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jc - JSON Convert Syslog RFC 5424 string streaming parser

This streaming parser outputs JSON Lines (cli) or returns an Iterable of Dictionaries (module)

This parser accepts a single syslog line string or multiple syslog lines separated by newlines. A warning message to STDERR will be printed if an unparsable line is found unless --quiet or quiet=True is used.

The timestamp_epoch calculated timestamp field is naive. (i.e. based on the local time of the system the parser is run on)

The timestamp_epoch_utc calculated timestamp field is timezone-aware and is only available if the timezone field is UTC.

Usage (cli):

$ echo <165>1 2003-08-24T05:14:15.000003-07:00 192.0... | jc --syslog-s

Usage (module):

import jc

result = jc.parse('syslog_s', syslog_command_output.splitlines())
for item in result:
    # do something


Blank values converted to null/None.

  "priority":                   integer,
  "version":                    integer,
  "timestamp":                  string,
  "timestamp_epoch":            integer,  # [0]
  "timestamp_epoch_utc":        integer,  # [1]
  "hostname":                   string,
  "appname":                    string,
  "proc_id":                    integer,
  "msg_id":                     string,
  "structured_data": [
      "identity":               string,
      "parameters": {
        "<key>":                string
  "message":                    string,
  "unparsable":                 string  # [2]

  # below object only exists if using -qq or ignore_exceptions=True
  "_jc_meta": {
    "success":      boolean,     # false if error parsing
    "error":        string,      # exists if "success" is false
    "line":         string       # exists if "success" is false

[0] naive timestamp if "timestamp" field is parsable, else null
[1] timezone aware timestamp available for UTC, else null
[2] this field exists if the syslog line is not parsable. The value
    is the original syslog line.


$ cat syslog.txt | jc --syslog-s -p

$ cat syslog.txt | jc --syslog-s -p -r


def parse(data: Iterable[str],
          raw: bool = False,
          quiet: bool = False,
          ignore_exceptions: bool = False) -> Union[Iterable[Dict], tuple]

Main text parsing generator function. Returns an iterable object.


data:              (iterable)  line-based text data to parse
                               (e.g. sys.stdin or str.splitlines())

raw:               (boolean)   unprocessed output if True
quiet:             (boolean)   suppress warning messages if True
ignore_exceptions: (boolean)   ignore parsing exceptions if True


Iterable of Dictionaries

Parser Information

Compatibility: linux, darwin, cygwin, win32, aix, freebsd

Source: jc/parsers/

Version 1.0 by Kelly Brazil (