Table of Contents

Driven User Guide

version 1.2-eap-11

Using Annotations with Cascading Applications

Annotations display metadata about flow and step nodes on the application details and slice performance views of Driven. Click on a node in the directed acyclic graph (DAG) to view annotations about the operation, such as processing details for a tap, filter, or function of a flow.

Annotation_function

Figure 1: Sample annotation displaying the Function type within the wc flow

The types of metadata that are exposed in annotations are selected as part of Cascading application development.

Note
Use Cascading 2.6 to assign annotations to Cascading functions and taps. Also, refer to the Cascading 2.6 core API reference for details about the cascading.management.annotation package.

Driven renders all the application metadata associated with the annotations. However, for privacy and compliance reasons, you may want to restrict access to information about a certain Property to a subset of Driven users. Access control becomes an important feature if you want to restrict visibility of some metadata attributes to comply with privacy or governance guidelines in a shared, multitenant cluster.

In the following code example, the visibility rule is applied for users based on their identity in Driven. In the following example, the visibility rule is set to PUBLIC:

@Property(name = "scrubTextConvert", visibility = Visibility.PUBLIC)
@PropertyDescription("_my_property_description_")
...
@Property(name = "scrubText", visibility = Visibility.PUBLIC)
@PropertyDescription("_my_property_description_")
...

Driven maps the visibility levels listed in the table below to the state of the user session.

Table 1. Visibility Levels
Property (user session) Public Access (Anonymous) Protected Access (Login) Private Access (Team)

PUBLIC

X

X

X

PROTECTED

X

X

PRIVATE

X

This mapping can be configured in the driven.properties file in order to effect your governance guidelines. The example below illustrates a typical use of the visibility levels.

The default visibility mapping effectively means the properties control viewing of information in the following manner:
PUBLIC

Allow metadata attributes to be observed anonymously, by default.

PROTECTED

Allow metadata attributes to be viewed by users who log in to Driven.

PRIVATE

Allow metadata attributes to be viewed by members of a Driven team. This level is also used when access is restricted by role, such as Driven admin or team leader.

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