Concepts

yams has a number of proprietary concepts which help to model data and simulations. Understanding these concepts is not required to use the tooling, but can help make sense of the documentation and errors associated with the tool.

Sources

Getting data into yams revolves around the concept of a Source, which contains definitions for principals, resources, policies, accounts, etc. Sources are read periodically by the yams server to keep data fresh.

Entities

An Entity is a loose term to describe a thing associated with simulation. Included in the definition of Entities are:

• Principals
• Groups
• Resources
• Policies
• Tags
• Accounts
• Org Nodes

Universe

A Universe is a container which holds all known Entities. The most commonly used Universe would be the one representing baseline reality as defined by a set of Sources, however full or partial alternative Universes can be constructed as desired.

Overlay

An Overlay or Overlay Universe is similarly a container of Entities, but has the purpose of redefining or overriding Entity definitions defined in a base Universe. Priority is always given to the Overlay when resolving configurations.