Method allowedMethods

router.ts:775–821

Middleware that handles requests for HTTP methods registered with the * router. If none of the routes handle a method, then "not allowed" logic * will be used. If a method is supported by some routes, but not the * particular matched router, then "not implemented" will be returned. *

(
    options: RouterAllowedMethodsOptions = {},
  )

   * options, of which the value will be returned will be thrown instead of the
   * HTTP error. */
  allowedMethods(
    options: RouterAllowedMethodsOptions = {},
  ): Middleware {
    const implemented = this.#methods;

    const allowedMethods: Middleware = async (context, next) => {
      const ctx = context as RouterContext<string>;
      await next();
      if (!ctx.response.status || ctx.response.status === Status.NotFound) {
        assert(ctx.matched);
        const allowed = new Set<HTTPMethods>();
        for (const route of ctx.matched) {
          for (const method of route.methods) {
            allowed.add(method);
          }
        }

        const allowedStr = [...allowed].join(", ");
        if (!implemented.includes(ctx.request.method)) {
          if (options.throw) {
            throw options.notImplemented
              ? options.notImplemented()
              : new errors.NotImplemented();
          } else {
            ctx.response.status = Status.NotImplemented;
            ctx.response.headers.set("Allow", allowedStr);
          }
        } else if (allowed.size) {
          if (ctx.request.method === "OPTIONS") {
            ctx.response.status = Status.OK;
            ctx.response.headers.set("Allow", allowedStr);
          } else if (!allowed.has(ctx.request.method)) {
            if (options.throw) {
              throw options.methodNotAllowed
                ? options.methodNotAllowed()
                : new errors.MethodNotAllowed();
            } else {
              ctx.response.status = Status.MethodNotAllowed;
              ctx.response.headers.set("Allow", allowedStr);
            }
          }
        }
      }
    };

    return allowedMethods;
  }

  /** Register named middleware for the specified routes when the `DELETE`,
   *  method is requested. */