },
+   *      // highlight-end
+   *    }),
+   *  }),
+   *})
+   * ```
+   */
+  serializeQueryArgs?: SerializeQueryArgs<QueryArg>
 
   /**
    * Can be provided to merge the current cache value into the new cache value.