# Configuring custom parsers Use the information on this page to configure custom [parsers](https://docs.fluentbit.io/manual/data-pipeline/parsers). {% hint style="info" %} To define a custom parser, add an entry to the [`parsers` section](https://docs.fluentbit.io/manual/administration/configuring-fluent-bit/yaml/parsers-section) of your YAML configuration file, or create a [standalone parser file](https://docs.fluentbit.io/manual/administration/configuring-fluent-bit/yaml/parsers-section#standalone-parsers-files). {% endhint %} ## Configuration parameters Custom parsers support the following configuration parameters: | Key | Description | Default | | ---------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | | `decode_field` | If the content can be decoded in a structured message, append the structured message (keys and values) to the original log message. Decoder types: `json`, `escaped`, `escaped_utf8`, `mysql_quoted`. The syntax is: `decode_field `. See [Decoders](https://docs.fluentbit.io/manual/data-pipeline/parsers/decoders) for additional information. | *none* | | `decode_field_as` | Any decoded content (unstructured or structured) will be replaced in the same key/value, and no extra keys are added. Decoder types: `json`, `escaped`, `escaped_utf8`, `mysql_quoted`. The syntax is: `decode_field_as `. See [Decoders](https://docs.fluentbit.io/manual/data-pipeline/parsers/decoders) for additional information. | *none* | | `format` | Specifies the format of the parser. Possible options: [`json`](https://docs.fluentbit.io/manual/data-pipeline/parsers/json), [`regex`](https://docs.fluentbit.io/manual/data-pipeline/parsers/regular-expression), [`ltsv`](https://docs.fluentbit.io/manual/data-pipeline/parsers/ltsv), or [`logfmt`](https://docs.fluentbit.io/manual/data-pipeline/parsers/logfmt). | *none* | | `logfmt_no_bare_keys` | If enabled, the `logfmt` parser rejects log entries where keys don't have associated values (bare keys). Only applies to the `logfmt` format. | `false` | | `name` | Sets the name of your parser. | *none* | | `regex` | Required for parsers with the `regex` format. Specifies the Ruby regular expression for parsing and composing the structured message. | *none* | | `skip_empty_values` | Specifies a boolean which determines if the parser should skip empty values. | `true` | | `time_format` | Specifies the format of the time field so it can be recognized and analyzed properly. Fluent Bit uses `strptime(3)` to parse time. See the [`strptime` documentation](https://linux.die.net/man/3/strptime) for available modifiers. The `%L` field descriptor is supported for fractional seconds. | *none* | | `time_keep` | If enabled, when a time key is recognized and parsed, the parser will keep the original time key. If disabled, the parser will drop the original time field. | `false` | | `time_key` | If the log entry provides a field with a timestamp, this option specifies the name of that field. | *none* | | `time_offset` | Specifies a fixed UTC time offset (such as `-0600` or `+0200`) for local dates. | *none* | | `time_strict` | If `true`, the parser is strict with the expected time format. If `false`, the parser is permissive with the format of the time. Set to `false` when the format expects a time fraction but the time to be parsed doesn't include it. | `true` | | `time_system_timezone` | If there is no time zone (`%z`) specified in the given `time_format`, enabling this option will make the parser detect and use the system's configured time zone. The configured time zone is detected from the [`TZ` environment variable](https://sourceware.org/glibc/manual/latest/html_node/TZ-Variable.html). | `false` | | `types` | Specifies the data type of a parsed field. The syntax is `types : : ...`. The supported types are `string` (default), `integer`, `bool`, `float`, `hex`. | *none* | ### Time resolution and fractional seconds Time resolution and its format supported are handled by using the [strftime(3)](https://man7.org/linux/man-pages/man3/strftime.3.html) `libc` system function. In addition, Fluent Bit extends its time resolution to support fractional seconds like `2017-05-17T15:44:31.187512963Z`. The `%L` format option for `time_format` is provided as a way to indicate that content must be interpreted as fractional seconds. {% hint style="info" %} The option `%L` is only valid when used after seconds (`%S`) or seconds since the epoch (`%s`). For example, `%S.%L` and `%s.%L` are valid strings. {% endhint %} ### Supported time zone abbreviations The following time zone abbreviations are supported. #### Universal time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | -------------------------- | | `GMT` | `+00:00` | `0` | no | Greenwich Mean Time | | `UTC` | `+00:00` | `0` | no | Coordinated Universal Time | | `Z` | `+00:00` | `0` | no | Zulu Time (UTC) | | `UT` | `+00:00` | `0` | no | Universal Time | #### North American time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | ------------------------------------------------------- | | `EST` | `-05:00` | `-18000` | no | Eastern Standard Time | | `EDT` | `-04:00` | `-14400` | yes | Eastern Daylight Time | | `CST` | `-06:00` | `-21600` | no | Central Standard Time (North America) | | `CDT` | `-05:00` | `-18000` | yes | Central Daylight Time (North America) | | `MST` | `-07:00` | `-25200` | no | Mountain Standard Time | | `MDT` | `-06:00` | `-21600` | yes | Mountain Daylight Time | | `PST` | `-08:00` | `-28800` | no | Pacific Standard Time | | `PDT` | `-07:00` | `-25200` | yes | Pacific Daylight Time | | `AKST` | `-09:00` | `-32400` | no | Alaska Standard Time | | `AKDT` | `-08:00` | `-28800` | yes | Alaska Daylight Time | | `HST` | `-10:00` | `-36000` | no | Hawaii Standard Time | | `HADT` | `-09:00` | `-32400` | yes | Hawaii-Aleutian Daylight Time (rarely used for Hawaii) | | `AST` | `-04:00` | `-14400` | no | Atlantic Standard Time (for example, Canada, Caribbean) | | `ADT` | `-03:00` | `-10800` | yes | Atlantic Daylight Time | | `NST` | `-03:30` | `-12600` | no | Newfoundland Standard Time | | `NDT` | `-02:30` | `-9000` | yes | Newfoundland Daylight Time | #### European time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | ---------------------------- | | `WET` | `+00:00` | `0` | no | Western European Time | | `WEST` | `+01:00` | `3600` | yes | Western European Summer Time | | `CET` | `+01:00` | `3600` | no | Central European Time | | `CEST` | `+02:00` | `7200` | yes | Central European Summer Time | | `EET` | `+02:00` | `7200` | no | Eastern European Time | | `EEST` | `+03:00` | `10800` | yes | Eastern European Summer Time | | `MSK` | `+03:00` | `10800` | no | Moscow Standard Time | #### South American time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | -------------------------------------------------------------- | | `ART` | `-03:00` | `-10800` | no | Argentina Time | | `BRT` | `-03:00` | `-10800` | no | Brazil Time (main population areas, can vary by region/DST) | | `BRST` | `-02:00` | `-7200` | yes | Brazil Summer Time (historical, not currently observed by all) | | `CLT` | `-04:00` | `-14400` | no | Chile Standard Time | | `CLST` | `-03:00` | `-10800` | yes | Chile Summer Time | #### Australasian and Oceania time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | -------------------------------- | | `AEST` | `+10:00` | `36000` | no | Australian Eastern Standard Time | | `AEDT` | `+11:00` | `39600` | yes | Australian Eastern Daylight Time | | `ACST` | `+09:30` | `34200` | no | Australian Central Standard Time | | `ACDT` | `+10:30` | `37800` | yes | Australian Central Daylight Time | | `AWST` | `+08:00` | `28800` | no | Australian Western Standard Time | | `NZST` | `+12:00` | `43200` | no | New Zealand Standard Time | | `NZDT` | `+13:00` | `46800` | yes | New Zealand Daylight Time | #### Asian time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | -------------------------------------------------- | | `JST` | `+09:00` | `32400` | no | Japan Standard Time | | `KST` | `+09:00` | `32400` | no | Korea Standard Time | | `SGT` | `+08:00` | `28800` | no | Singapore Time | | `IST` | `+05:30` | `19800` | no | India Standard Time | | `GST` | `+04:00` | `14400` | no | Gulf Standard Time (for example, UAE, Oman) | | `ICT` | `+07:00` | `25200` | no | Indochina Time (Thailand, Vietnam, Laos, Cambodia) | | `WIB` | `+07:00` | `25200` | no | Western Indonesian Time | | `WITA` | `+08:00` | `28800` | no | Central Indonesian Time | | `WIT` | `+09:00` | `32400` | no | Eastern Indonesian Time | | `MYT` | `+08:00` | `28800` | no | Malaysia Time | | `BDT` | `+06:00` | `21600` | no | Bangladesh Standard Time | | `NPT` | `+05:45` | `20700` | no | Nepal Time | #### African time zones | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | -------------------------- | | `WAT` | `+01:00` | `3600` | no | West Africa Time | | `CAT` | `+02:00` | `7200` | no | Central Africa Time | | `EAT` | `+03:00` | `10800` | no | East Africa Time | | `SAST` | `+02:00` | `7200` | no | South Africa Standard Time | #### Military time zones {% hint style="info" %} These are single-letter UTC offset designators. `J` (Juliet) represents local time and isn't included. `Z` represents Zulu Time, as listed in the [Universal time zones](#universal-time-zones) list. {% endhint %} | Abbreviation | UTC Offset (`HH:MM`) | Offset (seconds) | Is DST | Description | | ------------ | -------------------- | ---------------- | ------ | ---------------------------------------------------- | | `A` | `+01:00` | `3600` | no | Alpha Time Zone | | `B` | `+02:00` | `7200` | no | Bravo Time Zone | | `C` | `+03:00` | `10800` | no | Charlie Time Zone | | `D` | `+04:00` | `14400` | no | Delta Time Zone | | `E` | `+05:00` | `18000` | no | Echo Time Zone | | `F` | `+06:00` | `21600` | no | Foxtrot Time Zone | | `G` | `+07:00` | `25200` | no | Golf Time Zone | | `H` | `+08:00` | `28800` | no | Hotel Time Zone | | `I` | `+09:00` | `32400` | no | India Time Zone (military, not Indian Standard Time) | | `K` | `+10:00` | `36000` | no | Kilo Time Zone | | `L` | `+11:00` | `39600` | no | Lima Time Zone | | `M` | `+12:00` | `43200` | no | Mike Time Zone | | `N` | `-01:00` | `-3600` | no | November Time Zone | | `O` | `-02:00` | `-7200` | no | Oscar Time Zone | | `P` | `-03:00` | `-10800` | no | Papa Time Zone | | `Q` | `-04:00` | `-14400` | no | Quebec Time Zone | | `R` | `-05:00` | `-18000` | no | Romeo Time Zone | | `S` | `-06:00` | `-21600` | no | Sierra Time Zone | | `T` | `-07:00` | `-25200` | no | Tango Time Zone | | `U` | `-08:00` | `-28800` | no | Uniform Time Zone | | `V` | `-09:00` | `-32400` | no | Victor Time Zone | | `W` | `-10:00` | `-36000` | no | Whiskey Time Zone | | `X` | `-11:00` | `-43200` | no | X-ray Time Zone | | `Y` | `-12:00` | `-46800` | no | Yankee Time Zone |