Class: Dalli::ElastiCache

Inherits:
Object
  • Object
show all
Defined in:
lib/dalli/elasticache.rb,
lib/dalli/elasticache/version.rb

Overview

Dalli::Elasticache provides an interface for providing a configuration endpoint for a memcached cluster on ElasticCache and retrieving the list of addresses (hostname and port) for the individual nodes of that cluster.

This allows the caller to pass that server list to Dalli, which then distributes cached items consistently over the nodes.

Constant Summary collapse

DEFAULT_TIMEOUT = 
5
VERSION = 
'2.0.0'

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(config_endpoint, dalli_options = {}, timeout: DEFAULT_TIMEOUT) ⇒ ElastiCache

Creates a new Dalli::ElasticCache instance.

config_endpoint - a String containing the host and (optionally) port of the configuration endpoint for the cluster. If not specified the port will default to 11211. The host must be either a DNS name, an IPv4 address, or a bracketed IPv6 address. dalli_options - a set of options passed to the Dalli::Client that is returned by the client method. Otherwise unused. timeout: - connect and read timeout in seconds for auto-discovery TCP calls. Defaults to 5 seconds.



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# File 'lib/dalli/elasticache.rb', line 41

def initialize(config_endpoint, dalli_options = {}, timeout: DEFAULT_TIMEOUT)
  @timeout = timeout
  @endpoint = Dalli::Elasticache::AutoDiscovery::Endpoint.new(config_endpoint, timeout:)
  @options = dalli_options
end

Instance Attribute Details

#endpoint ⇒ Object (readonly)

Returns the value of attribute endpoint.



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# File 'lib/dalli/elasticache.rb', line 27

def endpoint
  @endpoint
end

#options ⇒ Object (readonly)

Returns the value of attribute options.



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# File 'lib/dalli/elasticache.rb', line 27

def options
  @options
end

Instance Method Details

#client ⇒ Object

Dalli::Client configured to connect to the cluster’s nodes



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# File 'lib/dalli/elasticache.rb', line 48

def client
  Dalli::Client.new(servers, options)
end

#engine_version ⇒ Object

The cache engine version of the cluster

Returns a string



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# File 'lib/dalli/elasticache.rb', line 62

def engine_version
  endpoint.engine_version
end

#refresh ⇒ Object

Clear all cached data from the cluster endpoint



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# File 'lib/dalli/elasticache.rb', line 73

def refresh
  config_endpoint = "#{endpoint.host}:#{endpoint.port}"
  @endpoint = Dalli::Elasticache::AutoDiscovery::Endpoint.new(config_endpoint, timeout: @timeout)

  self
end

#servers ⇒ Object

List of cluster server nodes with ip addresses and ports Always use host name instead of private elasticache IPs as internal IPs can change after a node is rebooted



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# File 'lib/dalli/elasticache.rb', line 68

def servers
  endpoint.config.nodes.map(&:to_s)
end

#version ⇒ Object

The number of times the cluster configuration has been changed

Returns an integer



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# File 'lib/dalli/elasticache.rb', line 55

def version
  endpoint.config.version
end