Influxer

Influxer provides an ActiveRecord-style way to work with InfluxDB with many useful features, such as:

Installation

Adding to a gem:

# my-cool-gem.gemspec
Gem::Specification.new do |spec|
  # ...
  spec.add_dependency "influxer", ">= 1.2.0"
  # ...
end

Or adding to your project:

# Gemfile
gem "influxer", "~> 1.2"

Usage

Metrics classes

To query InfluxDB or write to it, you should define a metrics class first. Each metrics class represents a measurement/series (or multiple related measurements):

class VisitsMetrics < Influxer::Metrics
  # Define tags...
  tags :account_id, :page_id
  # ...and attributes
  attributes :user_id, :browser
end

Querying

Now you can use your metrics classes in a similar way to Active Record models to build queries. For example:

VisitsMetrics.select(:account_id, :user_id).where(page_id: /^home\/.*/)

Influxer provides special query methods for dealing with time series:

• Group by time: Metrics.time(:hour) => # select * ... group by time(1h).
• Select only points for the last hour/minute/whatever: Metrics.past(:day) => # select * ... where time > now() - 1d.
• Select only points since the specified time: Metrics.since(Time.utc(2014,12,31)) => # select * ... where time > 1419984000s.
• and more.

See our Wiki for more.

Scopes support

You can define scopes to re-use query conditions:

class Metrics < Influxer::Metrics
  tags :account_id
  attributes :value
  default_scope -> { time(:hour).limit(1000) }
  scope :unlimited, -> { limit(nil) }
  scope :by_account, ->(id) { where(account_id: id) if id.present? }
end
Metrics.by_account(1)
# => select * from "metrics" group by time(1h) where account_id=1 limit 1000
Metrics.unlimited.by_account(1).time(:week)
# => select * from "metrics" group by time(1w) where account_id=1

Active Record integration

You can association metrics with Active Record models:

class UserVisits < Influxer::Metrics
end
class User < ActiveRecord::Base
  has_metrics :visits
end
user = User.find(1)
user.visits.write(page_id: "home")
#=> < creates point {user_id: 1, page_id: 'home'} in 'user_visits' series >
user.visits.where(page_id: "home")
#=> select * from user_visits where page_id='home'

Find more on Wiki.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/palkan/influxer.

License

The gem is available as open source under the terms of the MIT License.