List Filter

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Description

The List Filter processor filters events based on the presence of a specific value in a list field. It:

• Checks if a value exists in a list
• Filters events based on list membership
• Preserves original event data
• Works with any list field type
• Supports exact value matching

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Required Input

The processor requires an input event stream with at least one list field to filter on.

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Configuration

List Field

Select the list field to check for the required value. The field must be a list type.

Required Value

Specify the value to look for in the list. The processor will only output events where this value is present in the selected list field.

Output

The processor outputs only those events where the specified value is found in the selected list field.

Example

Input Event

{
  "sensor_id": "sensor1",
  "measurements": [22.1, 23.4, 24.2, 25.0, 25.5]
}

Configuration

• List Field: measurements
• Required Value: 25.0

Output Event

The processor will output the event because 25.0 is present in the measurements list.

Use Cases

1. Data Filtering

   • Filter events by list membership
   • Select specific value occurrences
   • Filter based on value presence
   • Create value-based subsets

2. Event Selection

   • Select events with specific values
   • Filter based on value existence
   • Create value-based event streams
   • Implement value-based routing

3. Quality Control

   • Filter valid measurements
   • Select events with expected values
   • Filter based on value criteria
   • Implement value-based validation

Notes

• The processor performs exact value matching
• Original event data is preserved
• The processor works with any list field type
• Events are only output if the value is found
• List order does not affect filtering