Functions Index A-Z

The following list describes the built-in functions that ship with Graylog. Additional third-party functions are available via plugins in the marketplace.

Built-in Function Description
abbreviate Abbreviates a string using ellipses.

array_contains

Checks if the specified element is contained in the array.

array_remove

Removes the specified element from the array.
base16_decode Base16 decoding of the string which returns lower-case letters.
base16_encode Standard case- insensitive hex encoding using a 16-character subset.
base32_decode Decodes a string using a 32-character subset.
base32_encode Encodes a string using a 32-character subset.
base32human_decode Decodes a string in human-readable format using a 32-character subset.
base32human_encode Encodes a string in human-readable format using a 32-character subset.
base64_decode Decodes a string using a 64-character subset.
base64_encode Decodes a string using a 64-character subset.
base64url_decode URL-safe decoding of a string using a 64-character subset.
base64url_encode URL-safe encoding of the string using a 64-character subset.
capitalize Capitalizes a string changing the first letter to title case.
cidr_match Checks whether the given IP matches a CIDR pattern.
clone_message Clones a message.
concat Concatenates two strings.
contains Checks if a string contains another string.
crc32 Returns the hex encoded CRC32 digest of the given string.
crc32c Returns the hex encoded CRC32C (RFC 3720, Section 12.1) digest of the given string.
create_message Creates a new message which will be evaluated by the entire processing pipeline.
days Creates a period with a specified number of days.
debug Prints the passed value as a string in the Graylog log.
drop_message This currently processed message will be removed from the processing pipeline after the rule finishes.
ends_with Checks if a string ends with a given suffix.
expand_syslog_priority Converts a syslog priority number to its level and facility.
expand_syslog_priority_as_string Converts a syslog priority number to its level and facility string representations.
first_non_null Returns first non null element found in value.
flatten_json Parses a string as a JSON tree while flattening all containers to a single level.
flex_parse_date Attempts to parse a date and time using the Natty date parser.
format_date Formats a date and time according to a given formatter pattern.
from_input Checks whether the current message was received by the given input.
grok Applies a Grok pattern to a string.
grok_exists Checks if the given Grok pattern exists.
has_field Checks whether the currently processed message contains the named field.
hours Creates a period with a specified number of hours.
is_boolean Checks whether a value is a boolean value (true or false).
is_collection Checks whether a value is an iterable collection.
is_date Checks whether a value is a date (of type DateTime).
is_double Checks whether a value is a floating point value (of type double).
is_ip Checks whether a value is an IP address (IPv4 or IPv6).
is_json Checks whether a value is a parsed JSON tree.
is_list Checks whether a value is an iterable list.
is_long Checks whether a value is an integer value (of type long).
is_map Checks whether a value is a map.
is_not_null Checks whether a value is not null.
is_null Checks whether a value is null.
is_number Checks whether a value is a numeric value (of type long or double).
is_period Checks whether a value is a time period (of type Period).
is_string Checks whether a value is a string.
is_url Checks whether a value is a parsed URL.
join Joins the elements of the provided array into a single String.
key_value Extracts key/value pairs from a string.
length Counts the characters or bytes in a string.
lookup Looks up a multi value in the named lookup table.
lookup_add_string_list Lookup table manipulation.

lookup_all

Looks up all provided values in the named lookup table, and returns all results as an array.
lookup_clear_key Lookup table manipulation.

lookup_has_value

Lookup table manipulation.
lookup_remove_string_list Lookup table manipulation.
lookup_set_string_list Lookup table manipulation.
lookup_set_value Lookup table manipulation.
lookup_string_list Lookup table manipulation.
lookup_string_list_contains Looks up a value in the string list referenced by the key in the named lookup table.
lookup_value Looks up a single value in the named lookup table.
lowercase Converts a string to lower case.
md5 Returns the hex encoded MD5 digest of the given string.
metric_counter_inc The counter metric name, will always be prefixed with 'org.graylog.rulemetrics.'
millis Creates a period with a specified number of millis.
minutes Creates a period with a specified number of minutes.
months Creates a period with a specified number of months.
murmur3_128 Returns the hex encoded MurmurHash3 (128-bit) digest of the given string.
murmur3_32 Returns the hex encoded MurmurHash3 (32-bit) digest of the given string.
now Returns the current date and time.
parse_date Parses a date and time from the given string according to a strict pattern.
parse_json Parses a string into a JSON tree.
parse_unix_milliseconds Attempts to parse a UNIX millisecond timestamp (milliseconds since 1970-01-01T00:00:00.000Z).
period Parses an ISO 8601 period from the specified string.
regex Matches a regular expression against a string with matcher groups.
regex_replace Matches a regular expression against a string and replace with string.
remove_field Removes the named field from the currently processed message.
remove_from_stream Removes the current message from the specified stream.
rename_field Renames a message field.
replace Replaces the first “max” or all occurrences of a string within another string
route_to_stream Assigns the current message to the specified stream.
seconds Creates a period with a specified number of seconds.
select_jsonpath Selects one or more named JSON Path expressions from a JSON tree.
set_field Sets the name field to the given value in the currently processed message.
set_fields Sets multiple fields to the given values in the currently processed message.
sha1 Returns the hex encoded SHA1 digest of the given string.
sha256 Returns the hex encoded SHA256 digest of the given string.
sha512 Returns the hex encoded SHA512 digest of the given string.
split Splits a string around matches of this pattern (Java syntax).
starts_with Checks if a string starts with a given prefix.

string_array_add

Adds the specified string (or string array) value to the supplied string array. Casts the input array and value/value array to strings.

string_entropy

Computes Shannon's entropy of the character distribution in the given string.

substring Returns a substring of value with the given start and end offsets.
swapcase Swaps the case of a string.
syslog_facility Converts a syslog facility number to its string representation.
syslog_level Converts a syslog level number to its string representation.
to_bool Converts the single parameter to a boolean value using its string value.
to_date Converts a type to a date.
to_double Converts the first parameter to a double floating point value.
to_ip Converts the given string to an IP object.
to_long Converts the first parameter to a long integer value.
to_map Converts a value to a map.
to_string Converts the first parameter to its string representation.
to_url Converts a value to a valid URL using its string representation.
traffic_accounting_size Calculates the current size of the message as used by the traffic accounting system.
uncapitalize Uncapitalizes a string changing the first letter to lower case.
uppercase Converts a string to upper case.
urldecode Decodes an application/x-www-form-urlencoded string using a specific encoding scheme.
urlencode Translates a string into application/x-www-form-urlencoded format using a specific encoding scheme.
weeks Creates a period with a specified number of weeks.
years Creates a period with a specified number of years.