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Types and Data Structures

Overview​

This document outlines some of the common types and data structures defined by OpenFeature and referenced elsewhere in this specification.

Boolean​

A logical true or false, as represented idiomatically in the implementation languages.

String​

A UTF-8 encoded string.

Number​

A numeric value of unspecified type or size. Implementation languages may further differentiate between integers, floating point numbers, and other specific numeric types and provide functionality as idioms dictate.

Structure​

Structured data, presented however is idiomatic in the implementation language, such as JSON or YAML.

Datetime​

A language primitive for representing a date and time, including timezone information.

Evaluation Details​

A structure representing the result of the flag evaluation process, and made available in the detailed flag resolution functions, containing the following fields:

  • flag key (string, required)
  • value (boolean | string | number | structure, required)
  • error code (string, optional)
  • reason (string, optional)
  • variant (string, optional)

Resolution Details​

A structure which contains a subset of the fields defined in the evaluation details, representing the result of the provider's flag resolution process, including:

  • value (boolean | string | number | structure, required)
  • error code (string, optional)
  • reason (string, optional)
  • variant (string, optional)

NOTE: The resolution details structure is not exposed to the Application Author. It defines the data which Provider Authors must return when resolving the value of flags.

Evaluation Options​

A structure containing the following fields:

  • hooks (one or more hooks, optional)