node-grok

This library is inspired by logstash grok filter but it's not a port of it.

This is a templating library that helps reusing existing regular expressions and constructing new, more complex one. The primary goal was to help parsing and transforming plain text logs into JSON objects (one line => one object) based on provided template.

Install

Install locally: npm install node-grok.

Quick start

Following simple snippet

var p = '%{IP:client} \\[%{TIMESTAMP_ISO8601:timestamp}\\] "%{WORD:method} %{URIHOST:site}%{URIPATHPARAM:url}" %{INT:code} %{INT:request} %{INT:response} - %{NUMBER:took} \\[%{DATA:cache}\\] "%{DATA:mtag}" "%{DATA:agent}"';
var str = '65.19.138.33 [2015-05-13T08:04:43+10:00] "GET datasymphony.com.au/ru/feed/" 304 385 0 - 0.140 [HIT] "-" "Feedly/1.0 (+http://www.feedly.com/fetcher.html; like FeedFetcher-Google)"\n';

require('node-grok').loadDefault(function (patterns) {
    var pattern = patterns.createPattern(p);
    pattern.parse(str, function (err, obj) {
        console.log(obj);
    });
});

will transform string

65.19.138.33 [2015-05-13T08:04:43+10:00] "GET datasymphony.com.au/ru/feed/" 304 385 0 - 0.140 [HIT] "-" "Feedly/1.0 (+http://www.feedly.com/fetcher.html; like FeedFetcher-Google)"

into object

{
  "client": "65.19.138.33",
  "timestamp": "2015-05-13T08:04:43+10:00",
  "method": "GET",
  "site": "datasymphony.com.au",
  "url": "/ru/feed/",
  "code": "304",
  "request": "385",
  "response": "0",
  "took": "0.140",
  "cache": "HIT",
  "mtag": "-",
  "agent": "Feedly/1.0 (+http://www.feedly.com/fetcher.html; like FeedFetcher-Google)" 
}

API

loadDefault(callback, [loadModules]) - creates default pattern collection including all built-in patterns from ./patterns folder. By providing loadModules parameter you can limit number of loaded patterns: loadDefault(..., ['grok-patterns']);. Callback receives patterns collection filled in with default templates: function(patterns)
GrokCollection.createPattern(expression, [id]) - creates new pattern and adds it to the collection. Find out more about pattern syntax here and about regular expression syntax here
GrokCollection.load(filePath, next) - loads patterns from file
GrokPattern.parse(str, callback) - parses string using corresponding pattern. Callback function receives optional error and resulting object result: function(error, result)

License

ISC License (ISC)

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Kosta-Github/node-grok

node-grok

Install

Quick start

API

License