Adding and Removing Proxies

Introduction

The proxies name and label have a major role in ParaView : they are used to create graphical and python interface. This has a big impact on how the users will discover features but it is also important at deprecation time.

Naming

When adding a new proxy to ParaView you should give it a name (and label). You should try to find a good name at first to make it discoverable and also because it is not so easy to change it afterward (see below).

So here are some guidelines:

1. make it concise: easier to read and remember
2. make it meaningful: describe what it does (that other filters do not)
3. avoid generic words: they can apply to too many things

For instance: AppendLocationAttributes was renamed to Coordinates and GenerateProcessIds simply to ProcessIds.

XML attributes

The <Proxy> and the <Property> tags (and derivative, such as SourceProxy etc) have two important attributes, name and label.

The name is used as an internal reference. It is the key for pvsm, the xml based statefile.

The label is used for user interfaces. This includes obviously the Graphical Interface, through menus, but also the python wrapping. In the python case, a sanitized version of the label is used, to be a valid function name.

If label is not defined, name is used instead.

The label is also translatable for the Graphical Interface (not for python).

Deprecation

When a proxy is intended for deprecation (for a future removal for instance), different things should be done, specially to ensure backward compatibility.

When a proxy is deprecated, the following files should probably be updated:

• *.xml: the servermanager file declaring the proxy. Add a <Deprecated> tag with explanation.
• ParaViewFilters.xml: to expose new proxy in ParaView.
• vtkSMStateVersionController.cxx for pvsm backward compatibility. It uses proxy name.
• _backwardscompatibilityhelper.py for python backward compatibility. It uses proxy label.
• Documentation/release/dev/<my-change>.md to document the change in release note
• Testing/XML/*.xml: the XML test(s) using this proxy
• Testing/Python/*.py: python tests using this proxy

Python

To enable backwards compatibility in a python script, use the following lines at the top of the script:

import paraview
paraview.compatibility.major = 5
paraview.comptatbility.minor = 6