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libapache2-mod-perl2-2.0.11::docs::api::Apache2::Response(3pm) User Contributed Perl Documentation libapache2-mod-perl2-2.0.11::docs::api::Apache2::Response(3pm)


Apache2::Response - Perl API for Apache HTTP request response methods


  use Apache2::Response ();
  $r->custom_response(Apache2::Const::FORBIDDEN, "No Entry today");
  $etag = $r->make_etag($force_weak);
  $status = $r->meets_conditions();
  $mtime_rat = $r->rationalize_mtime($mtime);
  $ret = $r->set_keepalive();


"Apache2::Response" provides the Apache request object utilities API for dealing with HTTP response generation process.


"Apache2::Response" provides the following functions and/or methods:


Install a custom response handler for a given status

  $r->custom_response($status, $string);
The current request
The status for which the custom response should be used (e.g. "Apache2::Const::AUTH_REQUIRED")
The custom response to use. This can be a static string, or a URL, full or just the uri path (/foo/bar.txt).

"custom_response()" doesn't alter the response code, but is used to replace the standard response body. For example, here is how to change the response body for the access handler failure:

  package MyApache2::MyShop;
  use Apache2::Response ();
  use Apache2::Const -compile => qw(FORBIDDEN OK);
  sub access {
      my $r = shift;
      if (MyApache2::MyShop::tired_squirrels()) {
              "It's siesta time, please try later");
          return Apache2::Const::FORBIDDEN;
      return Apache2::Const::OK;
  # httpd.conf
  PerlModule MyApache2::MyShop
  <Location /TestAPI__custom_response>
      AuthName dummy
      AuthType none
      PerlAccessHandler   MyApache2::MyShop::access
      PerlResponseHandler MyApache2::MyShop::response

When squirrels can't run any more, the handler will return 403, with the custom message:

  It's siesta time, please try later


Construct an entity tag from the resource information. If it's a real file, build in some of the file characteristics.

  $etag = $r->make_etag($force_weak);
The current request
Force the entity tag to be weak - it could be modified again in as short an interval.
The entity tag


Implements condition "GET" rules for HTTP/1.1 specification. This function inspects the client headers and determines if the response fulfills the specified requirements.

  $status = $r->meets_conditions();
The current request
"Apache2::Const::OK" if the response fulfills the condition GET rules. Otherwise some other status code (which should be returned to Apache).

Refer to the Generating Correct HTTP Headers document for an indepth discussion of this method.


Return the latest rational time from a request/mtime pair.

  $mtime_rat = $r->rationalize_mtime($mtime);
The current request
The last modified time
the latest rational time from a request/mtime pair. Mtime is returned unless it's in the future, in which case we return the current time.


Parse the header

headers and optionally a response body

This method is really for back-compatibility with mod_perl 1.0. It's very inefficient to send headers this way, because of the parsing overhead.

If there is a response body following the headers it'll be handled too (as if it was sent via "print()").

Notice that if only HTTP headers are included they won't be sent until some body is sent (again the "send" part is retained from the mod_perl 1.0 method).


Set the content length for this request.

The current request
The new content length


Set the E-tag outgoing header



Set the keepalive status for this request

  $ret = $r->set_keepalive();
The current request
true if keepalive can be set, false otherwise

It's called by "ap_http_header_filter()". For the complete complicated logic implemented by this method see httpd-2.0/server/http_protocol.c.


sets the "Last-Modified" response header field to the value of the mtime field in the request structure -- rationalized to keep it from being in the future.

if the $mtime argument is passed, $r->update_mtime will be first run with that argument.


Set the "$r->mtime" field to the specified value if it's later than what's already there.

The current request

See also: $r->set_last_modified.

Unsupported API

"Apache2::Response" also provides auto-generated Perl interface for a few other methods which aren't tested at the moment and therefore their API is a subject to change. These methods will be finalized later as a need arises. If you want to rely on any of the following methods please contact the the mod_perl development mailing list so we can help each other take the steps necessary to shift the method to an officially supported API.


Send an "error" response back to client. It is used for any response that can be generated by the server from the request record. This includes all 204 (no content), 3xx (redirect), 4xx (client error), and 5xx (server error) messages that have not been redirected to another handler via the ErrorDocument feature.

The current request
the error status in case we get an error in the process of trying to deal with an "ErrorDocument" to handle some other error. In that case, we print the default report for the first thing that went wrong, and more briefly report on the problem with the "ErrorDocument".

META: it's really an internal Apache method, I'm not quite sure how can it be used externally.


META: Autogenerated - needs to be reviewed/completed

Send an MMAP'ed file to the client

  $ret = $r->send_mmap($mm, $offset, $length);
The current request
The MMAP'ed file to send
The offset into the MMAP to start sending
The amount of data to send
The number of bytes sent

META: requires a working APR::Mmap, which is not supported at the moment.

See Also

mod_perl 2.0 documentation.


mod_perl 2.0 and its core modules are copyrighted under The Apache Software License, Version 2.0.


The mod_perl development team and numerous contributors.

2021-02-22 perl v5.32.1