Stacking¶

TL;DR — Combines multiple data sources by taking a configured number of items from each source in turn.

When to use¶

Combines multiple attached data sources by taking a configured number of items from each source in sequence and repeating that pattern until the sources are exhausted or a count limit is reached.

It is useful when you need a predictable mix of payload families rather than consuming one data source completely before moving to the next. It can also keep looping over finished generators when you want a longer mixed stream.

YAML configuration¶

Use the hook name in the matching runtime section, then place hook-specific fields under the configuration object shown in the examples below.

Minimal example¶

DataSources:
  - Name: PriorityPayloads
    Generator: FromFileSystem
    GeneratorConfiguration:
      DataArrangeOrder: AsciiAsc
      FileSystem:
        Path: sample-data/priority
        SearchPattern: '*.json'
      StorageMetaData: ItemName

  - Name: StandardPayloads
    Generator: FromFileSystem
    GeneratorConfiguration:
      DataArrangeOrder: AsciiAsc
      FileSystem:
        Path: sample-data/standard
        SearchPattern: '*.json'
      StorageMetaData: ItemName

  - Name: MixedPayloads
    Generator: Stacking
    DataSourceNames:
      - PriorityPayloads
      - StandardPayloads
    GeneratorConfiguration:
      Count: 5
      LoopFinishedGenerators: true
      ItemsPerGenerator:
        - 2
        - 1

Realistic example¶

MixedPayloads takes two items from PriorityPayloads, then one item from StandardPayloads, and repeats that pattern until it has produced five generated items.

Because LoopFinishedGenerators is enabled, the stacking process can continue even if one source runs out earlier than the other.

Edge cases¶

• Missing required configuration keys fail schema validation before the hook runs.
• Keep hook names and referenced session or data-source names aligned with the surrounding YAML.

See also¶

• Configuration table
• YAML scaffold
• Generators