Js Chilkat2 Perl Reference Documentation

Chilkat2::Js

Current Version: 11.7.0

Markdown version of this page for AI tools (v 11.7.0) · all AI docs

Chilkat.Js

Execute sandboxed JavaScript inside an application with controlled access to Chilkat features.

Use Chilkat.Js when an application needs to execute JavaScript internally while retaining control over what the script is allowed to access. By default, scripts run in a closed sandbox with the JavaScript language and standard library available, but without filesystem, network, or Chilkat class access unless the host application explicitly enables those capabilities.

Embedded JavaScript engine

Run JavaScript code from inside the host application without launching an external scripting process.

Sandboxed by default

Start from a restricted execution environment and selectively expose only the capabilities the script should use.

Enable Chilkat classes

Allow scripts to use selected Chilkat classes when the host application wants JavaScript to perform controlled Chilkat operations.

Filesystem restrictions

Optionally restrict filesystem access so scripts can read or write only within approved locations.

Script input and output

Execute JavaScript, pass data through the host-controlled environment, and retrieve results or diagnostics from the script run.

Controlled automation

Use JavaScript as an embedded extension language for application-defined workflows while keeping host resources protected.

Common pattern: Create a Js object, load or provide the JavaScript code, enable only the Chilkat classes and filesystem locations the script is permitted to use, run the script, and inspect the result or diagnostic output. Use Chilkat.Js when the application needs scriptability with a security boundary controlled by the host.
Third-Party Notice This software includes portions of the QuickJS JavaScript engine. Copyright © 2017–2024 Fabrice Bellard. Licensed under the MIT License. The Chilkat Js engine was originally derived from QuickJS, but has been extensively modified.

Object Creation

use Chilkat2;

my $js = Chilkat2::Js->new;
# or set properties (and RaiseError) at creation:
# my $js = Chilkat2::Js->new(VerboseLogging => 1, RaiseError => 1);
my $js = Chilkat2::Js->new(Property => $value, ...);

Creates the object. The optional pairs set writable properties (and RaiseError) in order, as if set one by one; an unknown or read-only name croaks. use Chilkat2; loads every class; the Chilkat2/Js.pm file holds only this class's documentation (perldoc Chilkat2::Js).

Perl frees the object when its last reference goes (undef $js, or the variable going out of scope); there is nothing to close. Objects returned by methods are independent and freed the same way. The class may be subclassed (use parent -norequire, 'Chilkat2::Js';): an object is a blessed hash reference whose hash is free for the subclass's own fields.

my $boolVal = $js->RaiseError;
$js->RaiseError($boolVal);

When false (the default), a method that fails returns false (or undef), and the reason is in LastErrorText. When true, it dies with a Chilkat2::Error instead, as DBI does with its RaiseError. Objects returned by a method inherit the value of the object that returned them.

Errors

A Chilkat2::Error stringifies to the failed call's full LastErrorText, and has the methods text, class ('Chilkat2::Js'), method (the method name) and object. Methods that look something up and find nothing return undef without dying (each such method says so), methods that answer a question (HasMember, IsUnlocked, ...) return a plain boolean, and property reads and writes never fail for Chilkat reasons.

Misuse always croaks, with your file and line, whatever RaiseError is: a wrong number of arguments, a reference or undef where a string or number is expected, an object of the wrong class, an out-of-range integer, a string containing a NUL character, a wide character in a byte string, or a write to a read-only property.

Strings are Perl character strings in both directions (length, regexes and :encoding layers see characters); binary data (BinData) is a byte string. Unlocking: call Chilkat2::Global->new->UnlockBundle('...') once at startup.

Properties

DebugLogFilePath
# $strVal is a string
my $strVal = $js->DebugLogFilePath;
$js->DebugLogFilePath($strVal);

If set to a file path, this property logs the LastErrorText of each Chilkat method or property call to the specified file. This logging helps identify the context and history of Chilkat calls leading up to any crash or hang, aiding in debugging.

Enabling the VerboseLogging property provides more detailed information. This property is mainly used for debugging rare instances where a Chilkat method call causes a hang or crash, which should generally not happen.

Possible causes of hangs include:

  • A timeout property set to 0, indicating an infinite timeout.
  • A hang occurring within an event callback in the application code.
  • An internal bug in the Chilkat code causing the hang.

More Information and Examples
top
LastErrorHtml
# $strVal is a string (read-only)
my $strVal = $js->LastErrorHtml;

Provides HTML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

top
LastErrorText
# $strVal is a string (read-only)
my $strVal = $js->LastErrorText;

Provides plain text information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

top
LastErrorXml
# $strVal is a string (read-only)
my $strVal = $js->LastErrorXml;

Provides XML-formatted information about the last called method or property. If a method call fails or behaves unexpectedly, check this property for details. Note that information is available regardless of the method call's success.

top
LastMethodSuccess
# $boolVal is a boolean
my $boolVal = $js->LastMethodSuccess;
$js->LastMethodSuccess($boolVal);

Indicates the success or failure of the most recent method call: 1 means success, 0 means failure. This property remains unchanged by property setters or getters. This method is present to address challenges in checking for null or Nothing returns in certain programming languages. Note: This property does not apply to methods that return integer values or to boolean-returning methods where the boolean does not indicate success or failure.

top
TimeoutSeconds
# $intVal is an integer
my $intVal = $js->TimeoutSeconds;
$js->TimeoutSeconds($intVal);
Introduced in version 11.4.0

Specify a timeout in seconds to prevent JavaScript from running indefinitely, such as in an infinite loop. By default, the value is 0, meaning no timeout is set and infinite loops will continue forever.

More Information and Examples
top
VerboseLogging
# $boolVal is a boolean
my $boolVal = $js->VerboseLogging;
$js->VerboseLogging($boolVal);

If set to 1, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is 0. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

top
Version
# $strVal is a string (read-only)
my $strVal = $js->Version;

Version of the component/library, such as "10.1.0"

More Information and Examples
top

Methods

CallFunction
# $funcJson is a Chilkat2::JsonObject
# $resultJson is a Chilkat2::JsonObject
# $success is true or false
my $success = $js->CallFunction($funcJson, $resultJson);
Introduced in version 11.4.0

Calls a JavaScript function. The function name and arguments are passed in $funcJson. The result is returned in $resultJson.

Returns true on success, false on failure; LastErrorText says why. With RaiseError on, a failure dies with a Chilkat2::Error instead (it stringifies to the LastErrorText); the object remains usable either way.

top
ConsoleOutputSb
# $sb is a Chilkat2::StringBuilder
$js->ConsoleOutputSb($sb);
Introduced in version 11.4.0

Returns the console output in $sb from the last call to Eval .

Returns the object, so calls can be chained.

More Information and Examples
top
Eval
# $jscript is a Chilkat2::StringBuilder
# $resultJson is a Chilkat2::JsonObject
# $success is true or false
my $success = $js->Eval($jscript, $resultJson);
Introduced in version 11.4.0

Run $jscript as a script. Return output and errors in $resultJson.

Returns true on success, false on failure; LastErrorText says why. With RaiseError on, a failure dies with a Chilkat2::Error instead (it stringifies to the LastErrorText); the object remains usable either way.

top
SetCkPermission
# $chilkatClassName is a string
# $permission is a string
# $success is true or false
my $success = $js->SetCkPermission($chilkatClassName, $permission);
Introduced in version 11.4.0

Sets sandbox related permissions for Chilkat objects. The $chilkatClassName is the name of the Chilkat class (case-insensitive), such as Http, Rest, "MailMan", "Ftp2", "Ssh", etc. The $chilkatClassName can also be set to "all" to apply the permission to all Chilkat classes.

Possible values for $permission are:

  • disable - Your JavaScript code is not allowed to create an instance of the Chilkat class. A JavaScript exception is thrown when trying to create a Chilkat object of a class that is disabled.
  • sandbox - Objects for the Chilkat class can be instantiated in JavaScript, but they have no read or write access to the local filesystem.
  • readOnly - Objects for the Chilkat class can be instantiated in JavaScript and have read-only access to the local filesystem.
  • writeOnly - Objects for the Chilkat class can be instantiated in JavaScript and have write-only access to the local filesystem.
  • readWrite - Objects for the Chilkat class can be instantiated in JavaScript and have read/write access to the local filesystem.

By default, all Chilkat classes are disabled. Your application must enable "all" or specific Chilkat classes before calling Eval or CallFunction .

Returns true on success, false on failure; LastErrorText says why. With RaiseError on, a failure dies with a Chilkat2::Error instead (it stringifies to the LastErrorText); the object remains usable either way.

More Information and Examples
top