Module: Langchain::DependencyHelper

Included in:
LLM::Base, Processors::Base, Tool::Base, Vectorsearch::Base
Defined in:
lib/langchain/dependency_helper.rb

Defined Under Namespace

Classes: LoadError, VersionError

Instance Method Summary collapse

Instance Method Details

#depends_on(gem_name, req: true) ⇒ Boolean

This method requires and loads the given gem, and then checks to see if the version of the gem meets the requirements listed in ‘langchain.gemspec` This solution was built to avoid auto-loading every single gem in the Gemfile when the developer will mostly likely be only using a few of them.

Parameters:

  • gem_name (String) —

    The name of the gem to load

Returns:

  • (Boolean) —

    Whether or not the gem was loaded successfully

Raises:

  • (LoadError) —

    If the gem is not installed

  • (VersionError) —

    If the gem is installed, but the version does not meet the requirements



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# File 'lib/langchain/dependency_helper.rb', line 17

def depends_on(gem_name, req: true)
  gem(gem_name) # require the gem

  return(true) unless defined?(Bundler) # If we're in a non-bundler environment, we're no longer able to determine if we'll meet requirements

  gem_version = Gem.loaded_specs[gem_name].version
  gem_requirement = Bundler.load.dependencies.find { |g| g.name == gem_name }&.requirement

  raise LoadError unless gem_requirement

  unless gem_requirement.satisfied_by?(gem_version)
    raise VersionError, "The #{gem_name} gem is installed, but version #{gem_requirement} is required. You have #{gem_version}."
  end

  lib_name = gem_name if req == true
  lib_name = req if req.is_a?(String)

  require(lib_name) if lib_name

  true
rescue ::LoadError
  raise LoadError, "Could not load #{gem_name}. Please ensure that the #{gem_name} gem is installed."
end