bp deprecations

keystoneclient needs a consistent way to notify applications that deprecated behavior is being used.

Problem Description

keystoneclient doesn’t advertise deprecations consistently. All these techniques are used:

  • A comment in the code.

  • The Docstring mentions it.

  • Python’s warnings module is used.

  • A FIXME comment that says to deprecate it

When things aren’t deprecated properly they’re not really deprecated. A comment in the code isn’t going to be visible to developers. Developers can’t be expected to read the code to figure out what’s deprecated.

Proposed Change

keystoneclient will use a consistent way to advertise deprecations. The proposed way is to use oslo’s debtcollector. For example, when a deprecated function is going to be removed, use debtcollector.removals.remove.


The existing deprecations, comment deprecations, etc., will be changed to use debtcollector.


Use python’s regular warnings module. debtcollector provides more consistent messaging.

Security Impact

By deprecating things properly we’ll be able to remove the code and have less code to maintain with potential security problems.

Notifications Impact


Other End User Impact

Depending on how the application has configured debtcollector already, they may see the application fail, print errors, etc.

Performance Impact


Other Deployer Impact


Developer Impact

Developers will use debtcollector for deprecations rather than warnings, logs, etc.



Primary assignee:

<blk-u> Brant Knudson

Work Items

  • Change existing uses of DeprecationWarning to use debtcollector.

  • Find places where comments or deprecations used to indicate deprecation and use debtcollector instead.

  • Find places where FIXME was used to indicate to deprecate something and use debtcollector.



Documentation Impact

The keystoneclient documentation will be changed to say that the library uses debtcollector for deprecations.