class LittleGhost::Providers::Gemini

Connects a Model to Google’s Gemini generateContent API.

Requests send messages, Tool definitions, attachments, and model settings to the configured Google endpoint. The adapter reads its API key from trusted configuration, honors cancellation and deadlines, and emits LittleGhost StreamEvents. HTTP and response-shape failures become ProviderError subclasses. It uses the built-in HTTP client and does not require Google’s SDK.

Attributes

model [R]

Provider-owned model identifier.

Public Class Methods

new (api_key:, model:, base_url: DEFAULT_BASE_URL, open_timeout: 10, read_timeout: 120, max_response_bytes: Support::HTTPClient::DEFAULT_MAX_RESPONSE_BYTES, transport: nil, **)

Source

# File lib/little_ghost/providers/gemini.rb, line 30
def initialize(api_key:, model:, base_url: DEFAULT_BASE_URL, open_timeout: 10, read_timeout: 120,
  max_response_bytes: Support::HTTPClient::DEFAULT_MAX_RESPONSE_BYTES, transport: nil, **)
  raise CredentialError, "Gemini api_key is required" if api_key.to_s.empty?

  @api_key = api_key
  @model = model
  @transport = transport || Support::HTTPClient.new(base_url:, open_timeout:, read_timeout:, max_response_bytes:)
end

Creates a Gemini generateContent client for model.

request_options ()

Source

# File lib/little_ghost/providers/gemini.rb, line 22
def self.request_options = %i[max_response_bytes open_timeout read_timeout].freeze

Request policy supported by Gemini and Vertex AI HTTP clients.

Public Instance Methods

capabilities (metadata: {})

Source

# File lib/little_ghost/providers/gemini.rb, line 61
def capabilities(metadata: {})
  ModelCapabilities.new(native_structured_output: true, tools: true, tool_choice: true,
    supported_parameters: metadata[:supported_parameters])
end

Reports Tool and structured-output support from model metadata.

stream (request) { |event| ... }

Source

# File lib/little_ghost/providers/gemini.rb, line 40
def stream(request)
  return enum_for(__method__, request) unless block_given?

  parser = Support::SSEParser.new
  normalizer = Normalizer.new(model:)
  @transport.stream(
    path: endpoint,
    headers: request_headers(request),
    body: JSON.generate(request_body(request)),
    cancellation_token: request.cancellation_token,
    deadline: request.deadline
  ) do |chunk|
    parser.<<(chunk).each { |data| normalizer.consume(JSON.parse(data)).each { |event| yield event } }
  end
  parser.finish.each { |data| normalizer.consume(JSON.parse(data)).each { |event| yield event } }
  normalizer.finish.each { |event| yield event }
rescue JSON::ParserError => error
  raise ProtocolError, "Google returned invalid JSON: #{error.message}"
end

Streams normalized events for request.