Op templates are data blueprints that represent a particular kind of operation. They are templates because they are used to create possibly many operations to be executed. For example, you may have only one op template that you use to drive a billion operations to a system under test, or you may have a myriad of different access patterns. In either case, all the operations that you want to execute must be defined in template form beforehand.

As templates, you indicate where the variable parts are filled in when needed. How this is done will be explained in the bindings section.

Simple statements

In essence, the config format is all about configuring operations. Every other element in the config format is in some way modifying or otherwise helping create operations to be used in an activity.

Op templates are the single most important part of a YAML config.

# a single operation
ops:
  - a single statement body

This is a valid activity YAML file in and of itself. It has a single op template.

It is up to the individual activity types like cql, or stdout to interpret the op template in some way. The example above is valid as an operation in the stdout activity, but it does not produce a valid CQL statement when used with the CQL activity type. The contents of the op can be provided as free-form text. If the op template is valid CQL, then the CQL activity type can use it without throwing an error. Each activity type determines what a statement means, and how it will be used.

Multiple Op Templates

You can specify multiple op templates:

ops:
  - This is a statement, and the file format doesn't know how statements will be used!
  - submit job {alpha} on queue {beta} with options {gamma};

YAML formatting prefixes

You can use the YAML pipe to put them on multiple lines, indented a little further in:

ops:
  - |
    This is a statement, and the file format doesn't
    know how statements will be used!
  - |
    submit job {alpha} on queue {beta} with options {gamma};

There are a few other useful YAML line prefixes which behave slightly differently.

Op Naming

Op templates can be named:

ops:
  - s1: |
  This is a statement, and the file format doesn't
  know how statements will be used!
  - s2: |
  submit job {alpha} on queue {beta} with options {gamma};

Actually, every op template in a YAML file has a name. If you don't provide one, then a name is auto-generated for the op template based on its position in the YAML file.

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