/* This file is part of the KTextTemplate library SPDX-FileCopyrightText: 2009, 2010 Stephen Kelly SPDX-License-Identifier: LGPL-2.1-or-later */ #ifndef KTEXTTEMPLATE_ENGINE_H #define KTEXTTEMPLATE_ENGINE_H #include "template.h" #include "templateloader.h" namespace KTextTemplate { class TagLibraryInterface; class EnginePrivate; /// @headerfile engine.h /** @brief **%KTextTemplate::Engine** is the main entry point for creating %KTextTemplate Templates. The **%KTextTemplate::Engine** is responsible for configuring and creating Template objects. In typical use, one or more AbstractTemplateLoader objects will be added to the Engine to load template objects, and plugin directories will be set to enable finding template tags and filters. @code auto engine = new Engine(); auto loader = QSharedPointer::create(); loader->setTemplateDirs( {"/usr/share/myapp/templates"} ); engine->addTemplateLoader( loader ); engine->addPluginPath( "/usr/lib/myapp" ); auto template1 = engine->newTemplate( "Template content", "template name" ); auto template2 = engine->loadByName( "templatefile.html" ); @endcode Once it is configured, the **%Engine** can be used to create new templates by name by loading the templates with the @ref loadByName method, or by defining the content in the @ref newTemplate method. By default the builtin tags and filters distributed with %KTextTemplate are available in all templates without using the @gr_tag{load} tag in the template. These pre-loaded libraries may be configured if appropriate to the application. For example, an application which defines its own tags and filters may want them to be always available, or it may be desirable to restrict the features available to template authors by removing built in libraries. Different **%Engine** objects can be used to create templates with differing configurations. @section smart_trim Insignificant whitespace The output of rendering a template depends on the content of the template. In some cases when generating content in which whitespace is significant, this can have undesired effects. For example, given a template to generate C++ code like: @verbatim class MyClass { {# This loop creates the #} {# methods in the class #} {% for method in methods %} {% if method.hasDox %} {{ method.dox }} {% endif %} {{ method.signature }} {% endfor %} }; @endverbatim The output would have a lot of whitespace which is not necessarily wanted. @code class MyClass { void foo() const; }; @endcode It is possible to strip insignificant whitespace by enabling the smartTrim feature with @ref setSmartTrimEnabled. When enabled the output will not contain a newline for any line in the template which has only one token of template syntax, such as a comment, tag or variable. @code class MyClass { void foo() const; }; @endcode @author Stephen Kelly */ class KTEXTTEMPLATE_EXPORT Engine : public QObject { Q_OBJECT public: /** Constructor */ Engine(QObject *parent = {}); /** Destructor. */ ~Engine() override; /** Returns the TemplateLoaders currently configured on the **%Engine**. */ QList> templateLoaders(); /** Adds @p loader to the TemplateLoaders currently configured on the **%Engine**. */ void addTemplateLoader(QSharedPointer loader); /** Sets the plugin dirs currently configured on the **%Engine** to @p dirs. @warning This overwrites the default paths. You normally want @ref addPluginPath. @see @ref finding_plugins */ void setPluginPaths(const QStringList &dirs); /** Prepend @p dir to the list of plugin dirs. */ void addPluginPath(const QString &dir); /** Removes all instances of @p dir from the list of plugin dirs. */ void removePluginPath(const QString &dir); /** Returns the currently configured plugin dirs */ QStringList pluginPaths() const; /** Returns a URI for a media item with the name @p name. Typically this will be used for images. For example the media URI for the image "header_logo.png" may be "/home/user/common/header_logo.png" or "/home/user/some_theme/header_logo.png" depending on the @ref templateLoaders configured. This method will not usually be called by application code. To load media in a template, use the @gr_tag{media_finder} template tag. */ std::pair mediaUri(const QString &fileName) const; /** Load the Template identified by @p name. The Templates and plugins loaded will be determined by the **%Engine** configuration. */ Template loadByName(const QString &name) const; /** Create a new Template with the content @p content identified by @p name. The secondary Templates and plugins loaded will be determined by the **%Engine** configuration. */ Template newTemplate(const QString &content, const QString &name) const; /** Returns the libraries available by default to new Templates. */ QStringList defaultLibraries() const; /** Adds the library named @p libName to the libraries available by default to new Templates. */ void addDefaultLibrary(const QString &libName); /** Removes the library named @p libName from the libraries available by default to new Templates. */ void removeDefaultLibrary(const QString &libName); /** Returns whether the smart trim feature is enabled for newly loaded templates. @see smart_trim This is false by default. */ bool smartTrimEnabled() const; /** Sets whether the smart trim feature is enabled for newly loaded templates. @see smart_trim */ void setSmartTrimEnabled(bool enabled); #ifndef K_DOXYGEN /** @internal Loads and returns the libraries specified in defaultLibraries or @p state. */ void loadDefaultLibraries(); /** @internal Loads and returns the library specified by @p name in the current **%Engine** configuration or @p state. Templates wishing to load a library should use the @gr_tag{load} tag. */ TagLibraryInterface *loadLibrary(const QString &name); #endif private: Q_DECLARE_PRIVATE(Engine) EnginePrivate *const d_ptr; }; } #endif