logstash-filter-date/pull/27

generated-date.asciidoc

date

The date filter is used for parsing dates from fields, and then using that date or timestamp as the logstash timestamp for the event.

For example, syslog events usually have timestamps like this:

    "Apr 17 09:32:01"

You would use the date format MMM dd HH:mm:ss to parse this.

The date filter is especially important for sorting events and for backfilling old data. If you don’t get the date correct in your event, then searching for them later will likely sort out of order.

In the absence of this filter, logstash will choose a timestamp based on the first time it sees the event (at input time), if the timestamp is not already set in the event. For example, with file input, the timestamp is set to the time of each read.

 

Synopsis

This plugin supports the following configuration options:

Required configuration options:

date {
}

Available configuration options:

Setting	Input type	Required	Default value
add_field	hash	No	{}
add_tag	array	No	[]
enable_metric	boolean	No	true
id	string	No
locale	string	No
match	array	No	[]
periodic_flush	boolean	No	false
remove_field	array	No	[]
remove_tag	array	No	[]
tag_on_failure	array	No	["_dateparsefailure"]
target	string	No	"@timestamp"
timezone	string	No

Details

 

add_field

• Value type is hash

• Default value is {}

If this filter is successful, add any arbitrary fields to this event. Field names can be dynamic and include parts of the event using the %{field}.

Example:

    filter {
      date {
        add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
      }
    }
[source,ruby]
    # You can also add multiple fields at once:
    filter {
      date {
        add_field => {
          "foo_%{somefield}" => "Hello world, from %{host}"
          "new_field" => "new_static_value"
        }
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would add field foo_hello if it is present, with the value above and the %{host} piece replaced with that value from the event. The second example would also add a hardcoded field.

add_tag

• Value type is array

• Default value is []

If this filter is successful, add arbitrary tags to the event. Tags can be dynamic and include parts of the event using the %{field} syntax.

Example:

    filter {
      date {
        add_tag => [ "foo_%{somefield}" ]
      }
    }
[source,ruby]
    # You can also add multiple tags at once:
    filter {
      date {
        add_tag => [ "foo_%{somefield}", "taggedy_tag"]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would add a tag foo_hello (and the second example would of course add a taggedy_tag tag).

enable_metric

• Value type is boolean

• Default value is true

id

• Value type is string

• There is no default value for this setting.

locale

• Value type is string

• There is no default value for this setting.

Specify a locale to be used for date parsing using either IETF-BCP47 or POSIX language tag. Simple examples are en,en-US for BCP47 or en_US for POSIX.

The locale is mostly necessary to be set for parsing month names (pattern with MMM) and weekday names (pattern with EEE).

If not specified, the platform default will be used but for non-english platform default an english parser will also be used as a fallback mechanism.

match

• Value type is array

• Default value is []

An array with field name first, and format patterns following, [ field, formats…​ ]

If your time field has multiple possible formats, you can do this:

    match => [ "logdate", "MMM dd YYY HH:mm:ss",
              "MMM  d YYY HH:mm:ss", "ISO8601" ]

The above will match a syslog (rfc3164) or iso8601 timestamp.

There are a few special exceptions. The following format literals exist to help you save time and ensure correctness of date parsing.

• ISO8601 - should parse any valid ISO8601 timestamp, such as 2011-04-19T03:44:01.103Z

• UNIX - will parse float or int value expressing unix time in seconds since epoch like 1326149001.132 as well as 1326149001

• UNIX_MS - will parse int value expressing unix time in milliseconds since epoch like 1366125117000

• TAI64N - will parse tai64n time values

For example, if you have a field logdate, with a value that looks like Aug 13 2010 00:03:44, you would use this configuration:

    filter {
      date {
        match => [ "logdate", "MMM dd YYYY HH:mm:ss" ]
      }
    }

If your field is nested in your structure, you can use the nested syntax [foo][bar] to match its value. For more information, please refer to [logstash-config-field-references]

More details on the syntax

The syntax used for parsing date and time text uses letters to indicate the kind of time value (month, minute, etc), and a repetition of letters to indicate the form of that value (2-digit month, full month name, etc).

Here’s what you can use to parse dates and times:

y	year yyyy full year number. Example: 2015. yy two-digit year. Example: 15 for the year 2015.
M	month of the year M minimal-digit month. Example: 1 for January and 12 for December. MM two-digit month. zero-padded if needed. Example: 01 for January and 12 for December MMM abbreviated month text. Example: Jan for January. Note: The language used depends on your locale. See the locale setting for how to change the language. MMMM full month text, Example: January. Note: The language used depends on your locale.
d	day of the month d minimal-digit day. Example: 1 for the 1st of the month. dd two-digit day, zero-padded if needed. Example: 01 for the 1st of the month.
H	hour of the day (24-hour clock) H minimal-digit hour. Example: 0 for midnight. HH two-digit hour, zero-padded if needed. Example: 00 for midnight.
m	minutes of the hour (60 minutes per hour) m minimal-digit minutes. Example: 0. mm two-digit minutes, zero-padded if needed. Example: 00.
s	seconds of the minute (60 seconds per minute) s minimal-digit seconds. Example: 0. ss two-digit seconds, zero-padded if needed. Example: 00.
S	fraction of a second Maximum precision is milliseconds (SSS). Beyond that, zeroes are appended. S tenths of a second. Example: 0 for a subsecond value 012 SS hundredths of a second. Example: 01 for a subsecond value 01 SSS thousandths of a second. Example: 012 for a subsecond value 012
Z	time zone offset or identity Z Timezone offset structured as HHmm (hour and minutes offset from Zulu/UTC). Example: -0700. ZZ Timezone offset structured as HH:mm (colon in between hour and minute offsets). Example: -07:00. ZZZ Timezone identity. Example: America/Los_Angeles. Note: Valid IDs are listed on the Joda.org available time zones page.
z	time zone names. Time zone names ('z') cannot be parsed.
w	week of the year w minimal-digit week. Example: 1. ww two-digit week, zero-padded if needed. Example: 01.
D	day of the year
e	day of the week (number)
E	day of the week (text) E, EE, EEE Abbreviated day of the week. Example: Mon, Tue, Wed, Thu, Fri, Sat, Sun. Note: The actual language of this will depend on your locale. EEEE The full text day of the week. Example: Monday, Tuesday, …​ Note: The actual language of this will depend on your locale.

For non-formatting syntax, you’ll need to put single-quote characters around the value. For example, if you were parsing ISO8601 time, "2015-01-01T01:12:23" that little "T" isn’t a valid time format, and you want to say "literally, a T", your format would be this: "yyyy-MM-dd’T’HH:mm:ss"

Other less common date units, such as era (G), century (C), am/pm (a), and # more, can be learned about on the joda-time documentation.

periodic_flush

• Value type is boolean

• Default value is false

Call the filter flush method at regular interval. Optional.

remove_field

• Value type is array

• Default value is []

If this filter is successful, remove arbitrary fields from this event. Fields names can be dynamic and include parts of the event using the %{field} Example:

    filter {
      date {
        remove_field => [ "foo_%{somefield}" ]
      }
    }
[source,ruby]
    # You can also remove multiple fields at once:
    filter {
      date {
        remove_field => [ "foo_%{somefield}", "my_extraneous_field" ]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would remove the field with name foo_hello if it is present. The second example would remove an additional, non-dynamic field.

remove_tag

• Value type is array

• Default value is []

If this filter is successful, remove arbitrary tags from the event. Tags can be dynamic and include parts of the event using the %{field} syntax.

Example:

    filter {
      date {
        remove_tag => [ "foo_%{somefield}" ]
      }
    }
[source,ruby]
    # You can also remove multiple tags at once:
    filter {
      date {
        remove_tag => [ "foo_%{somefield}", "sad_unwanted_tag"]
      }
    }

If the event has field "somefield" == "hello" this filter, on success, would remove the tag foo_hello if it is present. The second example would remove a sad, unwanted tag as well.

tag_on_failure

• Value type is array

• Default value is ["_dateparsefailure"]

Append values to the tags field when there has been no successful match

target

• Value type is string

• Default value is "@timestamp"

Store the matching timestamp into the given target field. If not provided, default to updating the @timestamp field of the event.

timezone

• Value type is string

• There is no default value for this setting.

Specify a time zone canonical ID to be used for date parsing. The valid IDs are listed on the Joda.org available time zones page. This is useful in case the time zone cannot be extracted from the value, and is not the platform default. If this is not specified the platform default will be used. Canonical ID is good as it takes care of daylight saving time for you For example, America/Los_Angeles or Europe/Paris are valid IDs. This field can be dynamic and include parts of the event using the %{field} syntax