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Type Guards

@opra/http exports four type guard functions for narrowing HTTP message types at runtime.

import {
  isHttpIncomingMessage,
  isHttpRequest,
  isHttpOutgoingMessage,
  isHttpResponse,
} from '@opra/http';

isHttpIncomingMessage​

isHttpIncomingMessage(v: any): v is http.IncomingMessage

Returns true if v is an instance of Node.js http.IncomingMessage. Use to check for the low-level request object before upgrading to HttpRequest.

isHttpRequest​

isHttpRequest(v: any): v is HttpRequest

Returns true if v passes isHttpIncomingMessage and additionally exposes header(), acceptsLanguages(), and readBody(). Use to distinguish a fully-featured HttpRequest from a bare http.IncomingMessage.

isHttpOutgoingMessage​

isHttpOutgoingMessage(v: any): v is http.OutgoingMessage

Returns true if v has a getHeaders() method and is a stream. Use to check for the low-level response object before upgrading to HttpResponse.

isHttpResponse​

isHttpResponse(v: any): v is HttpResponse

Returns true if v passes isHttpOutgoingMessage and additionally exposes clearCookie() and cookie(). Use to distinguish a fully-featured HttpResponse from a bare http.OutgoingMessage.