Note: We've renamed this gem from Plunk to Peruse. You can find the old gem here.

Peruse

Human-friendly query language for Elasticsearch

About

Peruse is a ruby gem to take a human-friendly, one-line search command and translate it to full-fledged JSON to send to Elasticsearch. Currently it only supports a few commands, but the goal is to support a large subset of what Elasticsearch offers.

Installation

gem install peruse

Peruse uses Parslet to first parse your query, and then Elasticsearch's official ruby library to send it to Elasticsearch.

Usage

require 'peruse'

# 
# Configuration is required before using Peruse
# 
# Elasticsearch_options accepts the same params as Elasticsearch::Client
# from the elasticsearch-ruby library
Peruse.configure do |config|
  config.elasticsearch_options = { host: 'localhost' }
end

# Restrict timeframe to last 1 week and match documents with _type=syslog
# s = seconds
# m = minutes
# h = hours
# d = days
# w = weeks
# All times in Peruse are converted to UTC
Peruse.search 'last 1w AND _type = syslog'

# The ```window``` command can also be used to filter by time
Peruse.search 'window -2d to -1d'

# Peruse tries to parse the date with Chronic, so this works too. Note the
# double quotes around the time string. This is needed if it contains a space.
Peruse.search 'window "last monday" to "last thursday"'

# Of course, absolute dates are supported as well. Date format is American style
# e.g. MM/DD/YY
Peruse.search 'window 3/14/12 to 3/15/12'

# Use double quotes to wrap space-containing strings
Peruse.search 'http.header = "UserAgent: Mozilla/5.0"'

# Commands are joined using parenthesized booleans
Peruse.search '(last 1h AND severity = 5) OR (last 1w AND severity = 3)'

# "AND" is aliased to "and" and "&". Similarly, "OR" is aliased to "or" and "|".
# The following queries are identical to one above
Peruse.search '(last 1h and severity = 5) or (last 1w and severity = 3)'
Peruse.search '(last 1h & severity = 5) | (last 1w & severity = 3)'

# Use the NOT keyword to negate the following command or boolean chain
Peruse.search 'NOT message = Error'

# Like AND and OR, "NOT" is aliased to "not" and "~"
Peruse.search 'not message = Error'
Peruse.search '~ message = Error'

# Regexp is supported as well
Peruse.search 'http.headers = /.*User-Agent: Mozilla.*/ OR http.headers = /.*application\/json.*/'

Translation

Under the hood, Peruse takes your query and translates it to Elasticsearch-compatible JSON. For example,

last 24h & _type=syslog

gets translated to:

{
  "query": {
    "filtered": {
      "filter": {
        "and": [
          {
            "range": {
              "timestamp": {
                "gte": "2013-08-23T05:43:13.770Z",
                "lte": "2013-08-24T05:43:13.770Z"
              }
            }
          },
          {
            "query": {
              "query_string": {
                "query": "_type:syslog"
              }
            }
          }
        ]
      }
    }
  }
}

In general, commands are combined into a single filter using Elasticsearch's, and, or, and not filters.