Class: Tina4::GraphDatabase

Inherits:
Object
  • Object
show all
Defined in:
lib/tina4/graph.rb

Overview

The URL-selected graph factory — the GraphDatabase sibling of Database.

Constant Summary collapse

ENGINE_ADAPTERS =

engine -> { require:, class:, package:, install: }. Selected lazily so requiring tina4/graph pulls in NO engine driver.

ultipa wraps the OPTIONAL tina4-ultipa gem (a missing gem surfaces as the actionable install error). bolt (Neo4j/Memgraph) and arango are pure-Ruby over stdlib (+socket+ / Net::HTTP) — zero third-party gems, so their require always succeeds and the install line is never reached; it stays declared for a uniform registry shape.

{
  "ultipa" => {
    require: "tina4/drivers/ultipa_graph_driver",
    class: "Tina4::Drivers::UltipaGraphDriver",
    package: "tina4-ultipa",
    install: "gem install tina4-ultipa   # or add gem \"tina4-ultipa\" to your Gemfile",
  },
  "bolt" => {
    require: "tina4/drivers/bolt_graph_driver",
    class: "Tina4::Drivers::BoltGraphDriver",
    package: "tina4ruby (built-in, stdlib socket)",
    install: "no install needed — the Bolt driver ships with tina4ruby",
  },
  "arango" => {
    require: "tina4/drivers/arango_graph_driver",
    class: "Tina4::Drivers::ArangoGraphDriver",
    package: "tina4ruby (built-in, stdlib Net::HTTP)",
    install: "no install needed — the ArangoDB driver ships with tina4ruby",
  },
}

Class Method Summary collapse

Class Method Details

.create(url, username: "", password: "") ⇒ Object

Parse the URL, pick the engine adapter, connect lazily.

The engine driver is required only here (first use of that engine); if it is absent the error names the package and the install command.



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# File 'lib/tina4/graph.rb', line 295

def self.create(url, username: "", password: "")
  graph_url = GraphUrl.new(url)
  registration = ENGINE_ADAPTERS[graph_url.engine]
  if registration.nil?
    raise GraphError,
          "No graph adapter for engine '#{graph_url.engine}' yet " \
          "(scheme '#{graph_url.scheme}'). Available: " \
          "#{ENGINE_ADAPTERS.keys.sort.join(', ')}."
  end

  begin
    require registration[:require]
  rescue LoadError => e
    # The adapter file requires its driver gem at the top; a missing gem
    # surfaces here as an actionable install error, never a bare LoadError.
    raise GraphError,
          "The graph driver for '#{graph_url.engine}' is not installed " \
          "(#{registration[:package]}). Install it with:\n    #{registration[:install]}",
      cause: e
  end

  adapter_class = Object.const_get(registration[:class])
  adapter_class.new(graph_url, username: username, password: password)
end

.from_env(env_key: "TINA4_GRAPH_URL") ⇒ Object

Build from TINA4_GRAPH_URL (+ TINA4_GRAPH_USERNAME/_PASSWORD).



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# File 'lib/tina4/graph.rb', line 321

def self.from_env(env_key: "TINA4_GRAPH_URL")
  url = ENV[env_key]
  return nil if url.nil? || url.strip.empty?

  create(url,
         username: ENV["TINA4_GRAPH_USERNAME"].to_s,
         password: ENV["TINA4_GRAPH_PASSWORD"].to_s)
end