Functions of variables

Operations with active lists and dictionaries

"active_list" and "active_list_dyn" functions

These functions allow you to receive information from an active list and dynamically generate a field name for an active list and key.

You must specify the parameters in the following sequence:

1. Name of the active list
2. Expression that returns the field name of the active list
3. One or more expressions whose results are used to generate the key

   Usage example	Result
   active_list('Test', to_lower('DeviceHostName'), to_lower(DeviceCustomString2), to_lower(DeviceCustomString1))	Gets the field value of the active list.

Use these functions to query the active list of the shared tenant from a variable. To do so, add the @Shared suffix after the name of the active list (case sensitive). For example, active_list('exampleActiveList@Shared', 'score', SourceAddress, SourceUserName).

"table_dict" function

Gets information about the value in the specified column of a dictionary of the table type.

You must specify the parameters in the following sequence:

1. Dictionary name
2. Dictionary column name
3. One or more expressions whose results are used to generate the dictionary row key.

   Usage example	Result
   table_dict('exampleTableDict', 'office', SourceUserName)	Gets data from the exampleTableDict dictionary from the row with the SourceUserName key in the office column.
   table_dict('exampleTableDict', 'office', SourceAddress, to_lower(SourceUserName))	Gets data from the exampleTableDict dictionary from a composite key string from the SourceAddress field value and the lowercase value of the SourceUserName field from the office column.

Use this function to access the dictionary of the shared tenant from a variable. To do so, add the @Shared suffix after the name of the active list (case sensitive). For example, table_dict('exampleTableDict@Shared', 'office', SourceUserName).

"dict" function

Gets information about the value in the specified column of a dictionary of the dictionary type.

You must specify the parameters in the following sequence:

1. Dictionary name
2. One or more expressions whose results are used to generate the dictionary row key.

   Usage example	Result
   dict('exampleDictionary', SourceAddress)	Gets data from exampleDictionary from the row with the SourceAddress key.
   dict('exampleDictionary', SourceAddress, to_lower(SourceUserName))	Gets data from the exampleDictionary from a composite key string from the SourceAddress field value and the lowercase value of the SourceUserName field.

Use this function to access the dictionary of the shared tenant from a variable. To do so, add the @Shared suffix after the name of the active list (case sensitive). For example, dict('exampleDictionary@Shared', SourceAddress).

Operations with context tables

"context_table" function

Returns the value of the specified field in the base type (for example, integer, array of integers).

You must specify the parameters in the following sequence:

1. Name of the context table. The name must be specified.
2. Expression that returns the field name of context table.
3. Expression that returns the name of key field 1 of the context table.
4. Expression that returns the value of key field 1 of the context table.

The function must contain at least 4 parameters.

"len" function

Returns the length of a string or array.

The function returns the length of the array if the passed array is of one of the following types:

• array of integers
• array of floats
• array of strings
• array of booleans

If an array of a different type is passed, the data of the array is cast to the string type, and the function returns the length of the resulting string.

"distinct_items" function

Returns a list of unique elements in an array.

The function returns the list of unique elements of the array if the passed array is of one of the following types:

• array of integers
• array of floats
• array of strings
• array of booleans

If an array of a different type is passed, the data of the array is cast to the string type, and the function returns a string consisting of the unique characters from the original string.

"sort_items" function

Returns a sorted list of array elements.

You must specify the parameters in the following sequence:

1. Expression that returns the object of the sorting
2. Sorting order Possible values: asc, desc. If the parameter is not specified, the default value is asc.

The function returns the list of sorted elements of the array if the passed array is of one of the following types:

• array of integers
• array of floats
• array of strings

For a boolean array, the function returns the list of array elements in the original order.

If an array of a different type is passed, the data of the array is cast to the string type, and the function returns a string of sorted characters.

"item" function

Returns the array element with the specified index or the character of a string with the specified index if an array of integers, floats, strings, or boolean values is passed.

You must specify the parameters in the following sequence:

1. Expression that returns the object of the indexing
2. Expression that returns the index of the element or character.

The function must contain at least 2 parameters.

The function returns the array element with the specified index or the string character with the specified index if the index falls within the range of the array and the passed array is of one of the following types:

• array of integers
• array of floats
• array of strings
• array of booleans

If an array of a different type is passed and the index falls within the range of the array, the data is cast to the string type, and the function returns the string character with the specified index. If an array of a different type is passed and the index is outside the range of the array, the function returns an empty string.

Operation with rows

"len" function

Returns the number of characters in a string. Supported for standard fields and extended event schema fields of the "string" type.

A string can be passed as a string, field name or variable.

"to_lower" function

Converts characters in a string to lowercase. Supported for standard fields and extended event schema fields of the "string" type.

A string can be passed as a string, field name or variable.

"to_upper" function

Converts characters in a string to uppercase. Supported for standard fields and extended event schema fields of the "string" type. A string can be passed as a string, field name or variable.

"append" function

Adds characters to the end of a string. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. Added string.

Strings can be passed as a string, field name or variable.

"prepend" function

Adds characters to the beginning of a string. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. Added string.

Strings can be passed as a string, field name or variable.

"substring" function

Returns a substring from a string. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. Substring start position (natural number or 0).
3. (Optional) substring end position.

Strings can be passed as a string, field name or variable. If the position number is greater than the original data string length, an empty string is returned.

"index_of" function

The "index_of" function returns the position of the first occurrence of a character or substring in a string; the first character in the string has index 0.

The function accepts the following parameters:

• As source data, an event field, another variable, or constant.
• Any expression out of those that are available in local variables.

To use this function, you must specify the parameters in the following order:

1. Character or substring whose position you want to find.
2. String to be searched.

"last_index_of" function

The "last_index_of" function returns the position of the last occurrence of a character or substring in a string; the first character in the string has index 0.

The function accepts the following parameters:

• As source data, an event field, another variable, or constant.
• Any expression out of those that are available in local variables.

To use this function, you must specify the parameters in the following order:

1. Character or substring whose position you want to find.
2. String to be searched.

"tr" function

Deletes the specified characters from the beginning and end of a string. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. (Optional) string that should be removed from the beginning and end of the original string.

Strings can be passed as a string, field name or variable. If you do not specify a string to be deleted, spaces will be removed from the beginning and end of the original string.

"replace" function

Replaces all occurrences of character sequence A in a string with character sequence B. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. Search string: sequence of characters to be replaced.
3. Replacement string: sequence of characters to replace the search string.

Strings can be passed as an expression.

"regexp_replace" function

Replaces a sequence of characters that match a regular expression with a sequence of characters and regular expression capturing groups. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. Search string: regular expression.
3. Replacement string: sequence of characters to replace the search string, and IDs of the regular expression capturing groups. A string can be passed as an expression.

Strings can be passed as a string, field name or variable. Unnamed capturing groups can be used.

In regular expressions used in variable functions, each backslash character must be additionally escaped. For example, ^example\\\\ must be used instead of the regular expression ^example\\.

"regexp_capture" function

Gets the result matching the regular expression condition from the original string. Supported for standard fields and extended event schema fields of the "string" type.

You must specify the parameters in the following sequence:

1. Original string.
2. Search string: regular expression.

Strings can be passed as a string, field name or variable. Unnamed capturing groups can be used.

In regular expressions used in variable functions, each backslash character must be additionally escaped. For example, ^example\\\\ must be used instead of the regular expression ^example\\.

Operations with timestamps

now function

Gets a timestamp in epoch format. Runs with no arguments.

"extract_from_timestamp" function

Gets atomic time representations (year, month, day, hour, minute, second, day of the week) from fields and variables with time in the epoch format.

The parameters must be specified in the following sequence:

1. Event field of the timestamp type, or variable.
2. Notation of the atomic time representation. This parameter is case sensitive.

   Possible variants of atomic time notation:

   • y refers to the year in number format.
   • M refers to the month in number notation.
   • d refers to the number of the month.
   • wd refers to the day of the week: Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday.
   • h refers to the hour in 24-hour format.
   • m refers to the minutes.
   • s refers to the seconds.
3. (optional) Time zone notation. If this parameter is not specified, the time is calculated in UTC format.

   Usage examples

   extract_from_timestamp(Timestamp, 'wd')

   extract_from_timestamp(Timestamp, 'h')

   extract_from_timestamp($otherVariable, 'h')

   extract_from_timestamp(Timestamp, 'h', 'Europe/Moscow')

"parse_timestamp" function

Converts the time from RFC3339 format (for example, "2022-05-24 00:00:00", "2022-05-24 00:00:00+0300) to epoch format.

"format_timestamp" function

Converts the time from epoch format to RFC3339 format.

The parameters must be specified in the following sequence:

1. Event field of the timestamp type, or variable.
2. Time format notation: RFC3339.
3. (optional) Time zone notation. If this parameter is not specified, the time is calculated in UTC format.

   Usage examples

   format_timestamp(Timestamp, 'RFC3339')

   format_timestamp($otherVariable, 'RFC3339')

   format_timestamp(Timestamp, 'RFC3339', 'Europe/Moscow')

"truncate_timestamp" function

Rounds the time in epoch format. After rounding, the time is returned in epoch format. Time is rounded down.

The parameters must be specified in the following sequence:

1. Event field of the timestamp type, or variable.
2. Rounding parameter:
   • 1s rounds to the nearest second.
   • 1m rounds to the nearest minute.
   • 1h rounds to the nearest hour.
   • 24h rounds to the nearest day.
3. (optional) Time zone notation. If this parameter is not specified, the time is calculated in UTC format.

   Usage examples	Examples of rounded values	Usage result
   truncate_timestamp(Timestamp, '1m')	1654631774175 (7 June 2022, 19:56:14.175)	1654631760000 (7 June 2022, 19:56:00)
   truncate_timestamp($otherVariable, '1h')	1654631774175 (7 June 2022, 19:56:14.175)	1654628400000 (7 June 2022, 19:00:00)
   truncate_timestamp(Timestamp, '24h', 'Europe/Moscow')	1654631774175 (7 June 2022, 19:56:14.175)	1654560000000 (7 June 2022, 0:00:00)

"time_diff" function

Gets the time interval between two timestamps in epoch format.

The parameters must be specified in the following sequence:

1. Interval end time. Event field of the timestamp type, or variable.
2. Interval start time. Event field of the timestamp type, or variable.
3. Time interval notation:
   • ms refers to milliseconds.
   • s refers to seconds.
   • m refers to minutes.
   • h refers to hours.
   • d refers to days.

   Usage examples

   time_diff(EndTime, StartTime, 's')

   time_diff($otherVariable, Timestamp, 'h')

   time_diff(Timestamp, DeviceReceiptTime, 'd')

Mathematical operations

These are comprised of basic mathematical operations and functions.

Basic mathematical operations

Supported for integer and float fields of the extended event schema.

Operations:

• Addition
• Subtraction
• Multiplication
• Division
• Modulo division

Parentheses determine the sequence of actions

Available arguments:

• Numeric event fields
• Numeric variables
• Real numbers

  When modulo dividing, only natural numbers can be used as arguments.

Usage constraints:

• Division by zero returns zero.
• Mathematical operations on a number and a strings return the number unchanged. For example, 1 + abc returns 1.
• Integers resulting from operations are returned without a dot.

  Usage examples (Type=3; otherVariable=2; Message=text)	Usage result
  Type + 1	4
  $otherVariable - Type	-1
  2 * 2.5	5
  2 / 0	0
  Type * Message	0
  (Type + 2) * 2	10
  Type % $otherVariable	1

"round" function

Rounds numbers. Supported for integer and float fields of the extended event schema.

Available arguments:

• Numeric event fields
• Numeric variables
• Numeric constants

  Usage examples (DeviceCustomFloatingPoint1=7.75; DeviceCustomFloatingPoint2=7.5 otherVariable=7.2)	Usage result
  round(DeviceCustomFloatingPoint1)	8
  round(DeviceCustomFloatingPoint2)	8
  round($otherVariable)	7

"ceil" function

Rounds up numbers. Supported for integer and float fields of the extended event schema.

Available arguments:

• Numeric event fields
• Numeric variables
• Numeric constants

  Usage examples (DeviceCustomFloatingPoint1=7.15; otherVariable=8.2)	Usage result
  ceil(DeviceCustomFloatingPoint1)	8
  ceil($otherVariable)	9

"floor" function

Rounds down numbers. Supported for integer and float fields of the extended event schema.

Available arguments:

• Numeric event fields
• Numeric variables
• Numeric constants

  Usage examples (DeviceCustomFloatingPoint1=7.15; otherVariable=8.2)	Usage result
  floor(DeviceCustomFloatingPoint1)	7
  floor($otherVariable)	8

"abs" function

Gets the modulus of a number. Supported for integer and float fields of the extended event schema.

Available arguments:

• Numeric event fields
• Numeric variables
• Numeric constants

  Usage examples (DeviceCustomNumber1=-7; otherVariable=-2)	Usage result
  abs(DeviceCustomFloatingPoint1)	7
  abs($otherVariable)	2

"pow" function

Exponentiates a number. Supported for integer and float fields of the extended event schema.

The parameters must be specified in the following sequence:

1. Base — real numbers.
2. Power — natural numbers.

Available arguments:

• Numeric event fields
• Numeric variables
• Numeric constants

  Usage examples

  pow(DeviceCustomNumber1, DeviceCustomNumber2)

  pow($otherVariable, DeviceCustomNumber1)

"str_join" function

Join multiple strings into one using a separator. Supported for integer and float fields of the extended event schema.

The parameters must be specified in the following sequence:

1. Separator. String.
2. String1, string2, stringN. At least 2 expressions.

   Usage examples	Usage result
   str_join('|', to_lower(Name), to_upper(Name), Name)	String.

"conditional" function

Get one value if a condition is met and another value if the condition is not met. Supported for integer and float fields of the extended event schema.

The parameters must be specified in the following sequence:

1. Condition. String. The syntax is similar to the conditions of the Where statement in SQL. You can use the functions of the KUMA variables and references to other variables in a condition.
2. The value if the condition is met. Expression.
3. The value if the condition is not met. Expression.

Supported operators:

• AND
• OR
• NOT
• =
• !=
• <
• <=
• >
• >=
• LIKE (RE2 regular expression is used, rather than an SQL expression)
• ILIKE (RE2 regular expression is used, rather than an SQL expression)
• BETWEEN
• IN
• IS NULL (check for an empty value, such as 0 or an empty string)

  Usage examples (the value depends on arguments 2 and 3)

  conditional('SourceUserName = \\'root\\' AND DestinationUserName = SourceUserName', 'match', 'no match')

  conditional(`DestinationUserName ILIKE 'svc_.*'`, 'match', 'no match')

  conditional(`DestinationUserName NOT LIKE 'svc_.*'`, 'match', 'no match')

Operations for extended event schema fields

For extended event schema fields of the "string" type, the following kinds of operations are supported:

• "len" function
• "to_lower" function
• "to_upper" function
• "append" function
• "prepend" function
• "substring" function
• "tr" function
• "replace" function
• "regexp_replace" function
• "regexp_capture" function

For extended event schema fields of the integer or float type, the following kinds of operations are supported:

• Basic mathematical operations:
• "round" function
• "ceil" function
• "floor" function
• "abs" function
• "pow" function
• "str_join" function
• "conditional" function

For extended event schema fields of the "array of integers", "array of floats", and "array of strings" types, KUMA supports the following functions:

• Get the i-th element of the array. Example: item(<type>.someStringArray).
• Get an array of values. Example: <type>.someStringArray. Returns ["string1", "string2", "string3"].
• Get the count of elements in an array. Example: len(<type>.someStringArray). Returns ["string1", "string2"].
• Gett unique elements from an array. Example: distinct_items(<type>.someStringArray).
• Generate a TSV string of array elements. Example: to_string(<type>.someStringArray).
• Sort the elements of the array. Example: sort_items(<type>.someStringArray).

  In the examples, instead of <type>, you must specify the array type: NA for an array of integers, FA for an array of floats, SA for an array of strings.

For fields of the "array of integers" and "array of floats" types, the following functions are supported:

• math_min — returns the minimum element of an array. Example: math_min(NA.NumberArray), math_min(FA.FloatArray)

• math_max — returns the maximum element of an array Example: math_max(NA.NumberArray), math_max(FA.FloatArray)

• math_avg — returns the average value of an array. Example: math_avg(NA.NumberArray), math_avg(FA.FloatArray)