Add ollama_api_key support for remote Ollama endpoints

lib/ruby_llm/configuration.rb

@@ -25,6 +25,7 @@ class Configuration
                   :openrouter_api_key,
                   :xai_api_key,
                   :ollama_api_base,
+                  :ollama_api_key,
                   :gpustack_api_base,
                   :gpustack_api_key,
                   :mistral_api_key,

lib/ruby_llm/providers/ollama.rb

@@ -13,7 +13,9 @@ def api_base
       end
 
       def headers
-        {}
+        return {} unless @config.ollama_api_key
+
+        { 'Authorization' => "Bearer #{@config.ollama_api_key}" }
       end
 
       class << self

spec/ruby_llm/providers/ollama_spec.rb

@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe RubyLLM::Providers::Ollama do
+  include_context 'with configured RubyLLM'
+
+  describe '#headers' do
+    it 'returns empty headers when no API key is configured' do
+      RubyLLM.configure { |config| config.ollama_api_key = nil }
+      provider = described_class.new(RubyLLM.config)
+
+      expect(provider.headers).to eq({})
+    end
+
+    it 'returns Authorization header when API key is configured' do
+      RubyLLM.configure { |config| config.ollama_api_key = 'test-ollama-key' }
+      provider = described_class.new(RubyLLM.config)
+
+      expect(provider.headers).to eq({ 'Authorization' => 'Bearer test-ollama-key' })
+    end
+  end
+end

spec/support/rubyllm_configuration.rb

@@ -23,6 +23,7 @@
       config.mistral_api_key = ENV.fetch('MISTRAL_API_KEY', 'test')
       config.model_registry_class = 'Model'
       config.ollama_api_base = ENV.fetch('OLLAMA_API_BASE', 'http://localhost:11434/v1')
+      config.ollama_api_key = ENV.fetch('OLLAMA_API_KEY', nil)
       config.openai_api_key = ENV.fetch('OPENAI_API_KEY', 'test')
       config.openrouter_api_key = ENV.fetch('OPENROUTER_API_KEY', 'test')
       config.perplexity_api_key = ENV.fetch('PERPLEXITY_API_KEY', 'test')