Property files are used for configuration during the startup sequence before the repository is available. These properties configure the instance for a particular use (such as a development or production environment) and set various system directories. Once the startup sequence is completed and the repository is available, the majority of configuration is done in the
config workspace in the repository.
Properties are not stored in a single property file but come from multiple sources. These sources are processed or parsed in the order shown in this table:
|Source||Location||Path / Comment|
|2.||Module properties||module descriptor|
|3.||Global file properties||web application|
|4.||Default file properties||web application|
|5.||Web application file properties||web application|
|6.||Server file properties||web application|
|7.||Web application at server file properties||web application|
|8.||System properties||JVM (-Dx=y)||Existing properties will be overriden by available System properties|
Sources processed earlier may be overridden by sources processed later. The processing order and distribution of properties into several sources allows for flexible customization. The following are key properties set in the default
Multiple configurations on a single Web application archive
Default properties are common regardless of the server name or webapp name. Webapp specific properties are installed only if the webapp name matches. Correspondingly, server specific properties are only installed if the server name matches. For example, Magnolia ships with two webapps by default:
It is possible to set a different persistence manager per environment. For example, on the development instance you could use the default embedded Derby database, whilst on production you could use a production-scale persistent storage such as a MySQL database.
See WAR file with multiple configurations for more on this topic.
The MySQL InnoDB storage engine is supported by Magnolia, the MyISAM engine is not. InnoDB is the default engine in MySQL 5.5 and later.
The structure and the order of source execution allows you to provide sophisticated configurations and flexible customization. The default Magnolia configuration (delivered in the web application bundle) provides an example of how the mechanism works:
Magnolia provides a single web application which configures itself depending on the servlet context it is installed in. If your environment has multiple staging systems with differing configuration needs, you can apply different configurations by adding a server name to each of the listed paths.
For complex environments, the order of loading files can be defined in
WEB-INF/web.xml as a
Properties can be accessed through the static methods of the Magnolia'
info.magnolia.cms.core.SystemProperty class. The following table lists the properties:
Location of a log4j config file. Can be a .properties or .xml file. The value can be:
Directory containing XML files for initialization of a blank Magnolia instance. If no content is found in any of the repositories, they are initialized by importing the XML files found in this folder. If you don't want to let Magnolia initialize repositories automatically then remove this parameter.
Directory used for cached pages.
Password for repository connection.
User ID for repository connection.
History directory used for activation.
Repository configuration, points to an XML file.
requiredif you have any clustered workspaces in your project
Identifies the instance as a cluster master node. During installation and update Magnolia bootstraps content only into master nodes. This ensures that other (replica) nodes installed later don't override already bootstrapped content.
Example: Public instance A is defined as a cluster master node. The instance starts and creates a clustered
Temporary directory for uploaded files.
Location of private and public keys used for activation .
Set an instance as author (
Some modules contain optional sample content. They will check this property to decide if they should install the content.
default is none
List of component class names to be excluded from component instantiation. Separate class names with white space (space, tab) or commas.
Enables support for JSR 250 annotations. Magnolia uses the
Directory where logs are written.
Migration module 1.2.2+ Turns off migration report generation to speed up the migration process. Set to
Repository home directory.
Jackrabbit configuration, points to an XML file.
Jackrabbit configuration file for a clustered repository.
Always define the
Set to true if bootstrapping and update should be performed automatically after installation. This simply means the system won't wait for the user to start the update manually.
Activate UTF-8 support for pages.
default is set in set in Jackrabbit configuration file
The ID of the JCR cluster instance.
When setting the value in magnolia.properties, it overrides the value set in the Jackrabbit configuration file; this allows using a single configuration file for all the cluster instances.
In addition to these examples you can define arbitrary properties (
magnolia.home is one example).
Properties can be used to prefixother path-like properties. For example, in
magnolia.cache.startdir is set by substituting the root directory with property
magnolia.app.rootdir. See WAR file with multiple configurations on how to use properties to target a deployment environment.
You can extend a configuration by defining an
extends property and setting its value to the source configuration you want it to inherit. The target configuration inherits everything from the source and adds its own exceptions. This can save time and effort as you only need to define exceptions explicitly. The mechanism is only available in the
config repository. In the example below, the
demo-project site definition extends the
default site definition.
The definition inherits all configuration from the
default configuration and adds its own domains, internationalization and URI-to-repository mappings. The
extends property can point to the source configuration with an absolute or relative path.
Extending is additive by default, which means that configuration specified at the extending level is added to the inherited configuration. Setting the
extends property to
override changes this behavior. An override allows the extending node to completely remove the inherited content and replace it with its own content entries. In the example below, the
demo-project site definition supports two locales,
en (English) and
de (German), whereas site
demo-project-fr is targeted to French speakers only.
The French site extends
demo-project. It inherits all configuration except the locales. An override under the locales node removes
de. Only the French locale
fr defined at this level is applied. This means that authors can enter only French content on the French site.
Observation is a feature of the Java Content Repository that enables applications to register interest in events that describe changes to a workspace. The applications can then monitor and respond to those events. The observation mechanism dispatches events when a persistent change is made to the workspace. Magnolia uses observation heavily. For instance, observation is used to reload module configurations and to reload all objects provided by the FactoryUtil. To use observation you must at least specify the workspace, the path to the node which should be observed, and an event listener. The event listener's
onEvent() method is called whenever there are changes in the observed node. Magnolia provides a helper class
to assist you in using observation for your project. For more information please refer to the Javadoc.
Most configuration is stored in the config workspace. To transfer the repository stored configuration into a Java object, a mechanism called Node2Bean is used. Node2Bean populates a Java Bean from the content of a repository node including sub nodes. Note that configuration details are not restricted to the config node. The following table shows where the Node2Bean mechanism is currently used.
|Where it is used||What is configured|
|Basic server configuration: instance type (author, public), default base URL and default extension|
|Mapping virtual URIs to pages.|
|Messages for localized labels and descriptions in the UI.|
|Commands and command catalogs.|
|Builds a component configured in the repository.|
|Guice Provider that creates an object by reading it from the repository.|
|RendererProvider that instantiates a renderer from a configuration node.|
|TemplateDefinitionProvider that instantiates a template from a configuration node.|
For developers, module configuration (
ModuleManagerlmpl) using the module class is the most important current usage of Content2Bean.
Node2Bean in module instances
Module configuration data is transferred into a Bean from
/modules/<module name>/config. The Bean class to build is defined in the module descriptor XML file.
Components. If a path in the config workspace is given rather than a concrete class name, then Node2Bean is used to build the component instance.
Additional items such as components, templates and virtual URI mappings are configured at module level.
Node2Bean analyses the bean's "setter" and "adder" methods using introspection and uses them if a suitable configuration value is available. With "adder" methods (using the singular form of the node names) you can populate collections and maps. With this mechanism, Node2Bean can support all possible data types:
- Simple data types like String, int, long, float, double, boolean (to specify "true" you can use "true", TRUE", or "1") with the suitable "setter" method
- Other data types matching the "setter" method's signature
- Collections with String values or other data types by specifying a class property
- Maps with keys and values as Strings or other data types by specifying a class property
All sub elements are also built using Node2Bean.
The class used to instantiate an object through the Node2Bean mechanism is determined through reflection or by explicitly referencing a class in the class node data. By referencing a specific class you can override Magnolia default configuration and implement your own caching behavior, security mechanism and so on.
config: Entry point of the transformation. In the module descriptor
SampleConfigclass is used. Set
sub: Subbean. The class is determined using reflection if it is not explicitly defined.
items: Collection. The corresponding
addmethod is used to determine the class and populate the collection if existing.
item2: Special item with its own class and additional properties.
parameters: Collection of key-value pairs.
Simple data types
Values with simple data types must be defined as properties. Each property name must match its respective setter method.
To configure a collection you have to create a sub node and a suitable "setter" method:
- All properties of the collection node will create simple String entries in the collection. The properties' names are not used by Node2Bean, only the values.
- All sub nodes of the collection node will be treated as objects of the type specified in the
classproperty in the sub node. If no class attribute is specified, a Map will be created instead. The sub nodes' names are not used by Node2Bean.
- All sub nodes of the collection node will be treated as maps unless they have a ".". The properties' names and the sub nodes' names are not used by Node2Bean.
The rules to populate a map are the same as with collections, except that the properties' names and the sub nodes' names are used as key values.
Example: cache configuration
The configuration creates an object of type CacheConfiguration This class needs public suitable setter or adder methods.
Note that all necessary setters are available. For the
executors node there are setter and adder methods. As the adder is more specific the
setExecutors method will not be used.
This is what happens with
Since there is a class property defined, let's look at the Default class that Node2Bean uses to create the new object.
Now let's have a look at the addExecutor
(String name, CachePolicyExecutor executor) method in CacheConfiguration and the configuration:
As this method has two arguments, the node name
bypass is passed as the first argument and a
Bypass object as the second argument. Because
CachePolicyExecutor is an interface, the implementing class is specified.
Voters are used in Magnolia whenever configuration values are not assigned at startup but instead depend on rules. For example the cache module has to determine if a requested resource may be cached or not. The rules to determine values should be configurable. The rules are user-defined using voters which evaluate established criteria by determining true or false of each rule. Voters are currently used for:
- Filter configuration: uses voters to determine whether a filter should be executed or bypassed.
- Cache configuration: uses voters to determine whether a file should be cached or not.
The basic concept of voters uses Voter classes which calculate an
int vote value, where positive (1, 2, 3, ...) results are treated as "yes" or "true" and (0, -1, -2, ...) results are treated as "no" or "false". If you have a set of voters, then the result of a voting is the largest absolute result. If there are two voters with the same absolute result, then the one with the higher positive value will be taken.
|Vote results||VoterSet result|
|-3, 0, 2||-3|
|-3, 0, 3||3|
|-3, 0, 4||4|
For most of the "real world" voters only boolean results make sense. These boolean voters return "1" for a "true" and "0" for a "false" result.
|none||Yes||Checks if the current user is authenticated.|
For further information, please see the voters package summary.