Module: Once

Defined in:
lib/once.rb,
lib/once/version.rb

Overview

Usage:

  1. Connect to redis: Once.redis = Redis.new(…)

If you don’t specify the redis connection, we will assume the presence of a $redis global

  1. Use to wrap a call that you want done uniquely

Once.do(name: "sending_email", params: { email: "[email protected]" }, within: 1.hour) do
  .. stuff that should happen only once ..
end

The combination of the name and params makes the check unique. So typically it would be the command you’re executing, plus the params to that command

Constant Summary collapse

DEFAULT_TIME =

seconds

3600
VERSION = 
"0.1.0"

Class Method Summary collapse

Class Method Details

.do(name:, params:, within: DEFAULT_TIME, &block) ⇒ Object

Checks the given params to see if this is a unique string If we’ve seen it within the expiry period (default: 1.hour), then we will not execute the block

name: The name of the check, used as a namespace params: The params that will control whether or not the body executes



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# File 'lib/once.rb', line 36

def do(name:, params:, within: DEFAULT_TIME, &block)
  hash = Digest::MD5.hexdigest(params.inspect)
  redis_key = "uniquecheck:#{name}:#{hash}"

  if redis.set(redis_key, true, ex: within, nx: true)
    begin
      block.call
    rescue
      redis.expire(redis_key, 0)
      raise
    end
  end
end

.redis ⇒ Object 



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# File 'lib/once.rb', line 22

def redis
  @redis || $redis
end

.redis=(redis) ⇒ Object 



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# File 'lib/once.rb', line 26

def redis=(redis)
  @redis = redis
end