Light development in Magnolia

Light development is a modern front-end development approach that simplifies and speeds up development in Magnolia. A key feature is that configuration of common definitions, like dialogs and templates, moves out of JCR and onto the file system as YAML text files. As a developer you have all your code and configuration in the same place in files. This makes templates easier to understand, share, merge and manage in source control. Template scripts and configuration now live side-by-side in the same place.

Thanks to the resource loading mechanism, Magnolia picks up any changes to the files right away without a restart, whether they reside on the Java classpath or file system. These simplifications accelerate project development in both Java Maven modules and the light modules.

An additional benefit of the file system approach is that project teams or third party developers can easily create tools to generate Magnolia configuration.

Light modules

Magnolia introduced light modules as part of the light development approach.

The Magnolia CLI speeds up creating and developing light modules. The tool includes commands to install and start Magnolia, and to create modules, pages and components.

Develop Magnolia projects without Java skills

Now front-end developers can create Magnolia projects with light modules without the need for Java development skills, or even an SDK or Java IDE.

A light module is simply a directory on the file system that contains YAML definition files, FreeMarker template scripts, and other resource files of any type. The file system approach is more familiar to most front-end developers, and this allows them to get up to speed fast in Magnolia. They can use all of their familiar tools, text editors, IDEs and build processes.

While light modules open Magnolia to front-end developers, Java is still the key to the deep integration and customization capabilities of Magnolia.

Light modules and Maven modules

The light module approach aligns with traditional Java development: A project can be built with both Maven and light modules. Additionally, because the structure of light modules dovetails perfectly with Maven modules, a light module can easily be transformed into a Maven module by copying its contents into the Maven module. As a project architect, now you have the flexibility to build your project with the technologies that make the most sense for your project and team.

Light development capabilities

What can you do with light development now?

All of the following light development features are available in both Maven modules and light modules.

The following tasks are currently possible in light development:

What is next for light development?

We are working on expanding light development functionality.

See light development items on the Magnolia Roadmap.

What is not supported in light modules?

Resource storage and loading in light development

Resources include:

Magnolia’s resource loading cascade includes hot-reload from the file system. See Light modules and Resources for more.

The following example works equally well as a light module, or in the src/main/resources directory of a Maven module.

β”œβ”€β”€ apps
β”œβ”€β”€ dialogs
β”‚ └── myDialog.yaml
β”œβ”€β”€ webresources
└── templates
    β”œβ”€β”€ components
    └── pages
        └── my-template
            β”œβ”€β”€ myTemplate.yaml
            └── myTemplate.ftl

Definitions in light development

Definitions in light development are coded via text files in YAML format. You can configure templates, dialogs, apps, and themes in YAML.

Example: Simple page template definition.

renderType: freemarker
templateScript: /my-module/templates/pages/home.ftl
dialog: my-module:pages/homePageProperties

Configuration of system parameters for light development

You can set the following properties in your file when developing light modules.

What is magnolia.develop

magnolia.develop is a configuration property that can be set to true in the file for development purposes, specifically to:

  • Enable info.magnolia.classpathwatch.ClasspathScanner, when developing via IDE and changing/deploying edited classpath-based resources.

  • Disable the cache for resources.

What is magnolia.resources.dir?

magnolia.resources.dir is a property defining the directory from which resources are loaded in a Magnolia instance. This directory is used for file-based resources such as light modules and for overriding classpath resources. The property is configured in WEB-INF/config/default/ and its default value is $magnolia.home/modules. To see the current value of the property, go to the Config Info tab in the About Magnolia app.

You can use symbolic links (symlinks or soft links) in the resources directory to include light modules located elsewhere on your system.

Set the magnolia.resources.filesystem.observation.excludedDirectories property to exclude directories from being observed for changes. (See the table in the Configuration management: Defining properties section.)

What is magnolia.content.bootstrap.dir

magnolia.content.bootstrap.dir is a property defining the directory from which bootstrap XML files are loaded in a Magnolia instance. This directory is only used for file-based bootstrap. The directory can reside anywhere on the file system. The property is configured in WEB-INF/config/default/ see the current value of the property, see the list of properties in the About Magnolia app Config Info tab.

What is magnolia.resources.watcher.sensitivity

magnolia.resources.watcher.sensitivity is a property that defines the sensitivity (speed) with which the changes of the resources in magnolia.resources.dir are observed by info.magnolia.dirwatch.DirectoryWatcherService. The property can be set in the configuration file to one of the following values: low, medium, high. If not set explicitly in the configuration file, the DirectoryWatcherService works by default under the high value. This is ideal for development purposes on OSX. It is recommended that you leave the property set to high.

What is magnolia.yaml.maxAliasesForCollections

Since version 1.26 of the SnakeYAML processor for JVM, there is a maximum of 50 aliases for getMaxAliasesForCollections to prevent a Billion Laughs Attack.

The magnolia.yaml.maxAliasesForCollections property, introduced with Magnolia 6.2.17, allows you to adjust the limit if the default value is too low and breaks parsing of aliases in YAML files.

The property is configured in WEB-INF/config/default/ To see the current value of the property, see the list of properties in the About Magnolia app Config Info tab.

Check out our partner’s Magnolia YAML assistant IntelliJ plugin to increase your efficiency in Magnolia light development.

The plugin significantly reduces the effort of light development in YAML with Magnolia CMS. Created for developers by developers, it automates the most time-consuming activities during light development [like]:

  • jumping into components, templates, dialogs by reference

  • autocompleting the schema for Magnolia light modules definitions

  • changing file references during rename & move

— Ray Sono AG
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