Class: Lumberjack::RedisDevice

Inherits:
Device
  • Object
show all
Defined in:
lib/lumberjack_redis_device.rb

Overview

This Lumberjack device logs output to a redis list. The redis list will automatically truncate to a given size to prevent running out of memory on the server. This is not inteneded to be a scalable logging solution, but it can be useful as an additional logging tool to expose recent logs.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name:, redis:, limit: 10_000, ttl: nil) ⇒ RedisDevice

Create a device. The name will be used as the key for the log entris in redis.

The redis object can either be a ‘Redis` instance or a block that yields a `Redis` instance.

You can also specify a time to live in seconds (ttl) and set the limit for the size of the list.



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# File 'lib/lumberjack_redis_device.rb', line 21

def initialize(name:, redis:, limit: 10_000, ttl: nil)
  @name = name
  @redis = redis
  @ttl = ttl.to_i
  @limit = limit
end

Instance Attribute Details

#limit ⇒ Object (readonly)

Returns the value of attribute limit.



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# File 'lib/lumberjack_redis_device.rb', line 13

def limit
  @limit
end

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/lumberjack_redis_device.rb', line 13

def name
  @name
end

#ttl ⇒ Object (readonly)

Returns the value of attribute ttl.



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# File 'lib/lumberjack_redis_device.rb', line 13

def ttl
  @ttl
end

Instance Method Details

#datetime_format ⇒ Object 



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# File 'lib/lumberjack_redis_device.rb', line 46

def datetime_format
  @time_formatter.format if @time_formatter
end

#datetime_format=(format) ⇒ Object 



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# File 'lib/lumberjack_redis_device.rb', line 50

def datetime_format=(format)
  @time_formatter = Lumberjack::Formatter::DateTimeFormatter.new(format)
end

#read(count = limit) ⇒ Object

Read a set number of entries from the list. The result will be an array of Lumberjack::LogEntry objects.



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# File 'lib/lumberjack_redis_device.rb', line 41

def read(count = limit)
  docs = redis.lrange(name, 0, count - 1)
  docs.collect { |json| entry_from_json(json) }
end

#redis ⇒ Object 



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# File 'lib/lumberjack_redis_device.rb', line 54

def redis
  if @redis.is_a?(Proc)
    @redis.call
  else
    @redis
  end
end

#write(entry) ⇒ Object

Write an entry to the list in redis



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# File 'lib/lumberjack_redis_device.rb', line 29

def write(entry)
  data = entry_as_json(entry)
  json = MultiJson.dump(data)
  redis.multi do |transaction|
    transaction.lpush(name, json)
    transaction.ltrim(name, 0, limit - 1)
    transaction.expire(name, ttl) if ttl && ttl > 0
  end
end