Class: RagRuby::Generators::Gemini

Inherits:
Base
  • Object
show all
Defined in:
lib/rag_ruby/generators/gemini.rb

Constant Summary collapse

ENDPOINT = 
"https://generativelanguage.googleapis.com/v1beta/models"

Instance Method Summary collapse

Constructor Details

#initialize(model: "gemini-2.0-flash", api_key: nil) ⇒ Gemini

Returns a new instance of Gemini.

Raises:

  • (ArgumentError) 


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# File 'lib/rag_ruby/generators/gemini.rb', line 12

def initialize(model: "gemini-2.0-flash", api_key: nil)
  @model = model
  @api_key = api_key || ENV["GEMINI_API_KEY"]
  raise ArgumentError, "Gemini API key is required (set GEMINI_API_KEY or pass api_key:)" unless @api_key
end

Instance Method Details

#generate(prompt:, system_prompt: nil, temperature: 0.7) ⇒ Object 



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# File 'lib/rag_ruby/generators/gemini.rb', line 18

def generate(prompt:, system_prompt: nil, temperature: 0.7)
  body = {
    contents: [{ parts: [{ text: prompt }] }],
    generationConfig: { temperature: temperature }
  }
  if system_prompt
    body[:systemInstruction] = { parts: [{ text: system_prompt }] }
  end

  request_with_retry do
    uri = URI.parse("#{ENDPOINT}/#{@model}:generateContent?key=#{@api_key}")
    http = Net::HTTP.new(uri.host, uri.port)
    http.use_ssl = true
    http.open_timeout = 30
    http.read_timeout = 120

    req = Net::HTTP::Post.new(uri)
    req["Content-Type"] = "application/json"
    req.body = JSON.generate(body)

    response = http.request(req)

    unless response.is_a?(Net::HTTPSuccess)
      raise RagRuby::Error, "Gemini API error (#{response.code}): #{response.body}"
    end

    data = JSON.parse(response.body)
    text = data.dig("candidates", 0, "content", "parts", 0, "text")
    raise RagRuby::Error, "Empty response from Gemini" if text.nil?
    usage = data["usageMetadata"] || {}

    {
      text: text,
      tokens_used: {
        prompt: usage["promptTokenCount"],
        completion: usage["candidatesTokenCount"]
      }
    }
  end
end