ETL Pentaho Code Learning Notes

1, by setting the KETTLE_HOME environment variable can let. Kettle do not need under User.home

2, the default kettle_home is User.home, if you want to customize the environment variables need to set Kettle_home

3. In the. Kettle directory, you can place the following files or directories:

Filename	Description
kettle.proper ties
. languagechoice	set the language of the operation to facilitate the interface language translation -- content :localedefault=en_us Localefailover=en_u
Other	You can also place the plugins directory and add your own extensions

4, the type of plug-in:

Directory load XML configuration file name under Type plugin

Step steps kettle-steps.xml

Partitioner steps ...

Jobentry jobentries ...

Repository repositories ...

Database databases ...

Lifecycle repositories ...

Rules rules ...

5, plug-in loading

A. Scan directory: <kettle_home>/plugins, < Run directory >/plugins, <kettle_home>/plugins/< 4th type to corresponding directory >,, < Run Directory >/plugins/< 4th type to corresponding directory >

Description: The first two scan declarations, the latter two are scan XML definition files.

You can set all the defined classpath to be used for debugging in a comma-delimited kettle_plugin_classes variable.

B. First approach: defining a common XML format structure

(1) Steps/step (see Kettle-steps.xml)

Subordinate sex or element: ID, description, iconfile, tooltip, category (compatible with i18n), classname, ErrorHelpFile

Example:

<step id= "Injector" >

<description>i18n:org.pentaho.di.trans.step:BaseStep.TypeLongDesc.Injector</description> <!--

: The name of the plugin is displayed

with i18n: Start by: Delimited, the first part is the PA where the message resides The Ckage path, and the second part is its message key.

-

<classname>org.pentaho.di.trans.steps.injector.InjectorMeta</classname> <!--

: Class for Plug-ins

-

<category>i18n:org.pentaho.di.trans.step:BaseStep.Category.Inline</category> <!--

: Name Display of plugin category

with i18n: Start by: Delimited, the first part is the PA where the message resides The Ckage path, and the second part is its message key.

-

<tooltip>i18n:org.pentaho.di.trans.step:BaseStep.TypeTooltipDesc.Injector</tooltip>

<iconfile>ui/images/INJ.png</iconfile>

</step>

(2) libraries/library (plugin reference jar, can be multiple)

under Properties: Name (relative to a path to the current plug-in directory)

(3) localized_category/category (plug-in category display text, can be multiple)

under Properties: Locale (Specify the country language code, such as: EN_US,ZH_CN

Value: the corresponding text

(4) Localized_description/description (plugin description text, can be multiple)

under Properties: Locale (Specify the country language code, such as: EN_US,ZH_CN

Value: the corresponding text

(5) Localized_tooltip/tooltip (plugin hint text, can be multiple)

under Properties: Locale (Specify the country language code, such as: EN_US,ZH_CN

Value: the corresponding text

C. Second way: Scan

<kettle_home>/plugins, < Run directory >/plugins, <kettle_home>/plugins/< 4th type to corresponding directory > All of the jar packages in these three directories have type-corresponding declared classes (this method needs to be done through the definition file)

type of interface corresponding to the Declaration class

Step Org.pentaho.di.trans.step.StepMetaInterface Org.pentaho.di.core.annotations.Step

Partitioner Org.pentaho.di.core.annotations.PartitionerPlugin

Jobentry Org.pentaho.di.job.entry.JobEntryInterface Org.pentaho.di.core.annotations.JobEntry

Repository Org.pentaho.di.core.annotations.RepositoryPlugin

Database Org.pentaho.di.core.plugins.DatabaseMetaPlugin

Lifecycle Org.pentaho.di.core.annotations.LifecyclePlugin

Importrule Org.pentaho.di.core.annotations.ImportRulePlugin

C. Third, load the built-in. xml file, such as: Kettle-engine.jar inner root directory. xml file.

such as: Kettle-variables.xml,kettle-steps.xml,kettle-job-entries.xml

can also be influenced by environment variables: Steps (kettle_core_steps_file), Jobentry (Kettle_core_jobentries_file)

6, performance Optimization tip: You can properly remove some unnecessary plug-ins, which will speed up the Spoon development tool startup speed.

such as: Agilebi, ETC.,

ETL Pentaho Code Learning Notes