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Config(3pm) User Contributed Perl Documentation Config(3pm)

NAME

Embperl::Config - Embperl configuration and calling

Operating-Modes

Embperl can operate in one of four modes:

The mostly used way is to use Embperl together with mod_perl and Apache. This gives the best performance and the most possibilities.
When you want to run Embperl on a machine that doesn't have mod_perl, you can run Embperl also as normal CGI script. Due to the overhead of CGI, this mode is much slower. To get a better performance you should consider using Embperl together with FastCGI. (http://www.fastcgi.com).
You can use Embperl also on the command line. This is useful for generating static content out of dynamic pages and can sometime be helpful for testing.
If you have your own application and want to use Embperl's capbilities you can do so by calling Embperl::Execute. This allows you to build your own application logic and use Embperl possibilities for rendering content.

mod_perl

To use Embperl under mod_perl you must have installed Apache and mod_perl on your system. Then you add some directives to your httpd.conf to load Embperl and add "Embperl" as the "PerlHandler". The following directives will cause all file with extetion epl to be handled by Embperl:

    PerlModule Embperl
    AddType text/html .epl
    <Files *.epl>
    SetHandler  perl-script
    PerlHandler Embperl
    Options     ExecCGI
    </files>

Another possibility is to have all files under a special location processed by Embperl:

    PerlModule Embperl
    Alias /embperl /path/to/embperl/eg
    <Location /embperl/x>
    SetHandler  perl-script
    PerlHandler Embperl
    Options     ExecCGI
    </Location>

In this setup you should make sure that non Embperl files like images doesn't served from this directory.

For mod_perl 2.0 you need addtionaly to load the dynamic object library of Embperl. This is necessary so Embperl is loaded early enough to register the configuration directives with Apache. After installing, search underneath your Perl site directory for the library. On Unix it is mostly called Embperl.so on Windows it is called "Embperl.dll". Now add the following line to your httpd.conf before any of the Embperl configuration directives, but after mod_perl.so is loaded:

    LoadModule  embperl_module  /path/to/perl/site/lib/Embperl/Embperl.so

To use Embperl::Object you use the "Embperl::Object" as "PerlHandler":

    <Location /foo>
        Embperl_AppName     unique-name
        Embperl_Object_Base base.htm
        Embperl_UriMatch    "\.htm.?|\.epl$"
        SetHandler          perl-script
        PerlHandler         Embperl::Object 
        Options             ExecCGI
    </Location>

Addtionaly you can setup other parameters for Embperl::Object. If you do so inside a container (like "<Location", <Directory>, <Files>>) you need to set "Embperl_AppName" to a unique-name (the actual value doesn't matter). The "Embperl_UriMatch" makes sure that only files of the requested type are served by Embperl::Object, while all others are served by Apache as usual.

For more information see: "perldoc Embperl::Object".

Embperl accepts a lot of configuration directives to customize it's behaviour. See the next section for a description.

NOTE: If mod_perl is statically linked into Apache you can not use ClearModuleList in your httpd.conf

Preloading pages

To optimize memory usage you can preload your pages during the initialization. If you do so they will get loaded into the parent process and the memory will be shared by all child processes.

To let Embperl preload your files, you have to supply all the filename into the key preloadfiles of the hash %initparam, before you load Embperl.

Example:

  BEGIN 
    {
    $Embperl::initparam{preloadfiles} = 
        [
        '/path/to/foo.epl',
        '/path/to/bar.epl',
        { inputfile  => "/path/to/other.epl", input_escmode => 7 },
        ] ;
    }
  use Embperl ;

As you see for the third file, it is also possible to give a hashref and supply the same parameter like Execute accpets (see below).

NOTE: Preloading is not supported under Apache 1.3, when mod_perl is loaded as DSO. To use preloading under Apache 1.3 you need to compile mod_perl statically into Apache.

CGI/FastCGI

To use this mode you must copy embpcgi.pl to your cgi-bin directory. You can invoke it with the URL http://www.domain.xyz/cgi-bin/embpcgi.pl/url/of/your/document.

The /url/of/your/document will be passed to Embperl by the web server. Normal processing (aliasing, etc.) takes place before the URI makes it to PATH_TRANSLATED.

If you are running the Apache httpd, you can also define embpcgi.pl as a handler for a specific file extension or directory.

Example of Apache "httpd.conf":

    <Directory /path/to/your/html/docs>
    Action text/html /cgi-bin/embperl/embpcgi.pl
    </Directory>

NOTE: Via CGI Scripts it maybe possible to bypass some of the Apache setup. To avoid this use Embperl_Allow to restrict access to the files, which should be processed by Embperl.

For Embperl::Object you have to use epocgi.pl instead of embpcgi.pl.

You can also run Embperl with FastCGI, in this case use embpfastcgi.pl as cgi script. You must have FCGI.pm installed.

Offline

Run Embperl from the comannd line use embpexec.pl on unix and embpexec.bat on windows:

embpexec.pl [options] htmlfile [query_string]

embpexec.bat [options] htmlfile [query_string]

The full pathname of the source file which should be processed by Embperl.
Optional. Has the same meaning as the environment variable QUERY_STRING when invoked as a CGI script. That is, QUERY_STRING contains everything following the first "?" in a URL. <query_string> should be URL-encoded. The default is no query string.

Options:

Optional. Gives the filename to which the output is written. The default is stdout.
Optional. Gives the filename of the logfile. The default is /tmp/embperl.log on unix and \embperl.log on windows.
Optional. Specifies the level of debugging (what is written to the log file). The default is nothing. See "EMBPERL_DEBUG" for exact values.
See "EMBPERL_OPTIONS" for option values.
Defines the syntax of the source. See See "EMBPERL_SYNTAX"
Gives a value which is passed in the @param array to the executed page. Can be given multiple times.
Gives a name/value pair which is passed in the %fdat hash to the executed page. Can be given multiple times.

By calling Embperl::Execute (\%param)

"Execute" can be used to call Embperl from your own modules/scripts (for example from a Apache::Registry or CGI script) or from within another Embperl page to nest multiple Embperl pages (for example to store a common header or footer in a different file).

(See eg/x/Excute.pl for more detailed examples)

When you want to use Embperl::Object call "Embperl::Object::Execute", when you want Embperl::Mail, call "Embperl::Mail::Execute".

There are two forms you can use for calling Execute. A short form which only takes a filename and optional additional parameters or a long form which takes a hash reference as its argument.

  Execute($filename, $p1, $p2, $pn) ;

This will cause Embperl to interpret the file with the name $filename and, if specified, pass any additional parameters in the array @param (just like @_ in a Perl subroutine). The above example could also be written in the long form:

  Execute ({inputfile => $filename,
            param     => [$p1, $p2, $pn]}) ;

The possible items for hash of the long form are are descriped in the configuration section and parameter section.

EXAMPLES for Execute:

 # Get source from /path/to/your.html and
 # write output to /path/to/output'
 Embperl::Execute ({ inputfile  => '/path/to/your.html',
                     outputfile => '/path/to/output'}) ;
 # Get source from scalar and write output to stdout
 # Don't forget to modify mtime if $src changes
 $src = '<html><head><title>Page [+ $no +]</title></head>' ;
 Embperl::Execute ({ inputfile  => 'some name',
                     input      => \$src,
                     mtime      => 1 }) ;
 # Get source from scalar and write output to another scalar
 my $src = '<html><head><title>Page [+ $no +]</title></head>' ;
 my $out ;
 Embperl::Execute ({ inputfile  => 'another name',
                     input      => \$src,
                     mtime      => 1,
                     output     => \$out }) ;
 print $out ;
 # Include a common header in an Embperl page, 
 # which is stored in /path/to/head.html
 
 [- Execute ('/path/to/head.html') -]

Debugging

Starting with 2.0b2 Embperl files can debugged via the interactive debugger. The debugger shows the Embperl page source along with the correct linenumbers. You can do anything you can do inside a normal Perl program via the debugger, e.g. show variables, modify variables, single step, set breakpoints etc.

You can use the Perl interacive command line debugger via

    perl -d embpexec.pl file.epl

or if you prefer a graphical debugger, try ddd (http://www.gnu.org/software/ddd/) it's a great tool, also for debugging any other perl script:

    ddd --debugger 'perl -d embpexec.pl file.epl'

NOTE: embpexec.pl could be found in the Embperl source directory

If you want to debug your pages, while running under mod_perl, Apache::DB is the right thing. Apache::DB is available from CPAN.

Configuration

Configuration can be setup in different ways, depending how you run Embperl. When you run under mod_perl, Embperl add a set of new configuration directives to the Apache configuration, so you can set them in your httpd.conf. When you run Embperl as CGI it takes the configuration from environment variables. For compatibility reason that can also be turned on under mod_perl, by adding "Embperl_UseEnv on" in your httpd.conf. When you call Embperl from another Perl program, by calling the "Execute" function, you can pass your configuration along with other parameters as a hash reference. If you pass "use_env =&lt; 1" als parameter Embperl will also scan the environment for configuration information. Last but not least you can pass configuration information as options when you run Embperl via embpexec.pl from the command line. Some of the configuration options are also setable inside the page via the Empberl objects and you can read the current configuration from these objects.

You can not only pass configuration in different ways, there are also three different contexts: Application, Request and Component. A application describes a set of pages/files that belongs together and form the application. Application level configuration are the same for all files that belongs to an application. These configuration information need to be known before any request processing takes place, so they can't be modified during a request. Every application has it's own name. You can refer the configuration of an application, by simply setting the name of the application to use.

Request level configuration information applies to one request, some of them must be known before the request starts, some of them can still be modified during the request.

Configuration for components can be setup before the request, but can also be passed as argument when you call the component via "Execute".

Embperl_Useenv

EMBPERL_USEENV
$application -> config -> use_env [read only]
off unless running as CGI script
2.0b6

Tells Embperl to scan the enviromemt for configuration settings.

use_redirect_env

$application -> config -> use_redirect_env [read only]
off unless running as CGI script
2.0b6

Tells Embperl to scan the enviromemt for configuration settings which has the prefix "REDIRECT_". This is normally the case when the request is not the main request, but a subrequest.

Embperl_Appname

EMBPERL_APPNAME
$application -> config -> app_name [read only]
2.0b6

Specifies the name for an application. The name is basically used to refer to this application elsewhere in httpd.conf without the need to setup the parameters for the apllication again.

Embperl_App_Handler_Class

EMBPERL_APP_HANDLER_CLASS
$application -> config -> app_handler_class [read only]
2.0b6

Embperl will call the "init" method of the given class at the start of the request, but after all request parameters are setup. This give the class a chance to do any necessary computation and modify the request parameters, before the request is actualy executed. See internationalization for an example.

Embperl_Session_Handler_Class

EMBPERL_SESSION_HANDLER_CLASS
$application -> config -> session_handler_class [read only]
Apache::SessionX
1.3b3
Session Handling

Set the class that performs the Embperl session handling. This gives you the possibility to implement your own session handling.

NOTE: Default until 1.3.3 was "HTML::Embperl::Session", starting with 1.3.4 it is "Apache::SessionX". To get the old session behaviour set it to "HTML::Embperl::Session".

Embperl_Session_Args

EMBPERL_SESSION_ARGS
$application -> config -> session_args [read only]
1.3b3
Session Handling

List of arguments for Apache::Session classes Arguments that contains spaces can be quoted. Example:

  EMBPERL_SESSION_ARGS "DataSource=dbi:mysql:session UserName=www 'Password=secret word'"

Embperl_Session_Classes

EMBPERL_SESSION_CLASSES
$application -> config -> session_classes [read only]
1.3b3
Session Handling

Space separated list of object store and lock manager (and optionally the serialization and id generating class) for Apache::Session (see "Session handling")

Embperl_Session_Config

EMBPERL_SESSION_CONFIG
$application -> config -> session_config [read only]
given when running Makefile.PL of Apache::SessionX
1.3.3
Session Handling

Selects a session configuration from the configurations you have defined when running Apache::SessionX's "Makefile.PL".

NOTE: Use either "EMBPERL_SESSION_CONFIG" or "EMBPERL_SESSION_ARGS" and "EMBPERL_SESSION_CLASSES"

EMBPERL_COOKIE_NAME
$application -> config -> cookie_name [read only]
EMBPERL_UID
1.2b4
Session Handling

Set the name that Embperl uses when it sends the cookie with the session id.

EMBPERL_COOKIE_DOMAIN
$application -> config -> cookie_domain [read only]
none
1.2b4
Session Handling

Set the domain that Embperl uses for the cookie with the session id.

EMBPERL_COOKIE_PATH
$application -> config -> cookie_path [read only]
none
1.2b4
Session Handling

Set the path that Embperl uses for the cookie with the session id.

EMBPERL_COOKIE_EXPIRES
$application -> config -> cookie_expires [read only]
at the end of the session
1.3b5
Session Handling

Set the expiration date that Embperl uses for the cookie with the session id. You can specify the full date or relativ values. The following forms are all valid times:

        +30s                              30 seconds from now
        +10m                              ten minutes from now
        +1h                               one hour from now
        -1d                               yesterday (i.e. "ASAP!")
        now                               immediately
        +3M                               in three months
        +10y                              in ten years time
        Thu, 25-Apr-1999 00:40:33 GMT     at the indicated time & date
EMBPERL_COOKIE_SECURE
$application -> config -> cookie_secure [read only]
at the end of the session
2.0b9
Session Handling

Set the secure flag of cookie that Embperl uses for the session id. If set the cookie will only be transferred over a secured connection.

Embperl_Log

EMBPERL_LOG
$application -> config -> log [read only]
Unix: /tmp/embperl.log Windows: /embperl.log

Gives the location of the log file. This will contain information about what Embperl is doing. The amount of information depends on the debug settings (see "EMBPERL_DEBUG" below). The log output is intended to show what your embedded Perl code is doing and to help debug it.

Embperl_Debug

EMBPERL_DEBUG
$application -> config -> debug

This is a bitmask which specifies what should be written to the log. To specify multiple debugflags, simply add the values together. You can give the value a decimal, octal (prefix 0) or hexadecimal (prefix 0x) value. You can also use the constants defined in Embperl::Constant. The following values are defined:

Show minimum information.
Show memory and scalar value allocation.
Show arguments to and results of evals.
List every request's environment variables.
List posted form data.
Show processing of HTML input tags.
Flush Embperl's output after every write. This should only be set to help debug Embperl crashes, as it drastically slows down Embperl's operation.
Flush Embperl's logfile output after every write. This should only be set to help debug Embperl crashes, as it drastically slows down Embperl's operation.
This feature is not yet implemented in Embperl 2.0!

Inserts a link at the top of each page which can be used to view the log for the current HTML file. See also "EMBPERL_VIRTLOG".

Example:

    EMBPERL_DEBUG 10477
    EMBPERL_VIRTLOG /embperl/log.htm
    <Location /embperl/log.htm>
    SetHandler perl-script
    PerlHandler Embperl
    Options ExecCGI
    </Location>
Shows every time new Perl code is compiled.
Log all HTTP headers which are sent from and to the browser.
Show every variable which is undef'd at the end of the request. For scalar variables, the value before undef'ing is logged.
Enables logging of session transactions.
Show how subroutines are imported in other namespaces.
Logs the process of converting the internal tree strcuture to plain text for output
Logs things related to processing the internal tree data structure of documents
Logs things related to execution of a document
Logs things related to creating the token tables for source parsing
Logs the parseing of the source
Shows how Embperl::Objects searches sourcefiles
Logs cache related things
Gives information about compiling the parsed source to Perl code
Logs things related to XML processing
Logs things related to XSLT processing
Logs things related to checkpoints which are internaly used during execution. This information is only useful if you have a deep knowledge of Embperl internals.

Embperl_Maildebug

EMBPERL_MAILDEBUG
$application -> config -> maildebug
1.2.1

Debug value pass to Net::SMTP.

Embperl_Mailhost

EMBPERL_MAILHOST
$application -> config -> mailhost
localhost

Specifies which host the mail related functions of Embperl uses as SMTP server.

Embperl_Mailhelo

EMBPERL_MAILHELO
$application -> config -> mailhelo
chosen by Net::SMTP
1.3b4

Specifies which host/domain all mailrealted function uses in the HELO/EHLO command. A reasonable default is normally chosen by Net::SMTP, but depending on your installation it may necessary to set it manualy.

Embperl_Mailfrom

EMBPERL_MAILFROM
$application -> config -> mailfrom
www-server@<server_name>
1.2.1

Specifies the email address that is used as sender all mailrelted function.

Embperl_Mail_Errors_To

EMBPERL_MAIL_ERRORS_TO
$application -> config -> mail_errors_to

If set all errors will be send to the email address given.

Embperl_Mail_Errors_Limit

EMBPERL_MAIL_ERRORS_LIMIT
$application -> config -> mail_errors_limit [read only]
2.0b6

Do not mail more then <num> errors. Set to 0 for no limit.

Embperl_Mail_Errors_Reset_Time

EMBPERL_MAIL_ERRORS_RESET_TIME
$application -> config -> mail_errors_reset_time [read only]
2.0b6

Reset error counter if for <sec> seconds no error has occurred.

Embperl_Mail_Errors_Resend_Time

EMBPERL_MAIL_ERRORS_RESEND_TIME
$application -> config -> mail_errors_resend_time [read only]
2.0b6

Mail errors of <sec> seconds regardless of the error counter.

Embperl_Object_Base

EMBPERL_OBJECT_BASE
$application -> config -> object_base [read only]
_base.epl
1.3b1

Name of the base page that Embperl::Objects searches for.

Embperl_Object_App

EMBPERL_OBJECT_APP
$application -> config -> object_app
2.0b6

Filename of the application object that Embperl::Object searches for. The file should contain the Perl code for the application object. There must be no package name given (as the package is set by Embperl::Object) inside the file, but the @ISA should point to Embperl::App. If set this file is searched through the same search path as any content file. After a successful load the init method is called with the Embperl request object as parameter. The init method can change the parameters inside the request object to influence the current request.

Embperl_Object_Addpath

EMBPERL_OBJECT_ADDPATH
$application -> config -> object_addpath
1.3b1

Additional directories where Embperl::Object searches for pages.

This search through the searchpath is always performed if in a call to Execute no path for the file is given.

In httpd.conf or as environment variable directories are separated by ";" (on Unix ":" works also). The parameter for "Execute" and the application object method expects/returns an array reference. This path is always appended to the searchpath.

Embperl_Object_Reqpath

EMBPERL_OBJECT_REQPATH
$application -> config -> object_reqpath
2.0b12

Additional directories where Embperl::Object searches for files for the initial request.

If a file is requested, but cannot be found at the given location, the directories given in the this path are additionally searched for the file. This applies only to the initial filename given to Embperl::Object and not to files called via Execute.

In httpd.conf or as environment variable directories are separated by ";" (on Unix ":" works also). The parameter for "Execute" and the application object method expects/returns an array reference.

Example:

if you say

    Embperl_Object_Reqpath  /a:/b:/c

and you request

    /x/index.epl

it will try

    /x/index.epl
    /a/index.epl
    /b/index.epl
    /c/index.epl

and take the first one that is found.

Embperl_Object_Stopdir

EMBPERL_OBJECT_STOPDIR
$application -> config -> object_stopdir
1.3b1

Directory where Embperl::Object stops searching for the base page.

Embperl_Object_Fallback

EMBPERL_OBJECT_FALLBACK
$application -> config -> object_fallback
1.3b1

If the requested file is not found by Embperl::Object, the file given by "EMBPERL_OBJECT_FALLBACK" is displayed instead. If "EMBPERL_OBJECT_FALLBACK" isn't set a staus 404, NOT_FOUND is returned as usual. If the fileame given in "EMBPERL_OBJECT_FALLBACK" doesn't contain a path, it is searched thru the same directories as "EMBPERL_OBJECT_BASE".

Embperl_Object_Handler_Class

EMBPERL_OBJECT_HANDLER_CLASS
$application -> config -> object_handler_class
1.3b1

If you specify this, the template base and the requested page inherit all methods from this class. This class must contain "Embperl::Req" in his @ISA array.

Embperl_Useenv

EMBPERL_USEENV
$request -> config -> use_env [read only]
off unless running as CGI script
2.0b6

Tells Embperl to scan the enviromemt for configuration settings.

use_redirect_env

$request -> config -> use_redirect_env [read only]
off unless running as CGI script
2.0b6

Tells Embperl to scan the enviromemt for configuration settings which has the prefix "REDIRECT_". This is normally the case when the request is not the main request, but a subrequest.

Embperl_Allow

EMBPERL_ALLOW
$request -> config -> allow [read only]
no restrictions
1.2b10

If specified, only files which match the given perl regular expression will be processed by Embperl. All other files will return FORBIDDEN. This is especially useful in a CGI environment by making the server more secure.

Embperl_Urimatch

EMBPERL_URIMATCH
$request -> config -> urimatch [read only]
process all files
2.0b6

If specified, only files which match the given perl regular expression will be processed by Embperl, all other files will be handled by the standard Apache handler. This can be useful if you have Embperl documents and non Embperl documents (e.g. gifs) residing in the same directory.

 Example: 
 # Only files which end with .htm will processed by Embperl
 EMBPERL_URIMATCH \.htm$

Embperl_Multfieldsep

EMBPERL_MULTFIELDSEP
$request -> config -> mult_field_sep [read only]
\t
2.0b6

Specifies the character that is used to separate multiple form values with the same name.

Embperl_Path

EMBPERL_PATH
$request -> config -> path [read only]
1.3b6

Can contain a semicolon (also colon under Unix) separated file search path. When a file is processed and the filename isn't an absolute path or does not start with ./ (or .\ under windows), Embperl searches all the specified directories for that file.

A special handling is done if the filename starts with any number of "../" i.e. refers to an upper directory. Then Embperl strips the same number of entries at the start of the searchpath as the filename contains "../". "Execute" and the method of the request object expects/returns a array ref.

Embperl_Debug

EMBPERL_DEBUG
$request -> config -> debug

See application configuration for an describtion of possible values

Embperl_Options

EMBPERL_OPTIONS
$request -> config -> options

This bitmask specifies some options for the execution of Embperl. To specify multiple options, simply add the values together.

Disables the automatic cleanup of variables at the end of each request.
Tells Embperl not to send its own errorpage in case of failure, but instead show as much of the page as possible. Errors are only logged to the log file. Without this option, Embperl sends its own error page, showing all the errors which have occurred. If you have dbgLogLink enabled, every error will be a link to the corresponding location in the log file. This option has no effect if optReturnError is set.
With this option set, Embperl sends no output in case of an error. It returns the error back to Apache or the calling program. When running under mod_perl this gives you the chance to use the Apache ErrorDocument directive to show a custom error-document. Inside the ErrorDocument you can retrieve the error messages with 

  $errors = $req_rec -> prev -> pnotes('EMBPERL_ERRORS') ;

where $errors is a array reference. (1.3b5+)

When set every error message not only show the sourcefiles, but all files from which this file was called by Execute.

Embperl_Output_Mode

EMBPERL_OUTPUT_MODE
$request -> config -> output_mode
HTML
2.0b9

Set the desired output format. 0 for HTML and 1 XML. If set to XML all tags that are generated by Embperl will contain a closing slash to conform to XML specs. e.g.

    <input type="text" name="foo" />

NOTE: If you set output_mode to XML you should also change escmode to XML escaping.

Embperl_Output_Esc_Charset

EMBPERL_OUTPUT_ESC_CHARSET
$request -> config -> output_esc_charset [read only]
ocharsetLatin1 = 1
2.0.2

Set the charset which to assume when escaping. This can only be set before the request starts (e.g. httpd.conf or top of the page). Setting it inside the page has undefined results.

UTF-8 or any non known charset. Characters with codes above 128 will not be escaped at all
ISO-8859-1, the default. When a Perl string has it's utf-8 bit set, this mode will behave the same as mode 0, i.e. will not escape anything above 128.
ISO-8859-2. When a Perl string has it's utf-8 bit set, this mode will behave the same as mode 0, i.e. will not escape anything above 128.

Embperl_Session_Mode

EMBPERL_SESSION_MODE
$request -> config -> session_mode [read only]
smodeUDatCookie = 1
2.0b6

Specifies how the id for the session data is passed between requests. Possible values are:

No session id will be passed
The session id for the user session will be passed via cookie
The session id for the user session will append as parameter to any URL and inserted as a hidden field in any form.
The session id for the user session will passed as a part of the URL. NOT YET IMPLEMENTED!!
The session id for the state session will append as parameter to any URL and inserted as a hidden field in any form.

You may add the UDat and SDat values together to get both sorts of sessions, for example the value 0x21 will pass the id for the user session inside a cookie and the id for the state session as parameters.

Embperl_Useenv

EMBPERL_USEENV
$component -> config -> use_env [read only]
off unless running as CGI script
2.0b6

Tells Embperl to scan the enviromemt for configuration settings.

use_redirect_env

$component -> config -> use_redirect_env [read only]
off unless running as CGI script
2.0b6

Tells Embperl to scan the enviromemt for configuration settings which has the prefix "REDIRECT_". This is normally the case when the request is not the main request, but a subrequest.

Embperl_Package

EMBPERL_PACKAGE
$component -> config -> package

The name of the package where your code will be executed. By default, Embperl generates a unique package name for every file. This ensures that variables and functions from one file do not conflict with those of another file. (Any package's variables will still be accessible with explicit package names.)

Embperl_Debug

EMBPERL_DEBUG
$component -> config -> debug

See application configuration for an describtion of possible values

Embperl_Options

EMBPERL_OPTIONS
$component -> config -> options

This bitmask specifies some options for the execution of Embperl. To specify multiple options, simply add the values together.

Disables the automatic cleanup of variables at the end of each request.
Tells Embperl not to send its own errorpage in case of failure, but instead show as much of the page as possible. Errors are only logged to the log file. Without this option, Embperl sends its own error page, showing all the errors which have occurred. If you have dbgLogLink enabled, every error will be a link to the corresponding location in the log file. This option has no effect if optReturnError is set.
With this option set, Embperl sends no output in case of an error. It returns the error back to Apache or the calling program. When running under mod_perl this gives you the chance to use the Apache ErrorDocument directive to show a custom error-document. Inside the ErrorDocument you can retrieve the error messages with 

  $errors = $req_rec -> prev -> pnotes('EMBPERL_ERRORS') ;

where $errors is a array reference. (1.3b5+)

When set every error message not only show the sourcefiles, but all files from which this file was called by Execute.
Tells Embperl to execute the embedded code in a safe namespace so the code cannot access data or code in any other package. (See the chapter about "(Safe-)Namespaces and opcode restrictions" below for more details.)
Tells Embperl to apply an operator mask. This gives you the chance to disallow special (unsafe) opcodes. (See the Chapter about "(Safe-)Namespaces and opcode restrictions" below for more details.)
This option disables the setup of %fdat and @ffld. Embperl will not do anything with the posted form data. Set this when using Execute from your perl script and you have already read the Form Data (via eg. CGI.pm).
By default Embperl checks all formfields in %fdat if they contain valid UTF-8 strings and if yes sets Perl's internals UTF-8 flag.

If this option is set Embperl will never set the UTF-8 on any data in %fdat.

This option will cause Embperl to insert all formfields in %fdat and @ffld, even if they are empty. Empty formfields will be inserted with an empty string. Without this option, empty formfields will be absent from %fdat and @ffld.
Redirects STDOUT to the Embperl output stream before every request and resets it afterwards. If set, you can use a normal Perl print inside any Perl block to output data. Without this option you can only use output data by using the [+ ... +] block, or printing to the filehandle OUT.
Normally, if there is a value defined in %fdat for a specific input field, Embperl will output a hidden input element for it when you use hidden. When this option is set, Embperl will not output a hidden input element for this field when the value is a blank string.
Disable the removal of spaces and empty lines from the output. This is useful for sources other than HTML.
Change current working directory to the directory of the sourcefile, before executing the source.

Embperl_Escmode

EMBPERL_ESCMODE
$component -> config -> escmode
7

Turn HTML and URL escaping on and off.

NOTE: If you want to output binary data, you must set the escmode to zero.

For convenience you can change the escmode inside a page by setting the variable $escmode.

The result of a Perl expression is always XML-escaped (e.g., `>' becomes `&gt;' and ' become &apos;).
The result of a Perl expression is HTML-escaped (e.g., `>' becomes `&gt;') in normal text and URL-escaped (e.g., `&' becomes `%26') within of "A", "EMBED", "IMG", "IFRAME", "FRAME" and "LAYER" tags.
The result of a Perl expression is always URL-escaped (e.g., `&' becomes `%26').
The result of a Perl expression is always HTML-escaped (e.g., `>' becomes `&gt;').
No escaping takes place.
If you add this value to the above Embperl will always perform the escaping. Without it is possible to disable escaping by preceding the item that normally is escaped with a backslash. While this is a handy thing, it could be very dangerous in situations, where content that is inserted by some user is redisplayed, because they can enter arbitrary HTML and precede them with a backslash to avoid correct escaping when their input is redisplayed again.

NOTE: You can localize $escmode inside a [+ +] block, e.g. to turn escaping temporary off and output $data write

    [+ do { local $escmode = 0 ; $data } +]

Embperl_Input_Escmode

EMBPERL_INPUT_ESCMODE
$component -> config -> input_escmode [read only]
0
2.0b6

Tells Embperl how to handle escape sequences that are found in the source.

0
don't interpret input (default)
1
unescape html escapes to their characters (i.e. &lt; becomes < ) inside of Perl code
2
unescape url escapes to their characters (i.e. %26; becomes & ) inside of Perl code
3
unescape html and url escapes, depending on the context

Add 4 to remove html tags inside of Perl code. This is helpful when an html editor insert html tags like <br> inside your Perl code.

Set EMBPERL_INPUT_ESCMODE to 7 to get the old default of Embperl < 2.0b6

Set EMBPERL_INPUT_ESCMODE to 0 to get the old behaviour when optRawInput was set.

Embperl_Input_Charset

EMBPERL_INPUT_CHARSET
$component -> config -> input_charset

If set to the value "utf8" the source is interpreted as utf8 encoded so you can use utf8 literals. It has the same effect as adding "use utf8" to a normal Perl script.

Embperl_Top_Include

EMBPERL_TOP_INCLUDE
$component -> config -> top_include
2.0b10

Give a pieces of code that is include at the very top of every file.

Example:

    Embperl_Top_Include "use MY::Module;"

This will cause MY::Module to be used in every page. Note that Embperl_Top_Include must contain valid Perl code and must be ended with a semicolon.

NOTE: If you pass top_include as parameter to Execute it is only used in case the code is compiled (or recompiled) and not cached.

Embperl_Cache_Key

EMBPERL_CACHE_KEY
$component -> config -> cache_key [read only]
2.0b1

literal string that is appended to the cache key

Embperl_Cache_Key_Options

EMBPERL_CACHE_KEY_OPTIONS
$component -> config -> cache_key_options [read only]
all options set
2.0b1

Tells Embperl how to create a key for caching of the output

include the PathInfo into CacheKey
include the QueryInfo into CacheKey
don't cache POST requests (not yet implemented)

Embperl_Expires_Func

EMBPERL_EXPIRES_FUNC
$component -> config -> expires_func [read only]
2.0b1

Function that is called every time before data is taken from the cache. If this function returns true, the data from the cache isn't used anymore, but rebuilt.

Function could be either a coderef (when passed to Execute), a name of a subroutine or a string starting with "sub " in which case it is compiled as anonymous subroutine.

NOTE: If &EXPIRES is defined inside the page, it get evaluated before the excecution of the page

Embperl_Cache_Key_Func

EMBPERL_CACHE_KEY_FUNC
$component -> config -> cache_key_func
2.0b1

function that should be called when build a cache key. The result is appended to the cache key.

Embperl_Expires_In

EMBPERL_EXPIRES_IN
$component -> config -> expires_in [read only]
2.0b1

Time in seconds that the output should be cached. (0 = never, -1 = forever)

NOTE: If $EXPIRES is set inside the page, it get evaluated before the excecution of the page

Embperl_Expires_Filename

EMBPERL_EXPIRES_FILENAME
$component -> config -> expires_filename [read only]
2.0b8

Cache should be expired when the given file is modified.

Embperl_Syntax

EMBPERL_SYNTAX
$component -> config -> syntax
Embperl
2.0b1

Used to tell Embperl which syntax to use inside a page. Embperl comes with the following syntaxes:

all the HTML tags that Embperl recognizes by default
all the [ ] blocks that Embperl supports
(default; contains EmbperlHtml and EmbperlBlocks)
<% %> and <%= %>, see perldoc Embperl::Syntax::ASP
Server Side Includes, see perldoc Embperl::Syntax::SSI
File contains pure Perl (similar to Apache::Registry), but can be used inside EmbperlObject
File contains only Text, no actions are taken on the Text
Defines the <mail:send> tag, for sending mail. This is an example for a taglib, which could be a base for writing your own taglib to extent the number of available tags
translates pod files to XML, which can be converted to the desired output format by an XSLT transformation
Can be used to process word processing documents in RTF format

You can get a description for each syntax if you type

    perldoc Embperl::Syntax::xxx

where 'xxx' is the name of the syntax.

You can also specify multiple syntaxes e.g.

    EMBPERL_SYNTAX "Embperl SSI"
    Execute ({inputfile => '*', syntax => 'Embperl ASP'}) ;

The 'syntax' metacommand allows you to switch the syntax or to add or subtract syntaxes e.g.

    [$ syntax + Mail $]

will add the Mail taglib so the <mail:send> tag is available after this line.

    [$ syntax - Mail $]

now the <mail:send> tag is unknown again

    [$ syntax SSI $]

now you can only use SSI commands inside your page.

Embperl_Recipe

EMBPERL_RECIPE
$component -> config -> recipe [read only]
2.0b4

Tells Embperl which recipe to use to process this component

Embperl_Xsltstylesheet

EMBPERL_XSLTSTYLESHEET
$component -> config -> xsltstylesheet [read only]
2.0b5

Tell the xslt processor which stylsheet to use.

Embperl_Xsltproc

EMBPERL_XSLTPROC
$component -> config -> xsltproc [read only]
depends on compiltime options
2.0b5

Tells Embperl which xslt processor to use. Current "libxslt" and "xalan" are supported by Embperl, but they must be compiled in to be available.

Parameters

Parameters gives addtionaly information about the current request or the execution of the current component. So we have two sorts of parameters Request and Component parameters. Request parameters are automatically setup by Embperl with information Embperl takes from the current running environment. When Embperl is invoked via the "Execute" function, you can pass any of the parameters to Execute. Component parameters mainly reflect the parameters given to "Execute".

filename

$request -> param -> filename
2.0b6

Gives the filename of the file that was actualy requested. Inside of the applications "init" function it can be changed to force Embperl to serve a different file.

unparsed_uri

$request -> param -> unparsed_uri
2.0b6

The full unparsed_uri, includeing the query_string and the path_info.

uri

$request -> param -> uri
2.0b6

The decoded path of the unparsed_uri.

server_addr

$request -> param -> server_addr
2.0b9

URL of the server of the current request in the form schema://addr:port/ e.g. http://perl.apache.org/ (port is omitted if it is an default port)

path_info

$request -> param -> path_info
2.0b6

The path_info, that is anything in the path after the file the is currently served.

query_info

$request -> param -> query_info
2.0b6

Any parameters passed in a GET request after the question mark. The hash %fdat will contain these values in a already decoded and easy to use way. So it's normly more convenient to use %fdat instead.

language

$request -> param -> language
2.0b6

The primary langange found in the browser "Accept-Language" HTTP header. This value is used for all language-dependent functions inside Embperl. You can set it change the selection of message returned by "$request -&gt; gettext" and "[= =]".

cookies

$request -> param -> cookies
2.0b6

A hashref that contains all cookies send by the browser to the server.

cgi

$request -> param -> cgi [read only]
2.0b12

Holds the CGI.pm object, which is used for file upload. If no file uploaded data is send to the request, this member is undefined.

inputfile

$component -> param -> inputfile [read only]
1.0.0

Give the name of the file that should be processed, e.g.

    Execute({inputfile => 'mysource.epl'}) ;

There is a shortcut when you only need to give the input file and no other parameters. The above is will do the same as:

    Execute('mysource.epl') ;

outputfile

$component -> param -> outputfile [read only]
STDOUT
1.0.0

Specify a file to which the output should be written. Example:

    Execute({inputfile  => 'mysource.epl',
             outputfile => 'myoutput.htm'}) ;

input

$component -> param -> input [read only]
1.0.0

This parameter is used, when you have the source already in memory. You should pass a reference to a scalar that contains the source. Addtionaly you should give the inputfile parameter, to allow Embperl caching to keep track of different in memory sources. The mtime parameter is used to tell Embperl's cache if the source has change since the last call or not. If "mtime" if "undef" or of a different value as it was during the last call, the source is considered to be changed and everything is recompiled. Example:

    # Get source from scalar
    # Don't forget to modify mtime if $src changes
    $src = '<html><head><title>Page [+ $no +]</title></head>' ;
    Embperl::Execute ({ inputfile  => 'some name',
                     input      => \$src,
                     mtime      => 1 }) ;

output

$component -> param -> output [read only]
1.0.0

Gives the possibility to write the output into a scalar instead of sending it to stdout or a file. You should give a reference to a scalar. Example:

    Execute({inputfile  => 'mysource.epl',
             output     => \$out}) ;

sub

$component -> param -> sub [read only]
1.2.0

Call the given Embperl subroutine defined with "[$sub$]" inside the page. A shortcut for this is to append the name of the subroutine after the filename with a hash sign, so the following calls are doing the same thing:

    Execute('mysource.epl#mysub') ;
    Execute({inputfile  => 'mysource.epl',
             sub        => 'mysub'}) ;

If you leave out the filename, the sub is called in the current file, so this can only be used inside a file that is already processed by Embperl.

subreq

$component -> param -> subreq
2.0b8, Apache 2.x

This utilizies Apache 2.0 filters to retrieve the output of a sub-request and uses it as input for the current component. For example if you have a CGI-Script and you need to post process it via Embperl or simply want to include it's output in another Embperl/Embperl::Object document you can write:

    [- Execute ({subreq => '/cgi-bin/script.cgi'}) -]

NOTE: You have to specify a URI and not a filename!

import

$component -> param -> import [read only]
1.3.0

A value of one tells Embperl to define the subrountines inside the file (if not already done) and to import them as perl subroutines into the current namespace.

See [$ sub $] metacommand and section about subroutines for more info.

A value of zero tells Embperl to simply precompile all code found in the page. (With 2.0 it is not necessary anymore to do it before using the "sub" parameter on a different file).

firstline

$component -> param -> firstline [read only]
1
1.2.0

Specifies the first linenumber of the sourcefile.

mtime

$component -> param -> mtime [read only]
undef
1.0.0

Last modification time of parameter input. If undef the code passed by input is always recompiled, else the code is only recompiled if mtime changes.

param

$component -> param -> param [read only]
1.0.0

Can be used to pass parameters to the Embperl document and back. Must contain a reference to an array. Example:

    Execute({inputfile  => 'mysource.epl',
             param      => [1, 2, 3]}) ;
    Execute({inputfile  => 'mysource.epl',
             param      => \@parameters}) ;

There is a shortcut, so the following code the aquivalent (NOTE: Don't use a array ref here):

    Execute('mysource.epl', 1, 2, 3) ;
    Execute('mysource.epl', @parameters) ;

The array @param in the Embperl document is setup as an alias to the array. See eg/x/Excute.pl for a more detailed example.

fdat

$component -> param -> fdat [read only]
1.0.0

Pass a hash reference to customly set %fdat. If "ffld" is not given, "ffld" will be set to "keys %fdat".

ffld

$component -> param -> ffld [read only]
1.0.0

Pass a array reference to customly set @fdat. Does not affect %fdat.

object

$component -> param -> object [read only]
1.3.2

Takes a filename and returns an hashref that is blessed into the package of the given file. That's useful, if you want to call the subs inside the given file, as methods. By using the "isa" parameter (see below) you are able to provide an inherence tree. Additionally you can use the returned hashref to store data for that object. Example:

  [# the file eposubs.htm defines two subs: txt1 and txt2 #]
  [# first we create a new object #]
  [- $subs = Execute ({'object' => 'eposubs.htm'}) -]
  [# then we call methods inside the object #]
  txt1: [+ $subs -> txt1 +] <br>
  txt2: [+ $subs -> txt2 +] <br>

isa

$component -> param -> isa [read only]
1.3.2

Takes a name of a file and pushes the package of that file into the @ISA array of the current file. By using this you can setup an inherence tree between Embperl documents. Is is also useful within Embperl::Object. Example:

    [! Execute ({'isa' => '../eposubs.htm'}) !]

errors

$component -> param -> errors [read only]
1.3.0

Takes a reference to an array. Upon return, the array will contain a copy of all errormessages, if any.

xsltparam

$component -> param -> xsltparam
%fdat
2.0b6

Takes a reference to hash which contains key/value pair that are accessible inside the stylesheet via <xsl:param>.

Embperl's Objects

There are three major objects in Embperl: application, request and component. Each of these objects can be used to get information about the processing and control the execution. Each of these objects has a config sub-object, which makes the configuration accessible and, where possible, changeable at runtime. The "config" method of these three objects returns a reference to the configuration object. The methods of these configurations objects are described in the section Configuration. The request and the component object have addtionaly a parameter sub-object, which holds parameters passed to the current request/component. The "param" method of these two objects returns the parameter sub-object. The methods of these parameter objects can be found in the section Parameters. Addtionaly each of the three major objects has a set of own methods, which are described here.

thread

$application -> thread [read only]
2.0b6

Returns a reference to a object which hold per threads information. There is only one such object per thread.

curr_req

$application -> curr_req [read only]
2.0b6

Returns a reference to the current request object i.e. the object of the request currently running.

config

$application -> config [read only]
2.0b6

Returns a reference to the configuration object of the application. See section Configuration.

user_session

$application -> user_session [read only]
2.0b6

Returns a reference to the user session object.

state_session

$application -> state_session [read only]
2.0b6

Returns a reference to the state session object.

app_session

$application -> app_session [read only]
2.0b6

Returns a reference to the application session object.

udat

$application -> udat [read only]
2.0b6

Returns a reference to a hash which contains the data of the user session. This has can be used to access and modify user session data. It's the same as accessing the global %udat.

sdat

$application -> sdat [read only]
2.0b6

Returns a reference to a hash which contains the data of the state session. This has can be used to access and modify state session data. It's the same as accessing the global %sdat.

mdat

$application -> mdat [read only]
2.0b6

Returns a reference to a hash which contains the data of the application session. This has can be used to access and modify application session data. It's the same as accessing the global %mdat.

errors_count

$application -> errors_count
2.0b6

Contains the number of errors since last time send per mail. See also mail_errors_to.

errors_last_time

$application -> errors_last_time
2.0b6

Time when the last error has occurred. See also mail_errors_to.

errors_last_send_time

$application -> errors_last_send_time
2.0b6

Time when the last mail with error messages was sent. See also mail_errors_to.

apache_req

$request -> apache_req [read only]
2.0b6

Returns a reference to mod_perls Apache request object. In mod_perl 1 this is of type "Apache::" in mod_perl 2 it's a "Apache2::RequestRec".

config

$request -> config [read only]
2.0b6

Returns a reference to the configuration object of the request. See section Configuration.

param

$request -> param [read only]
2.0b6

Returns a reference to the parameter object of the request. See section Parameters.

component

$request -> component [read only]
2.0b6

Returns a reference to the object of component currently running. See component methods below.

app

$request -> app [read only]
2.0b6

Returns a reference to the object of application to which the current request belongs. See application methods above.

thread

$request -> thread [read only]
2.0b6

Returns a reference to a object which hold per threads information. There is only one such object per thread.

request_count

$request -> request_count [read only]
2.0b6

Returns the number of request handled so far by this child process.

request_time

$request -> request_time [read only]
2.0b6

Start time of the current request.

session_mgnt

$request -> session_mgnt [read only]
2.0b6

Set to true if session management is available.

session_id

$request -> session_id [read only]
2.0b6

Combined id of current user and state session.

session_state_id

$request -> session_state_id [read only]
2.0b6

Id of the current state session as received by the browser, this means this method returns "undef" for a new session.

session_user_id

$request -> session_user_id [read only]
2.0b6

Id of the current user session as received by the browser, this means this method returns "undef" for a new session.

$request -> cookie_expires
2.1.1

Can be used to retrieve the actual expiration date that Embperl uses for the cookie with the session id.

had_exit

$request -> had_exit [read only]
2.0b6

True if exit was called in one of the components processed so far.

log_file_start_pos

$request -> log_file_start_pos [read only]
2.0b6

File possition of the log file at the time when the request has started.

error

$request -> error
2.0b6

True if there were any error during the request.

errors

$request -> errors
2.0b6

Reference to an array which holds all error messages occurred so far.

errdat1

$request -> errdat1
2.0b6

Additional information passed to the error handler when an error is reported.

errdat2

$request -> errdat2
2.0b6

Additional information passed to the error handler when an error is reported.

lastwarn

$request -> lastwarn
2.0b6

Last warning message.

errobj

$request -> errobj
2.0rc3

The object passed to the last die, if any. This is useful when you pass an object to die inside an Execute. After the Execute you can check $epreq -> errobj, to get the object. The object is also push to the array passed to the errors parameter of Execute.

cleanup_vars

$request -> cleanup_vars
2.0b6

Reference to an array which is filled with references to variables that should be cleaned up after the request. You can add your own variables that needs cleanup here, but you should never remove any variables from this array.

cleanup_packages

$request -> cleanup_packages
2.0b6

Reference to a hash which contains all packages that must be cleaned up after the request.

initial_cwd

$request -> initial_cwd [read only]
2.0b6

Working directory when the request started.

messages

$request -> messages
2.0b6

Reference to an array of hashs of messages. This is used by Embperl to translate message into different languages. When a "[= =]" block is processed or $request -> gettext is called, Embperl searches this array. It starts from the first element in the array (each element in the array must be a hashref) and tries to lookup the text for the given symbol in hash. When it fails it goes to the next array element. This way you can setup multiple translation tables that are search for the symbol. Example:

    %messages =
        (
        'de' =>
            {
            'addsel1' => 'Klicken Sie auf die Kategorie zu der Sie etwas hinzufügen möchten:',
            'addsel2' => 'oder fügen Sie eine neue Kategorie hinzu. Bitte geben Sie die Beschreibung in so vielen Sprachen wie Ihnen möglich ein.',
            'addsel3' => 'Falls Sie die Übersetzung nicht wissen, lassen Sie das entsprechende Eingabefeld leer.',
            'addsel4' => 'Kategorie hinzufügen',
            },
         'en' =>
            {
            'addsel1' => 'Click on the category for which you want to add a new item:',
            'addsel2' => 'or add new category. Please enter the description in as much languages as possible.',
            'addsel3' => 'If you don\'t know the translation leave the corresponding input field empty.',
            'addsel4' => 'Add category',
            }
        ) ;
    $lang = $request -> param -> language ;
    push @{$request -> messages}, $messages{$lang} ;
    push @{$request -> default_messages}, $messages{'en'} if ($lang ne 'en') ;

"$request -" param -> language> retrieves the language as given by the browser language-accept header (or set before in your program). Then it pushes the german or english messages hash onto the message array. Addtionaly it pushes the english messages on the default_messages array. Messages will be taken from this array if nothing can be found in the messages array.

default_messages

$request -> default_messages
2.0b6

Reference to an array with default messages. Messages will be taken from this array if nothing can be found in the messages array.

config

$component -> config [read only]
2.0b6

Returns an reference to the configuration object of the component.

param

$component -> param [read only]
2.0b6

Returns an reference to the parameter object of the component.

req_running

$component -> req_running [read only]
2.0b6

True if Embperl is inside of the execution of the request.

sub_req

$component -> sub_req [read only]
2.0b6

True is this is not the outermost Embperl component, i.e. this component is called from within another component.

inside_sub

$component -> inside_sub [read only]
2.0b6

True is we are inside a Embperl subroutine ([$ sub $] ... [$ endsub $])

had_exit

$component -> had_exit [read only]
2.0b6

True if the exit was called during the excution of the component.

path_ndx

$component -> path_ndx [read only]
2.0b6

Tells Embperl how much parts of the path should be ignored when searching through the path.

cwd

$component -> cwd [read only]
2.0b6

Directory of the source file of the component.

sourcefile

$component -> sourcefile [read only]
2.0b6

Source file of the component.

syntax

$component -> syntax
2.0b6

Syntax of the component

prev

$component -> prev [read only]
2.0b6

Previous component, e.g. the component which called this component.

import_stash

$component -> import_stash [read only]
2.0b6

While importing a component this is set to the stash to which symbols are imported. "undef" during normal execution.

exports

$component -> exports
2.0b6

Symbols that should be exported by this component.

curr_package

$component -> curr_package [read only]
2.0b6

Name of the package the component is executed in.

code

$component -> code
2.0b6

Only valid during compile phase. Can used to retrieve and modify the code Embperl is generating. See Embperl::Syntax for more details and Embperl::Syntax::RTF for an example.

2023-01-22 perl v5.36.0