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Policy Template Language Functions

Functions make it possible to compute values dynamically, for example by concatenating multiple values together or extracting sub-text from an API response. The syntax for calling a function is:

<function>(<term>, <term>, …)

For example:

size($volumes)

Functions can accept a number of basic types as parameters. These basic types strongly parallel what you might find in JSON or JavaScript:

  • Number—a number can be an integer or floating point value.
  • String—a string value, denoted with "".
  • Boolean—true or false.
  • Regexp—a regular expression value. Always denoted in the language with // brackets. For example, the function which accepts a Regexp might be called like contains("hello world", /hello/)
  • Array—an array of any of the other values.
  • Object—an object is a hash or map of values. See the policy template language Syntax for details.
  • Datasource, Resource—Datasources and resources are treated as an array of objects if used as a parameter to a function

Click the appropriate link below to learn more about a specific function: