Edge Delta Add Field Processor

The Edge Delta Add Field Processor inserts a field with a static value into telemetry data, using conditions and the OTTL set function.

5 minute read

Overview

This processor is used to add a field with a static value to all data items. It provides flexibility for updating or assigning values within the telemetry data structure and is most effective when used in conjunction with a condition.

Configuration

You specify a name for the processor as well as the field and static value to add. You can add more than one field and you can make the addition conditional.

The user interface builds the OTTL statements for you. This processor uses the set OTTL function to transform the data item:

- name: Multiprocessor
  type: sequence
  processors:
  - type: ottl_transform
    metadata: '{"id":"aNrtlRIR18GyaifGvX0h-","type":"add-field","name":"Add Field"}'
    condition: attributes["level"] == "Critical"
    final: true
    data_types:
    - log
    statements: |-
      set(attributes["my_new_field"], "my new value")
      set(attributes["my_second_new_field"], "my second value")

All data items that pass through this processor, and where attributes["level"] is Critical, will have the two new fields with these exact values.

Options

Select a telemetry type

You can specify, log, metric, trace or all. It is specified using the interface, which generates a YAML list item for you under the data_types parameter. This defines the data item types against which the processor must operate. If data_types is not specified, the default value is all. It is optional.

It is defined in YAML as follows:

- name: multiprocessor
  type: sequence
  processors:
  - type: <processor type>
    data_types:
    - log

Condition

The condition parameter contains a conditional phrase of an OTTL statement. It restricts operation of the processor to only data items where the condition is met. Those data items that do not match the condition are passed without processing. You configure it in the interface and an OTTL condition is generated. It is optional.

Important: All conditions must be written on a single line in YAML. Multi-line conditions are not supported.

Comparison Operators

Operator	Name	Description	Example
`==`	Equal to	Returns `true` if both values are exactly the same	`attributes["status"] == "OK"`
`!=`	Not equal to	Returns `true` if the values are not the same	`attributes["level"] != "debug"`
`>`	Greater than	Returns `true` if the left value is greater than the right	`attributes["duration_ms"] > 1000`
`>=`	Greater than or equal	Returns `true` if the left value is greater than or equal to the right	`attributes["score"] >= 90`
`<`	Less than	Returns `true` if the left value is less than the right	`attributes["load"] < 0.75`
`<=`	Less than or equal	Returns `true` if the left value is less than or equal to the right	`attributes["retries"] <= 3`
`matches`	Regex match	Returns `true` if the string matches a regular expression (generates `IsMatch` function)	`IsMatch(attributes["name"], ".*\\.log$")`

Logical Operators

Important: Use lowercase and, or, not - uppercase operators will cause errors!

Operator	Description	Example
`and`	Both conditions must be true	`attributes["level"] == "ERROR" and attributes["status"] >= 500`
`or`	At least one condition must be true	`attributes["log_type"] == "TRAFFIC" or attributes["log_type"] == "THREAT"`
`not`	Negates the condition	`not regex_match(attributes["path"], "^/health")`

Functions

Function	Description	Example
`regex_match`	Returns `true` if string matches the pattern	`regex_match(attributes["message"], "ERROR\\|FATAL")`
`IsMatch`	Alternative regex function (UI generates this from “matches” operator)	`IsMatch(attributes["name"], ".*\\.log$")`

Field Existence Checks

Check	Description	Example
`!= nil`	Field exists (not null)	`attributes["user_id"] != nil`
`== nil`	Field doesn’t exist	`attributes["optional_field"] == nil`
`!= ""`	Field is not empty string	`attributes["message"] != ""`

Common Examples

- name: _multiprocessor
  type: sequence
  processors:
  - type: <processor type>
    # Simple equality check
    condition: attributes["request"]["path"] == "/json/view"
    
  - type: <processor type>
    # Multiple values with OR
    condition: attributes["log_type"] == "TRAFFIC" or attributes["log_type"] == "THREAT"
    
  - type: <processor type>
    # Excluding multiple values (NOT equal to multiple values)
    condition: attributes["log_type"] != "TRAFFIC" and attributes["log_type"] != "THREAT"
    
  - type: <processor type>
    # Complex condition with AND/OR/NOT
    condition: (attributes["level"] == "ERROR" or attributes["level"] == "FATAL") and attributes["env"] != "test"
    
  - type: <processor type>
    # Field existence and value check
    condition: attributes["user_id"] != nil and attributes["user_id"] != ""
    
  - type: <processor type>
    # Regex matching using regex_match
    condition: regex_match(attributes["path"], "^/api/") and not regex_match(attributes["path"], "^/api/health")
    
  - type: <processor type>
    # Regex matching using IsMatch
    condition: IsMatch(attributes["message"], "ERROR|WARNING") and attributes["env"] == "production"

Common Mistakes to Avoid

# WRONG - Cannot use OR/AND with values directly
condition: attributes["log_type"] != "TRAFFIC" OR "THREAT"

# CORRECT - Must repeat the full comparison
condition: attributes["log_type"] != "TRAFFIC" and attributes["log_type"] != "THREAT"

# WRONG - Uppercase operators
condition: attributes["status"] == "error" AND attributes["level"] == "critical"

# CORRECT - Lowercase operators
condition: attributes["status"] == "error" and attributes["level"] == "critical"

# WRONG - Multi-line conditions
condition: |
  attributes["level"] == "ERROR" and 
  attributes["status"] >= 500  

# CORRECT - Single line (even if long)
condition: attributes["level"] == "ERROR" and attributes["status"] >= 500

Fields

The Fields section defines the fields and values to be added. Click the + icon to add a field path segment, and specify the static value. To add a second field click +Add row.

Final

Determines whether successfully processed data items should continue through the remaining processors in the same processor stack. If final is set to true, data items output by this processor are not passed to subsequent processors within the node—they are instead emitted to downstream nodes in the pipeline (e.g., a destination). Failed items are always passed to the next processor, regardless of this setting.

The UI provides a slider to configure this setting. The default is false. It is defined in YAML as follows:

- name: multiprocessor
  type: sequence
  processors:
    - type: <processor type>
    final: true