docs::api::Apache2::RequestUtil

Section: User Contributed Perl Documentation (3)
Updated: 2005-10-20
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NAME

Apache2::RequestUtil - Perl API for Apache request record utils  

Synopsis

  use Apache2::RequestUtil ();

  # add httpd config dynamically
  $r->add_config(['require valid-user']);

  # dump the request object as a string
  print $r->as_string();

  # default content_type
  $content_type = $r->default_type();

  # get PerlSetVar/PerlAddVar values
  @values = $r->dir_config->get($key);

  # get server docroot
  $docroot = $r->document_root();

  # set server docroot
  $r->document_root($new_root);

  # what are the registered perl handlers for a given phase
  my @handlers = @{ $r->get_handlers('PerlResponseHandler') || [] };

  # push a new handler for a given phase
  $r->push_handlers(PerlCleanupHandler => \&handler);

  # set handlers for a given phase (resetting previous values)
  $r->set_handlers(PerlCleanupHandler => []);

  # what's the request body limit
  $limit = $r->get_limit_req_body();

  # server and port names
  $server = $r->get_server_name();
  $port   = $r->get_server_port();

  # what string Apache is going to send for a given status code
  $status_line = Apache2::RequestUtil::get_status_line(404);

  # are we in the main request?
  $is_initial = $r->is_initial_req();

  # directory level PerlOptions flags lookup
  $r->subprocess_env unless $r->is_perl_option_enabled('SetupEnv');

  # current <Location> value
  $location = $r->location();

  # merge a <Location> container in a request object
  $r->location_merge($location);

  # create a new Apache2::RequestRec object
  $r = Apache2::RequestRec->new($c);

  # tell the client not to cache the response
  $r->no_cache($boolean);

  # share perl objects like $r->notes
  $r->pnotes($key => [$obj1, $obj2]);

  # get HTML signature
  $sig = $r->psignature($prefix);

  # get the global request object (requires PerlOptions +GlobalRequest)
  $r = Apache2::RequestUtil->request;

  # insert auth credentials into the request as if the client did that
  $r->set_basic_credentials($username, $password);

  # slurp the contents of $r->filename
  my $content = ${ $r->slurp_filename() };

  # terminate the current child after this request
  $r->child_terminate();

 

Description

"Apache2::RequestUtil" provides the Apache request object utilities API.  

API

 

add_config

Dynamically add Apache configuration at request processing runtime:

  $r->add_config($lines);
  $r->add_config($lines, $override);

obj: $r ( Apache2::RequestRec object )
arg1: $lines (ARRAY ref)
An ARRAY reference containing configuration lines per element, without the new line terminators.
opt arg2: $override ( APR::Const status constant )
Which allow-override bits are set

Default value is: "Apache2::Const::OR_AUTHCFG"

ret: no return value
since: 2.0.00

See also: "$s->add_config"

For example:

  use Apache2::ServerUtil ();
  $r->add_config(['require valid-user']);

 

as_string

Dump the request object as a string

  $dump = $r->as_string();

obj: $r ( Apache2::RequestRec object )
ret: $dump ( string )
since: 2.0.00

Dumps various request and response headers (mainly useful for debugging)  

child_terminate

Terminate the current worker process as soon as the current request is over

  $r->child_terminate();

obj: $r ( Apache2::RequestRec object )
ret: no return value
since: 2.0.00

This method is not supported in threaded MPMs  

default_type

Retrieve the value of the DefaultType directive for the current request. If not set "text/plain" is returned.

  $content_type = $r->default_type();

obj: $r ( Apache2::RequestRec object )
The current request
ret: $content_type ( string )
The default type
since: 2.0.00
 

dir_config

"$r->dir_config()" provides an interface for the per-directory variable specified by the "PerlSetVar" and "PerlAddVar" directives, and also can be manipulated via the "APR::Table" methods.

  $table  = $r->dir_config();
  $value  = $r->dir_config($key);
  @values = $r->dir_config->get($key);
  $r->dir_config($key, $val);

obj: $r ( Apache2::RequestRec object )
opt arg2: $key ( string )
Key string
opt arg3: $val ( string )
Value string
ret: ...
Depends on the passed arguments, see further discussion
since: 2.0.00

The keys are case-insensitive.

  $apr_table = $r->dir_config();

dir_config() called in a scalar context without the $key argument returns a HASH reference blessed into the "APR::Table" class. This object can be manipulated via the "APR::Table" methods. For available methods see the "APR::Table" manpage.

  $value = $r->dir_config($key);

If the $key argument is passed in the scalar context only a single value will be returned. Since the table preserves the insertion order, if there is more than one value for the same key, the oldest value assosiated with the desired key is returned. Calling in the scalar context is also much faster, as it'll stop searching the table as soon as the first match happens.

  @values = $r->dir_config->get($key);

To receive a list of values you must use "get()" method from the "APR::Table" class.

  $r->dir_config($key => $val);

If the $key and the $val arguments are used, the set() operation will happen: all existing values associated with the key $key (and the key itself) will be deleted and $value will be placed instead.

  $r->dir_config($key => undef);

If $val is undef the unset() operation will happen: all existing values associated with the key $key (and the key itself) will be deleted.  

document_root

Retrieve the document root for this server

  $docroot = $r->document_root();
  $docroot = $r->document_root($new_root);

obj: $r ( Apache2::RequestRec object )
The current request
opt arg1: $new_root
Sets the document root to a new value only for the duration of the current request.

Note the limited functionality under threaded MPMs.

ret: $docroot ( string )
The document root
since: 2.0.00
 

get_handlers

Returns a reference to a list of handlers enabled for a given phase.

  $handlers_list = $r->get_handlers($hook_name);

obj: $r ( Apache2::RequestRec object )
arg1: $hook_name ( string )
a string representing the phase to handle (e.g. "PerlLogHandler")
ret: $handlers_list (ref to an ARRAY of CODE refs)
a list of handler subroutines CODE references
since: 2.0.00

See also: "$s->add_config"

For example:

A list of handlers configured to run at the response phase:

  my @handlers = @{ $r->get_handlers('PerlResponseHandler') || [] };

 

get_limit_req_body

Return the limit on bytes in request msg body

  $limit = $r->get_limit_req_body();

obj: $r ( Apache2::RequestRec object )
The current request
ret: $limit (integer)
the maximum number of bytes in the request msg body
since: 2.0.00
 

get_server_name

Get the current request's server name

  $server = $r->get_server_name();

obj: $r ( Apache2::RequestRec object )
The current request
ret: $server ( string )
the server name
since: 2.0.00

For example, consruct a hostport string:

  use Apache2::RequestUtil ();
  my $hostport = join ':', $r->get_server_name, $r->get_server_port;

 

get_server_port

Get the current server port

  $port = $r->get_server_port();

obj: $r ( Apache2::RequestRec object )
The current request
ret: $port ( integer )
The server's port number
since: 2.0.00

For example, consruct a hostport string:

  use Apache2::RequestUtil ();
  my $hostport = join ':', $r->get_server_name, $r->get_server_port;

 

get_status_line

Return the "Status-Line" for a given status code (excluding the HTTP-Version field).

  $status_line = Apache2::RequestUtil::get_status_line($status);

arg1: $status (integer)
The HTTP status code
ret: $status_line ( string )
The Status-Line

If an invalid or unknown status code is passed, ""500 Internal Server Error"" will be returned.

since: 2.0.00

For example:

  use Apache2::RequestUtil ();
  print Apache2::RequestUtil::get_status_line(400);

will print:

  400 Bad Request

 

is_initial_req

Determine whether the current request is the main request or a sub-request

  $is_initial = $r->is_initial_req();

obj: $r ( Apache2::RequestRec object )
A request or a sub-request object
ret: $is_initial ( boolean )
If true --- it's the main request, otherwise it's a sub-request
since: 2.0.00
 

is_perl_option_enabled

check whether a directory level "PerlOptions" flag is enabled or not.

  $result = $r->is_perl_option_enabled($flag);

obj: $r ( Apache2::RequestRec object )
arg1: $flag ( string )
ret: $result ( boolean )
since: 2.0.00

For example to check whether the "SetupEnv" option is enabled for the current request (which can be disabled with "PerlOptions -SetupEnv") and populate the environment variables table if disabled:

  $r->subprocess_env unless $r->is_perl_option_enabled('SetupEnv');

See also: PerlOptions and the equivalent function for server level PerlOptions flags.  

location

Get the path of the <Location> section from which the current "Perl*Handler" is being called.

  $location = $r->location();

obj: $r ( Apache2::RequestRec object )
ret: $location ( string )
since: 2.0.00
 

location_merge

Merge a given "<Location<" container into the current request object:

  $ret = $r->location_merge($location);

obj: $r ( Apache2::RequestRec object )
arg1: $location ( string )
The argument in a "<Location<" section. For example to merge a container:

  <Location /foo>
      ...
  </Location>

that argument will be /foo

ret: $ret ( boolean )
a true value if the merge was successful (i.e. the request $location match was found), otherwise false.
since: 2.0.00

Useful for insertion of a configuration section into a custom "Apache2::RequestRec" object, created via the "Apache2::RequestRec->new()" method. See for example the Command Server protocol example.  

new

Create a new "Apache2::RequestRec" object.

  $r = Apache2::RequestRec->new($c);
  $r = Apache2::RequestRec->new($c, $pool);

obj: Apache2::RequestRec ( Apache2::RequestRec class name )
arg1: $c (Apache2::Connection object)
opt arg2: $pool
If no $pool argument is passed, "$c->pool" is used. That means that the created "Apache2::RequestRec" object will be valid as long as the connection object is valid.
ret: $r ( Apache2::RequestRec object )
since: 2.0.00

It's possible to reuse the HTTP framework features outside the familiar HTTP request cycle. It's possible to write your own full or partial HTTP implementation without needing a running Apache server. You will need the "Apache2::RequestRec" object in order to be able to reuse the rich functionality supplied via this object.

See for example the Command Server protocol example which reuses HTTP AAA model under non-HTTP protocol.  

no_cache

Add/remove cache control headers:

  $prev_no_cache = $r->no_cache($boolean);

obj: $r ( Apache2::RequestRec object )
arg1: $boolean ( boolean )
A true value sets the "no_cache" request record member to a true value and inserts:

  Pragma: no-cache
  Cache-control: no-cache

into the response headers, indicating that the data being returned is volatile and the client should not cache it.

A false value unsets the "no_cache" request record member and the mentioned headers if they were previously set.

ret: $prev_no_cache ( boolean )
Should you care, the "no_cache" request record member value prior to the change is returned.
since: 2.0.00

This method should be invoked before any response data has been sent out.  

pnotes

Share Perl variables between Perl HTTP handlers

  $old_val  = $r->pnotes($key => $val);
  $val      = $r->pnotes($key);
  $hash_ref = $r->pnotes();

obj: $r ( Apache2::RequestRec object )
opt arg1: $key ( string )
A key value
opt arg2: $val ( SCALAR )
Any scalar value (e.g. a reference to an array)
ret: (3 different possible values)
if both, $key and $val are passed the previous value for $key is returned if such existed, otherwise "undef" is returned.

if only $key is passed, the current value for the given key is returned.

if no arguments are passed, a hash reference is returned, which can then be directly accessed without going through the "pnotes()" interface.

since: 2.0.00

This method provides functionality similar to ("Apache2::RequestRec::notes"), but values can be any Perl variables. That also means that it can be used only between Perl modules.

The values get reset automatically at the end of each HTTP request.

Examples:

Set a key/value pair:

  $r->pnotes(foo => [1..5]);

Get the value:

  $val = $r->pnotes("foo");

$val now contains an array ref containing 5 elements (1..5).

Now change the existing value:

  $old_val = $r->pnotes(foo => ['a'..'c']);
  $val = $r->pnotes("foo");

$old_val now contains an array ref with 5 elements (1..5) and $val contains an array ref with 3 elements 'a', 'b', 'c'.

Alternatively you can access the hash reference with all pnotes values:

  $pnotes = $r->pnotes;

Now we can read what's in there for the key foo:

  $val = $pnotes->{foo};

and as before $val still gives us an array ref with 3 elements 'a', 'b', 'c'.

Now we can add elements to it:

  push @{ $pnotes{foo} }, 'd'..'f';

and we can try to retrieve them using the hash and non-hash API:

  $val1 = $pnotes{foo};
  $val2 = $r->pnotes("foo");

Both $val1 and $val2 contain an array ref with 6 elements (letters 'a' to 'f').

Finally to reset an entry you could just assign "undef" as a value:

  $r->pnotes(foo => undef);

but the entry for the key foo still remains with the value "undef". If you really want to completely remove it, use the hash interface:

  delete $r->pnotes->{foo};

 

psignature

Get HTML describing the address and (optionally) admin of the server.

  $sig = $r->psignature($prefix);

obj: $r ( Apache2::RequestRec )
arg1: $prefix ( string )
Text which is prepended to the return value
ret: $sig ( string )
HTML text describing the server. Note that depending on the value of the "ServerSignature" directive, the function may return the address, including the admin information or nothing at all.
since: 2.0.00
 

request

Get/set the ( "Apache2::RequestRec object" ) object for the current request.

  $r = Apache2::RequestUtil->request;
       Apache2::RequestUtil->request($new_r);

obj: Apache2 (class name)
The Apache class name
opt arg1: $new_r ( Apache2::RequestRec object )
ret: $r ( Apache2::RequestRec object )
since: 2.0.00

The get-able part of this method is only available if "PerlOptions +GlobalRequest" is in effect or if "Apache2->request($new_r)" was called earlier. So instead of setting "PerlOptions +GlobalRequest", one can set the global request from within the handler.  

push_handlers

Add one or more handlers to a list of handlers to be called for a given phase.

  $ok = $r->push_handlers($hook_name => \&handler);
  $ok = $r->push_handlers($hook_name => ['Foo::Bar::handler', \&handler2]);

obj: $r ( Apache2::RequestRec object )
arg1: $hook_name ( string )
the phase to add the handlers to
arg2: $handlers ( CODE ref or SUB name or an ARRAY ref )
a single handler CODE reference or just a name of the subroutine (fully qualified unless defined in the current package).

if more than one passed, use a reference to an array of CODE refs and/or subroutine names.

ret: $ok ( boolean )
returns a true value on success, otherwise a false value
since: 2.0.00
See also: "$s->add_config"

Note that to push input/output filters you have to use "Apache2::Filter" methods: "add_input_filter" and "add_output_filter".

Examples:

A single handler:

  $r->push_handlers(PerlResponseHandler => \&handler);

Multiple handlers:

  $r->push_handlers(PerlFixupHandler => ['Foo::Bar::handler', \&handler2]);

Anonymous functions:

  $r->push_handlers(PerlLogHandler => sub { return Apache2::Const::OK });

 

set_basic_credentials

Populate the incoming request headers table ("headers_in") with authentication headers for Basic Authorization as if the client has submitted those in first place:

  $r->set_basic_credentials($username, $password);

obj: $r ( Apache2::RequestRec object )
arg1: $username ( string )
arg2: $password ( string )
ret: no return value
since: 2.0.00

See for example the Command Server protocol example which reuses HTTP AAA model under non-HTTP protocol.  

set_handlers

Set a list of handlers to be called for a given phase. Any previously set handlers are forgotten.

  $ok = $r->set_handlers($hook_name => \&handler);
  $ok = $r->set_handlers($hook_name => ['Foo::Bar::handler', \&handler2]);
  $ok = $r->set_handlers($hook_name => []);
  $ok = $r->set_handlers($hook_name => undef);

obj: $r ( Apache2::RequestRec object )
arg1: $hook_name ( string )
the phase to set the handlers in
arg2: $handlers (CODE ref or SUB name or an ARRAY ref)
a reference to a single handler CODE reference or just a name of the subroutine (fully qualified unless defined in the current package).

if more than one passed, use a reference to an array of CODE refs and/or subroutine names.

if the argument is "undef" or "[]" the list of handlers is reset to zero.

ret: $ok ( boolean )
returns a true value on success, otherwise a false value
since: 2.0.00

See also: "$s->add_config"

Examples:

A single handler:

  $r->set_handlers(PerlResponseHandler => \&handler);

Multiple handlers:

  $r->set_handlers(PerlFixupHandler => ['Foo::Bar::handler', \&handler2]);

Anonymous functions:

  $r->set_handlers(PerlLogHandler => sub { return Apache2::Const::OK });

Reset any previously set handlers:

  $r->set_handlers(PerlCleanupHandler => []);

or

  $r->set_handlers(PerlCleanupHandler => undef);

 

slurp_filename

Slurp the contents of "$r->filename":

  $content_ref = $r->slurp_filename($tainted);

obj: $r ( Apache2::RequestRec object )
arg1: $tainted (number)
If the server is run under the tainting mode ("-T") which we hope you do, by default the returned data is tainted. If an optional $tainted flag is set to zero, the data will be marked as non-tainted.

Do not set this flag to zero unless you know what you are doing, you may create a security hole in your program if you do. For more information see the perlsec manpage.

If you wonder why this option is available, it is used internally by the "ModPerl::Registry" handler and friends, because the CGI scripts that it reads are considered safe (you could just as well "require()" them).

ret: $content_ref ( SCALAR ref )
A reference to a string with the contents
excpt: APR::Error
Possible error codes could be: "APR::Const::EACCES" (permission problems), "APR::Const::ENOENT" (file not found), and others. For checking such error codes, see the documentation for, for example, "APR::Status::is_EACCES" and "APR::Status::is_ENOENT".
since: 2.0.00

Note that if you assign to "$r->filename" you need to update its stat record.  

See Also

mod_perl 2.0 documentation.  

Copyright

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

Authors

The mod_perl development team and numerous contributors.


 

Index

NAME
Synopsis
Description
API
add_config
as_string
child_terminate
default_type
dir_config
document_root
get_handlers
get_limit_req_body
get_server_name
get_server_port
get_status_line
is_initial_req
is_perl_option_enabled
location
location_merge
new
no_cache
pnotes
psignature
request
push_handlers
set_basic_credentials
set_handlers
slurp_filename
See Also
Copyright
Authors

linux.jgfs.net manual pages