length() is not working at all

[a0s]

I want to return length of symbol as metric's value

Source json:

{"symbol":["SLQD","SOLN","SHSP","SPAQ"]}

What i tried:

- name: data_loader_symbol_count
  type: object
  path: "{$.symbol[]}"
  help: Count of symbols
  values:
    value: "{$.length()}"

Result: msg="Failed to extract value for metric" path={$.length()} err="length() is not found" metric="Desc{fqName: \"data_loader_symbol_count_value\", help: \"Count of symbols\", constLabels: {}, variableLabels: []}"

- name: data_loader_symbol_count
  type: object
  path: "{$}"
  help: Count of symbols
  values:
    value: "{$.symbol.length()}"

Result: msg="Failed to extract value for metric" path={$.symbol.length()} err="length() is not found" metric="Desc{fqName: \"data_loader_symbol_count_value\", help: \"Count of symbols\", constLabels: {}, variableLabels: []}"

- name: data_loader_symbol_count
  type: object
  path: "{$.symbol.length()}"
  help: Count of symbols

Result: nothing and no error

- name: data_loader_symbol_count
  type: object
  path: "{$.symbol.length()}"
  help: Count of symbols
  values:
    value: "{$}"

Result: msg="Failed to extract json objects for metric" err="length() is not found" metric="Desc{fqName: \"data_loader_symbol_count_value\", help: \"Count of symbols\", constLabels: {}, variableLabels: []}"

Any help is very welcome!

[davinkevin]

Same thing for the sum() operator

[abhisheksurve45]

+1