Function koaGuard

packages/core/src/middleware/koa-guard.ts:130–250

({
  query,
  body,
  params,
  response,
  status,
  files,
}: GuardConfig<
  GuardQueryT,
  GuardBodyT,
  GuardParametersT,
  GuardResponseT,
  GuardFilesT
>)

 * Note: A context-aware console log is required to be present in the context (i.e. `ctx.console`).
 */
export default function koaGuard<
  StateT,
  ContextT extends IRouterParamContext,
  GuardQueryT = undefined,
  GuardBodyT = undefined,
  GuardParametersT = undefined,
  GuardResponseT = unknown,
  GuardFilesT = undefined,
>({
  query,
  body,
  params,
  response,
  status,
  files,
}: GuardConfig<
  GuardQueryT,
  GuardBodyT,
  GuardParametersT,
  GuardResponseT,
  GuardFilesT
>): MiddlewareType<
  StateT,
  WithGuardedRequestContext<ContextT, GuardQueryT, GuardBodyT, GuardParametersT, GuardFilesT>,
  GuardResponseT
> {
  const guard: MiddlewareType<
    StateT,
    WithGuardedRequestContext<ContextT, GuardQueryT, GuardBodyT, GuardParametersT, GuardFilesT>,
    GuardResponseT
  > = async (ctx, next) => {
    // eslint-disable-next-line @typescript-eslint/consistent-type-assertions, no-restricted-syntax
    ctx.guard = {
      query: tryParse('query', query, ctx.request.query),
      body: tryParse('body', body, ctx.request.body ?? {}), // Fallback to empty object since it's the original behavior of koa-body@5
      params: tryParse('params', params, ctx.params),
      files: tryParse('files', files, ctx.request.files),
    } as GuardedRequest<GuardQueryT, GuardBodyT, GuardParametersT, GuardFilesT>; // Have to do this since it's too complicated for TS

    return next();
  };

  const guardMiddleware: WithGuardConfig<
    MiddlewareType<
      StateT,
      WithGuardedRequestContext<ContextT, GuardQueryT, GuardBodyT, GuardParametersT, GuardFilesT>,
      GuardResponseT
    >
  > = async function (ctx, next) {
    const consoleLog = getConsoleLogFromContext(ctx);

    /**
     * Assert the status code matches the value(s) in the config. If the config does not
     * specify a status code, it will not assert anything.
     *
     * In production, it will log a warning if the status code does not match the value(s) in the
     * config for better user experience.
     *