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 by reference 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);
$r->add_config($lines, $override, $path);
$r->add_config($lines, $override, $path, $override_opts);
Configuration directives are processed as if given in a <Location>
block.
- 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
(Apache2::Const override constant
) -
Which allow-override bits are set
Default value is:
Apache2::Const::OR_AUTHCFG
- opt arg3:
$path
( string ) -
Set the
Apache2::CmdParms object
path
component. This is the path of the<Location>
block. Some directives need this, for exampleProxyPassReverse
.If an empty string is passed a
NULL
pointer is passed further at C-level. This is necessary to make something like this work:$r->add_config( [ '<Directory />', 'AllowOverride Options AuthConfig', '</Directory>', ], ~0, '' );
Note:
AllowOverride
is valid only in directory context.Caution: Some directives need a non-empty path otherwise they cause segfaults. Thus, use the empty path with caution.
Default value is:
/
- opt arg4:
$override_opts
(Apache2::Const options constant
) -
Apache limits the applicable directives in certain situations with
AllowOverride
. With Apache 2.2 comes the possibility to enable or disable single options, for exampleAllowOverride AuthConfig Options=ExecCGI,Indexes
Internally, this directive is parsed into 2 bit fields that are represented by the
$override
and$override_opts
parameters toadd_config
. The above example is parsed into an$override
with 2 bits set, one forAuthConfig
the other forOptions
and an$override_opts
with 2 bits set for ExecCGI and Indexes.When applying other directives, for example
AuthType
orOptions
the appropriate bits in$override
must be set. For theOptions
directive additionally$override_opts
bits must be set.The
$override
and$override_opts
parameters toadd_config
are valid while applying$lines
.$override_opts
is new in Apache 2.2. The mod_perl implementation for Apache 2.0 lets you pass the parameter but ignores it.Default for
$override_opts
is:Apache2::Const::OPT_UNSET
|Apache2::Const::OPT_ALL
|Apache2::Const::OPT_INCNOEXEC
|Apache2::Const::OPT_SYM_OWNER
|Apache2::Const::OPT_MULTI
That means, all options are allowed.
- ret: no return value
- since: 2.0.00,
$path
and$override_opts
since 2.0.3
See also: $s->add_config
For example:
use Apache2::RequestUtil ();
use Apache2::Access ();
$r->add_config(['require valid-user']);
# this regards the current AllowOverride setting
$r->add_config(['AuthName secret',
'AuthType Basic',
'Options ExecCGI'],
$r->allow_override, $path, $r->allow_override_opts);
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.
- 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 createdApache2::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
# to share variables by value and not reference, $val should be a lexical.
$old_val = $r->pnotes($key => $val);
$val = $r->pnotes($key);
$hash_ref = $r->pnotes();
Note: sharing variables really means it. The variable is not copied. Only its reference count is incremented. If it is changed after being put in pnotes that change also affects the stored value. The following example illustrates the effect:
my $v=1; my $v=1;
$r->pnotes( 'v'=>$v ); $r->pnotes->{v}=$v;
$v++; $v++;
my $x=$r->pnotes('v'); my $x=$r->pnotes->{v};
In both cases $x
is 2
not 1
. See also Apache2::SafePnotes
on CPAN.
There has been a lot of discussion advocating for pnotes sharing variables by value and not reference. Sharing by reference can create 'spooky action at a distance' effects when the sharing is assumed to share a copy of the value. Tim Bunce offers the following summary and suggestion for sharing by value.
What's wrong with this code:
sub foo {
my ($r, $status, $why) = @_;
$r->pnotes('foo', ($why) ? "$status:$why" : $status);
return;
}
Nothing, except it doesn't work as expected due to this pnotes bug: If the same code is called in a sub-request then the pnote of $r->prev is magically updated at a distance to the same value!
Try explain why that is to anyone not deeply familar with perl internals!
The fix is to avoid pnotes taking a ref to the invisible op_targ embededed in the code by passing a simple lexical variable as the actual argument. That can be done in-line like this:
sub mark_as_internally_redirected {
my ($r, $status, $why) = @_;
$r->pnotes('foo', my $tmp = (($why) ? "$status:$why" : $status));
return;
}
- 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, otherwiseundef
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
andadd_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 wellrequire()
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
andAPR::Status::is_ENOENT
. - since: 2.0.00
Note that if you assign to $r->filename
you need to update its stat record.
See Also
Copyright
mod_perl 2.0 and its core modules are copyrighted under The Apache Software License, Version 2.0.