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Version: 3.13.0


The Response() constructor creates a new Response object.


new Response()
new Response(body)
new Response(body, options)


  • body optional

  • options optional

    • : An options object containing any custom settings that you want to apply to the response, or an empty object (which is the default value). The possible options are:

      • status
        • : The status code for the response, e.g., 200.
      • statusText
        • : The status message associated with the status code, e.g., OK.
      • headers
        • : Any headers you want to add to your response, contained within a Headers object or object literal of String key/value pairs.
      • manualFramingHeaders: boolean optional Fastly-specific
        • : The default value is false, which means that the framing headers are automatically created based on the message body. In "automatic" mode, a Content-Length is used when the size of the body can be determined before it is sent. Responses sent in streaming mode, where headers are sent immediately but the content of the body is streamed later, will receive a Transfer-Encoding: chunked to accommodate the dynamic generation of the body. In "manual" mode, any Content-Length or Transfer-Encoding headers will be honored. You must ensure that those headers have correct values permitted by the HTTP/1.1 specification. If the provided headers are not permitted by the specification, the headers will revert to "automatic" mode and a diagnostic message will be logged about what was wrong. If a Content-Length is permitted by the specification, but the value does not match the size of the actual body, the body will either be truncated (if it is too long), or the connection will be hung up early (if it is too short).