Storing plugin metadata in transformations and jobs

Owned by Former user (Deleted)
Last updated: Jul 31, 2013Version comment
2 min read

Attributes Interface

Sometimes a plugin needs to add metadata to a transformation or a step, a job or a job entry.  To make this easy we made TransMeta, StepMeta, JobMeta and JobEntryCopy implement the org.pentaho.di.core.AttributesInterface:

 public interface AttributesInterface {
  
  /**
   * Pass a map of group attributes
   * @param attributesMap The map of group attributes
   */
  public void setAttributesMap(Map<String, Map<String, String>> attributesMap);
  
  /**
   * @return All attributes for all attribute groups in one single map.
   */
  public Map<String, Map<String, String>> getAttributesMap();  
  
  /**
   * Add a map of attributes to an attribute group.
   * @param groupName The group to add the attributes to 
   * @param attributes the attributes to add
   */
  public void setAttributes(String groupName, Map<String, String> attributes);
  
  /**
   * Add an attribute to an attribute group
   * @param groupName The group to add the attribute to
   * @param key The key of the attribute
   * @param value the value of the attribute
   */
  public void setAttribute(String groupName, String key, String value);
    
  /**
   * Get an attributes map for a group
   * @param groupName The name of the attributes group to retrieve
   * @return The map representing the attributes group
   */
  public Map<String, String> getAttributes(String groupName);
  
  /**
   * Get a value for an attribute in an attribute group
   * @param groupName The group to get the attribute from
   * @param key The attribute key
   * @return The attribute value of null if the group of key doesn't exist
   */
  public String getAttribute(String groupName, String key);
  
}

This interface allows you to store key/value pairs.  The metadata is automatically stored and retrieved together with the transformation or job in question, either through XML or through your repository of choice.

Annotations

You can use this interface to add information which is all by itself meaningless for the core logic of Kettle but very useful to an installed plugin.  The plugin can then act upon this information.  As such, it's very much like an annotation.