sdk-connection-ruby.rb

# Couchbase SDK connection singleton — Ruby
# Copy and adapt for your application.
#
# Dependencies:
#   gem install couchbase

require 'couchbase'

# --- Configuration ---
CB_HOST       = 'localhost'          # or 'cb.xxxxx.cloud.couchbase.com' for Capella
CB_USER       = 'app-service-user'
CB_PASSWORD   = 'AppSecret123!'
CB_BUCKET     = 'myapp'
CB_SCOPE      = '_default'
CB_COLLECTION = '_default'
# Use 'couchbases://' for TLS (required for Capella, recommended for production)
CB_SCHEME     = 'couchbase'

module CouchbaseConnection
  @cluster    = nil
  @collection = nil
  @mutex      = Mutex.new

  # Returns the singleton Collection, initializing the cluster on first call.
  def self.collection
    return @collection unless @collection.nil?

    @mutex.synchronize do
      return @collection unless @collection.nil?

      options = Couchbase::Options::Cluster.new
      options.authenticate(CB_USER, CB_PASSWORD)
      options.connect_timeout    = 10_000  # ms
      options.key_value_timeout  = 2_500   # ms
      options.query_timeout      = 75_000  # ms
      options.search_timeout     = 75_000  # ms

      @cluster    = Couchbase::Cluster.connect("#{CB_SCHEME}://#{CB_HOST}", options)
      @collection = @cluster.bucket(CB_BUCKET).scope(CB_SCOPE).collection(CB_COLLECTION)
    end

    @collection
  end

  # Returns the singleton Cluster (needed for queries).
  def self.cluster
    collection # ensures cluster is initialized
    @cluster
  end
end

# --- Usage example ---
col     = CouchbaseConnection.collection
cluster = CouchbaseConnection.cluster

# KV upsert
col.upsert('doc_1', { type: 'example', value: 42 })

# KV get
begin
  result = col.get('doc_1')
  puts result.content.inspect
rescue Couchbase::Error::DocumentNotFound
  puts 'Document not found'
end

# SQL++ query
result = cluster.query(
  'SELECT * FROM `myapp`._default._default WHERE type = $type LIMIT 5',
  Couchbase::Options::Query.new(named_parameters: { type: 'example' })
)
result.rows.each { |row| puts row.inspect }