Edge Delta Parse JSON Processor

The Edge Delta parse JSON processor parses a JSON field into structured data.

  7 minute read  

Overview

The parse JSON processor parses a JSON string into an object. You can specify which field to parse and where to place the generated object. The processor performs a conditional transformation based on whether the attributes field is a map or not. If attributes is already a map, the processor will merge the JSON-parsed body into it. If it’s not a map, the processor will replace it completely with the parsed body.

Configuration

Consider this log, which was JSON format before being ingested by the Edge Delta agent:

{
  "_type": "log",
  "timestamp": 1745310871164,
  "body": "{\"timestamp\": \"2025-04-22T08:34:30.147024Z\", \"level\": \"Notice\", \"msg\": \"processing completed with minor issues\", \"user\": {\"email\": \"jane.smith@exampleemail.com\", \"id\": \"6e1bba47-5734-4843-94d8-205a638ec703\", \"name\": \"fd487c15-7e23-493e-92db-762fe63cfbf2\"}, \"request\": {\"ip\": \"172.31.212.225\", \"method\": \"POST\", \"path\": \"/json/view\"}, \"status\": 204, \"response_time_ms\": 466}",
  "resource": {
...
  },
  "attributes": {}

The resource field has been redacted for brevity.

Note the escape characters that have been added by the agent.

This example parses the body and generates the object as an attribute:

This is the YAML version:

- name: Multi Processor
  type: sequence
  processors:
  - type: ottl_transform
    metadata: '{"id":"3MBjcOAJZpSM13rweE6Do","type":"parse-json","name":"Parse JSON"}'
    statements: |-
      merge_maps(attributes, ParseJSON(body), "upsert") where IsMap(attributes)
      set(attributes, ParseJSON(body)) where not IsMap(attributes)

This is the resulting output log:

{
  "_type": "log",
  "timestamp": 1745310871164,
  "body": "{\"timestamp\": \"2025-04-22T08:34:30.147024Z\", \"level\": \"Notice\", \"msg\": \"processing completed with minor issues\", \"user\": {\"email\": \"jane.smith@exampleemail.com\", \"id\": \"6e1bba47-5734-4843-94d8-205a638ec703\", \"name\": \"fd487c15-7e23-493e-92db-762fe63cfbf2\"}, \"request\": {\"ip\": \"172.31.212.225\", \"method\": \"POST\", \"path\": \"/json/view\"}, \"status\": 204, \"response_time_ms\": 466}",
  "resource": {
...
  },
  "attributes": {
    "level": "Notice",
    "msg": "processing completed with minor issues",
    "request": {
      "ip": "172.31.212.225",
      "method": "POST",
      "path": "/json/view"
    },
    "response_time_ms": 466,
    "status": 204,
    "timestamp": "2025-04-22T08:34:30.147024Z",
    "user": {
      "email": "jane.smith@exampleemail.com",
      "id": "6e1bba47-5734-4843-94d8-205a638ec703",
      "name": "fd487c15-7e23-493e-92db-762fe63cfbf2"
    }
  }
}

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

Parse from

Specify the field containing the JSON string data.

Assign to

Specify the field where you want the parsed object to be saved.

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

Keep original telemetry item

Controls whether the original, unmodified telemetry item is preserved after processing. If keep_item is set to true, the processor emits both:

  • The original telemetry item (e.g., a log), and
  • Any new item generated by the processor (e.g., a metric extracted from the log)

Both items are passed to the next processor in the stack unless final is also set.

Interaction with final

If final: true is enabled, any successfully processed data items, whether original, newly created, or both, exit the processor stack or node immediately. No subsequent processors within the same node are evaluated, although downstream processing elsewhere in the pipeline continues. This means:

  • If keep_item: true and final: true, both the original and processed items bypass the remaining processors in the current node and are forwarded to downstream nodes (such as destinations).
  • If keep_item: false and final: true, only the processed item continues beyond this processor, skipping subsequent processors in the stack, and the original item is discarded.

Note: If the data item fails to be processed, final has no effect, the item continues through the remaining processors in the node regardless of the keep_item setting.

The app provides a slider to configure keep_item. The default is false.

- name: ed_gateway_output_a3fa_multiprocessor
  type: sequence
  processors:
    - type: <processor_type>
      keep_item: true
      final: true

See Also