Transforms

Transforms

Transforms modify taxonomy values when generating event keys.

They are defined in opentp.yaml as named pipelines of steps and referenced in spec.events.key.pattern using {field | transformName}.

Defining Transforms

opentp.yaml

spec:
  transforms:
    slug:
      - lower
      - trim
      - replace:
          from: " "
          to: "_"
      - truncate: 160

Each step is either:

• a string step name (e.g. lower)
• a single-key object with parameters (e.g. replace: { from: " ", to: "_" })

Using Transforms

opentp.yaml

spec:
  events:
    key:
      pattern: "{area | slug}::{event | slug}"

Built-in Steps

• lower, upper, trim
• replace, truncate
• collapse, keep
• to-snake-case, to-kebab, to-camel-case, to-underscore
• transliterate

Custom Steps

Load additional transform steps from a directory:

opentp validate --external-transforms ./my-transforms

Example step module:

my-transforms/reverse/index.js

module.exports = {
  name: "reverse",
  factory: () => (value) => value.split("").reverse().join(""),
};