module DatastaxRails::Connection::ClassMethods
Constants
- DEFAULT_OPTIONS
Public Instance Methods
Establish a Cassandra connection to DSE. datastax.yml will be read and the current environment's settings passed to this method.
The following is an example production configuration document. Assume that your setup consists of three datacenters each with three servers and RF=3 (i.e., you're storing your data 9 times)
servers: ["10.1.2.5"] port: 9042 ssl: cert: config/datastax_rails.crt key: config/datastax_rails.key ca_cert: config/ca.crt keypass: changeme keyspace: "datastax_rails_production" strategy_class: "org.apache.cassandra.locator.NetworkTopologyStrategy" strategy_options: {"DS1": "3", "DS2": "3", "DS3": "3"} connection_options: timeout: 10 solr: port: 8983 path: /solr
The servers
entry should be a list of all seed nodes for servers you wish to connect to. DSR will automatically connect to all nodes in the cluster or in the datacenter if you are using multiple datacenters. You can safely just list all nodes in a particular datacenter if you would like.
The port to connect to, this port will be used for all nodes. Because the `system.peers` table does not contain the port that the nodes are listening on, the port must be the same for all nodes.
Since we're using the NetworkTopologyStrategy for our locator, it is important that you configure cassandra-topology.properties. See the DSE documentation at www.datastax.com for more information.
strategy_options lets us specify what our topology looks like. In this case, we have RF=3 in all three of our datacenters (DS1, DS2, and DS3).
connection_options are the options that are passed to the thrift layer for the connection to cassandra.
-
retries - Number of times a request will be retried. Should likely be the number of servers - 1. Defaults to 0.
-
server_retry_period - Amount of time to wait before retrying a down server. Defaults to 1.
-
server_max_requests - Number of requests to make to a server before moving to the next one (helps keep load balanced). Default to 500.
-
retry_overrides - Overrides retries option for individual exceptions.
-
connect_timeout - The connection timeout on the Thrift socket. Defaults to 0.1.
-
timeout - The timeout for the transport layer. Defaults to 1.
See solr_connection
for a description of the solr options in datastax.yml
# File lib/datastax_rails/connection.rb, line 77 def establish_connection(spec) DatastaxRails::Base.config = spec.with_indifferent_access spec.reverse_merge!(DEFAULT_OPTIONS) load_balancing_policy = DatastaxRails::LoadBalancing::Policies::StickyDcAwareRoundRobin.new(spec[:server_max_requests]) cluster_options = { hosts: spec[:servers], connection_timeout: spec[:connection_options][:timeout], timeout: spec[:connection_options][:timeout], load_balancing_policy: load_balancing_policy } if ssl_type ca_cert = Pathname.new(DatastaxRails::Base.config[:ssl][:ca_cert]) ca_cert = Rails.root.join(ca_cert) unless ca_cert.absolute? ssl_context = OpenSSL::SSL::SSLContext.new ssl_context.verify_mode = OpenSSL::SSL::VERIFY_PEER ssl_context.ca_file = ca_cert.to_s if ssl_type == :two_way_ssl cert = Pathname.new(DatastaxRails::Base.config[:ssl][:cert]) key = Pathname.new(DatastaxRails::Base.config[:ssl][:key]) pass = DatastaxRails::Base.config[:ssl][:keypass] cert = Rails.root.join(cert) unless cert.absolute? key = Rails.root.join(key) unless key.absolute? if pass ssl_context.key = OpenSSL::PKey::RSA.new(key.read, pass) else ssl_context.key = OpenSSL::PKey::RSA.new(key.read) end ssl_context.cert = OpenSSL::X509::Certificate.new(cert.read) end cluster_options[:ssl] = ssl_context end self.current_server = spec[:servers].first self.cluster = Cassandra.cluster(cluster_options) self.connection = cluster.connect(spec[:keyspace]) end
Similar to establish_connection
, this method creates a connection object for Solr. Since HTTP is stateless, this doesn't actually launch the connection, but it gets everything set up so that RSolr can do its work. It's important to note that unlike the cassandra connection which is global to all of DSR, each model will have its own solr_connection.
@return [RSolr::Client] RSolr client object
# File lib/datastax_rails/connection.rb, line 161 def establish_solr_connection opts = { url: "#{solr_base_url}/#{DatastaxRails::Base.connection.keyspace}.#{column_family}" } if ssl_type == :two_way_ssl ca_cert = Pathname.new(DatastaxRails::Base.config[:ssl][:ca_cert]) cert = Pathname.new(DatastaxRails::Base.config[:ssl][:cert]) key = Pathname.new(DatastaxRails::Base.config[:ssl][:key]) pass = DatastaxRails::Base.config[:ssl][:keypass] ca_cert = Rails.root.join(ca_cert) unless ca_cert.absolute? cert = Rails.root.join(cert) unless cert.absolute? key = Rails.root.join(key) unless key.absolute? opts[:ssl_cert_file] = cert.to_s opts[:ssl_key_file] = key.to_s opts[:ssl_key_pass] = pass if pass opts[:ssl_ca_file] = ca_cert.to_s RSolr::ClientCert.connect opts else RSolr.connect opts end end
rubocop:disable Style/RescueModifier
# File lib/datastax_rails/connection.rb, line 127 def reconnect connection.close rescue true self.connection = nil establish_connection(DatastaxRails::Base.config) end
Returns the base portion of the URL for connecting to SOLR based on the current Cassandra server.
@return [String] in the form of 'localhost:8983/solr'
# File lib/datastax_rails/connection.rb, line 136 def solr_base_url DatastaxRails::Base.establish_connection unless connection port = DatastaxRails::Base.config[:solr][:port] path = DatastaxRails::Base.config[:solr][:path] protocol = ssl_type ? 'https' : 'http' "#{protocol}://#{current_server}:#{port}#{path}" end
Wraps and caches a solr connection object
@params [Boolean] reconnect force a new connection @return [DatastaxRails::RSolrClientWrapper] a wrapped RSolr connection
# File lib/datastax_rails/connection.rb, line 148 def solr_connection(reconnect = false) if !@rsolr || reconnect @rsolr = DatastaxRails::RSolrClientWrapper.new(establish_solr_connection, self) end @rsolr end
# File lib/datastax_rails/connection.rb, line 114 def ssl_type return false unless DatastaxRails::Base.config && DatastaxRails::Base.config[:ssl] config = DatastaxRails::Base.config if config[:ssl][:key] && config[:ssl][:cert] :two_way_ssl elsif config[:ssl][:ca_cert] :one_way_ssl else false end end