Metadata variables

Introduction

Payload metadata variables (known as meta variables) can be added by custom scripts and also by the set variables shape.

There may be times when you need to define variables or parameters for a process flow step using values from the incoming payload metadata. This can be achieved using a specific payload syntax in the process flow connection shape.

Need to know

Payload metadata cannot exceed 10240 bytes. Exceeding this limit will cause the process flow to fail on the associated step.

Referencing meta variables

Payload metadata can be accessed via a variable or parameter field using the syntax below:

[[meta.unique_key]]

For example:

[[meta.id]]

When defining variables you can 'mix and match' payload, metadata and flow variables. For example:

When a payload is passed to a 'child' process flow via the run process flow shape, meta variables are included.

Related information

• Payload variables

• Flow variables

• Generating dynamic cache keys with variables