Feature/yahoo finance (#123)

* Implement Yahoo Finance

* Added tests

* Updated hosting controller to check for managed app_mode instead of env_override

* Suggestions from CodeRabbit and Fixes on tests

* Remove Css changes

* Fix yahoo finance impl and i18n

* Updated view to use healthy method

* remove usage

* Updated env example

* keep usage on class just to keep same format

* Ci test

* Remove some useless validations

* Remove logs

* Linter fixes

* Broke this in my conflict merge

* Wrong indentation level

---------

Signed-off-by: Juan José Mata <juanjo.mata@gmail.com>
Co-authored-by: Juan José Mata <juanjo.mata@gmail.com>

.env.example

@@ -35,10 +35,15 @@ LANGFUSE_SECRET_KEY=
 # Get it here: https://twelvedata.com/
 TWELVE_DATA_API_KEY=
 
-# Optional: Twelve Data provider is the default for exchange rates and securities.
+# Optional: Provider selection for exchange rates and securities data
+# Options: twelve_data (default), yahoo_finance
 EXCHANGE_RATE_PROVIDER=twelve_data
 SECURITIES_PROVIDER=twelve_data
 
+# Alternative: Use Yahoo Finance as provider (free, no API key required)
+# EXCHANGE_RATE_PROVIDER=yahoo_finance
+# SECURITIES_PROVIDER=yahoo_finance
+
 # Custom port config
 # For users who have other applications listening at 3000, this allows them to set a value puma will listen to.
 PORT=3000

app/controllers/settings/hostings_controller.rb

@@ -12,6 +12,8 @@ class Settings::HostingsController < ApplicationController
     ]
     twelve_data_provider = Provider::Registry.get_provider(:twelve_data)
     @twelve_data_usage = twelve_data_provider&.usage
+
+    @yahoo_finance_provider = Provider::Registry.get_provider(:yahoo_finance)
   end
 
   def update

app/models/provider/registry.rb

@@ -75,6 +75,10 @@ class Provider::Registry
 
         Provider::Openai.new(access_token, uri_base: uri_base, model: model)
       end
+
+      def yahoo_finance
+        Provider::YahooFinance.new
+      end
   end
 
   def initialize(concept)
@@ -100,9 +104,9 @@ class Provider::Registry
     def available_providers
       case concept
       when :exchange_rates
-        %i[twelve_data]
+        %i[twelve_data yahoo_finance]
       when :securities
-        %i[twelve_data]
+        %i[twelve_data yahoo_finance]
       when :llm
         %i[openai]
       else

app/models/provider/yahoo_finance.rb

@@ -0,0 +1,603 @@
+class Provider::YahooFinance < Provider
+  include ExchangeRateConcept, SecurityConcept
+
+  # Subclass so errors caught in this provider are raised as Provider::YahooFinance::Error
+  Error = Class.new(Provider::Error)
+  InvalidSecurityPriceError = Class.new(Error)
+  RateLimitError = Class.new(Error)
+  InvalidSymbolError = Class.new(Error)
+  MarketClosedError = Class.new(Error)
+
+  # Cache duration for repeated requests (5 minutes)
+  CACHE_DURATION = 5.minutes
+
+  # Maximum lookback window for historical data (configurable)
+  MAX_LOOKBACK_WINDOW = 10.years
+
+  def initialize
+    # Yahoo Finance doesn't require an API key but we may want to add proxy support later
+    @cache_prefix = "yahoo_finance"
+  end
+
+  def healthy?
+    begin
+      # Test with a known stable ticker (Apple)
+      response = client.get("#{base_url}/v8/finance/chart/AAPL") do |req|
+        req.params["interval"] = "1d"
+        req.params["range"] = "1d"
+      end
+
+      data = JSON.parse(response.body)
+      result = data.dig("chart", "result")
+      health_status = result.present? && result.any?
+
+      health_status
+    rescue => e
+      false
+    end
+  end
+
+  def usage
+    # Yahoo Finance doesn't expose usage data, so we return a mock structure
+    with_provider_response do
+      usage_data = UsageData.new(
+        used: 0,
+        limit: 2000, # Estimated daily limit based on community knowledge
+        utilization: 0,
+        plan: "Free"
+      )
+
+      usage_data
+    end
+  end
+
+  # ================================
+  #          Exchange Rates
+  # ================================
+
+  def fetch_exchange_rate(from:, to:, date:)
+    with_provider_response do
+      # Return 1.0 if same currency
+      if from == to
+        Rate.new(date: date, from: from, to: to, rate: 1.0)
+      else
+        cache_key = "exchange_rate_#{from}_#{to}_#{date}"
+        if cached_result = get_cached_result(cache_key)
+          cached_result
+        else
+          # For a single date, we'll fetch a range and find the closest match
+          end_date = date
+          start_date = date - 10.days # Extended range for better coverage
+
+          rates_response = fetch_exchange_rates(
+            from: from,
+            to: to,
+            start_date: start_date,
+            end_date: end_date
+          )
+
+          raise Error, "Failed to fetch exchange rates: #{rates_response.error.message}" unless rates_response.success?
+
+          rates = rates_response.data
+          if rates.length == 1
+            rates.first
+          else
+            # Find the exact date or the closest previous date
+            target_rate = rates.find { |r| r.date == date } ||
+                         rates.select { |r| r.date <= date }.max_by(&:date)
+
+            raise Error, "No exchange rate found for #{from}/#{to} on or before #{date}" unless target_rate
+
+            cache_result(cache_key, target_rate)
+            target_rate
+          end
+        end
+      end
+    end
+  end
+
+  def fetch_exchange_rates(from:, to:, start_date:, end_date:)
+    with_provider_response do
+      validate_date_range!(start_date, end_date)
+      # Return 1.0 rates if same currency
+      if from == to
+        generate_same_currency_rates(from, to, start_date, end_date)
+      else
+        cache_key = "exchange_rates_#{from}_#{to}_#{start_date}_#{end_date}"
+        if cached_result = get_cached_result(cache_key)
+          cached_result
+        else
+          # Try both direct and inverse currency pairs
+          rates = fetch_currency_pair_data(from, to, start_date, end_date) ||
+                  fetch_inverse_currency_pair_data(from, to, start_date, end_date)
+
+          raise Error, "No chart data found for currency pair #{from}/#{to}" unless rates&.any?
+
+          cache_result(cache_key, rates)
+          rates
+        end
+      end
+    rescue JSON::ParserError => e
+      raise Error, "Invalid response format: #{e.message}"
+    end
+  end
+
+  # ================================
+  #           Securities
+  # ================================
+
+  def search_securities(symbol, country_code: nil, exchange_operating_mic: nil)
+    with_provider_response do
+      cache_key = "search_#{symbol}_#{country_code}_#{exchange_operating_mic}"
+      if cached_result = get_cached_result(cache_key)
+        return cached_result
+      end
+
+      response = client.get("#{base_url}/v1/finance/search") do |req|
+        req.params["q"] = symbol.strip.upcase
+        req.params["quotesCount"] = 25
+      end
+
+      data = JSON.parse(response.body)
+      quotes = data.dig("quotes") || []
+
+      securities = quotes.filter_map do |quote|
+        Security.new(
+          symbol: quote["symbol"],
+          name: quote["longname"] || quote["shortname"] || quote["symbol"],
+          logo_url: nil, # Yahoo search doesn't provide logos
+          exchange_operating_mic: map_exchange_mic(quote["exchange"]),
+          country_code: map_country_code(quote["exchDisp"])
+        )
+      end
+
+      cache_result(cache_key, securities)
+      securities
+    rescue JSON::ParserError => e
+      raise Error, "Invalid search response format: #{e.message}"
+    end
+  end
+
+  def fetch_security_info(symbol:, exchange_operating_mic:)
+    with_provider_response do
+      # Use quoteSummary endpoint which is more reliable
+      response = client.get("#{base_url}/v10/finance/quoteSummary/#{symbol}") do |req|
+        req.params["modules"] = "assetProfile,price,quoteType"
+      end
+
+      data = JSON.parse(response.body)
+      result = data.dig("quoteSummary", "result", 0)
+
+      raise Error, "No security info found for #{symbol}" unless result
+
+      asset_profile = result["assetProfile"] || {}
+      price_info = result["price"] || {}
+      quote_type = result["quoteType"] || {}
+
+      security_info = SecurityInfo.new(
+        symbol: symbol,
+        name: price_info["longName"] || price_info["shortName"] || quote_type["longName"] || quote_type["shortName"],
+        links: asset_profile["website"],
+        logo_url: nil, # Yahoo doesn't provide reliable logo URLs
+        description: asset_profile["longBusinessSummary"],
+        kind: map_security_type(quote_type["quoteType"]),
+        exchange_operating_mic: exchange_operating_mic
+      )
+
+      security_info
+    rescue JSON::ParserError => e
+      raise Error, "Invalid response format: #{e.message}"
+    end
+  end
+
+  def fetch_security_price(symbol:, exchange_operating_mic: nil, date:)
+    with_provider_response do
+      cache_key = "security_price_#{symbol}_#{exchange_operating_mic}_#{date}"
+      if cached_result = get_cached_result(cache_key)
+        return cached_result
+      end
+
+      # For a single date, we'll fetch a range and find the closest match
+      end_date = date
+      start_date = date - 10.days # Extended range for better coverage
+
+      prices_response = fetch_security_prices(
+        symbol: symbol,
+        exchange_operating_mic: exchange_operating_mic,
+        start_date: start_date,
+        end_date: end_date
+      )
+
+      raise Error, "Failed to fetch security prices: #{prices_response.error.message}" unless prices_response.success?
+
+      prices = prices_response.data
+      return prices.first if prices.length == 1
+
+      # Find the exact date or the closest previous date
+      target_price = prices.find { |p| p.date == date } ||
+                    prices.select { |p| p.date <= date }.max_by(&:date)
+
+      raise Error, "No price found for #{symbol} on or before #{date}" unless target_price
+
+      cache_result(cache_key, target_price)
+      target_price
+    end
+  end
+
+  def fetch_security_prices(symbol:, exchange_operating_mic: nil, start_date:, end_date:)
+    with_provider_response do
+      validate_date_params!(start_date, end_date)
+      # Convert dates to Unix timestamps using UTC to ensure consistent epoch boundaries across timezones
+      period1 = start_date.to_time.utc.to_i
+      period2 = end_date.end_of_day.to_time.utc.to_i
+
+      response = client.get("#{base_url}/v8/finance/chart/#{symbol}") do |req|
+        req.params["period1"] = period1
+        req.params["period2"] = period2
+        req.params["interval"] = "1d"
+        req.params["includeAdjustedClose"] = true
+      end
+
+      data = JSON.parse(response.body)
+      chart_data = data.dig("chart", "result", 0)
+
+      raise Error, "No chart data found for #{symbol}" unless chart_data
+
+      timestamps = chart_data.dig("timestamp") || []
+      quotes = chart_data.dig("indicators", "quote", 0) || {}
+      closes = quotes["close"] || []
+
+      # Get currency from metadata
+      currency = chart_data.dig("meta", "currency") || "USD"
+
+      prices = []
+      timestamps.each_with_index do |timestamp, index|
+        close_price = closes[index]
+        next if close_price.nil? # Skip days with no data (weekends, holidays)
+
+        prices << Price.new(
+          symbol: symbol,
+          date: Time.at(timestamp).to_date,
+          price: close_price.to_f,
+          currency: currency,
+          exchange_operating_mic: exchange_operating_mic
+        )
+      end
+
+      sorted_prices = prices.sort_by(&:date)
+      sorted_prices
+    rescue JSON::ParserError => e
+      raise Error, "Invalid response format: #{e.message}"
+    end
+  end
+
+  private
+
+    def base_url
+      ENV["YAHOO_FINANCE_URL"] || "https://query1.finance.yahoo.com"
+    end
+
+    # ================================
+    #           Validation
+    # ================================
+
+
+    def validate_date_range!(start_date, end_date)
+      raise Error, "Start date cannot be after end date" if start_date > end_date
+      raise Error, "Date range too large (max 5 years)" if end_date > start_date + 5.years
+    end
+
+    def validate_date_params!(start_date, end_date)
+      # Validate presence and coerce to dates
+      validated_start_date = validate_and_coerce_date!(start_date, "start_date")
+      validated_end_date = validate_and_coerce_date!(end_date, "end_date")
+
+      # Ensure start_date <= end_date
+      if validated_start_date > validated_end_date
+        error_msg = "Start date (#{validated_start_date}) cannot be after end date (#{validated_end_date})"
+        raise ArgumentError, error_msg
+      end
+
+      # Ensure end_date is not in the future
+      today = Date.current
+      if validated_end_date > today
+        error_msg = "End date (#{validated_end_date}) cannot be in the future"
+        raise ArgumentError, error_msg
+      end
+
+      # Optional: Enforce max lookback window (configurable via constant)
+      max_lookback = MAX_LOOKBACK_WINDOW.ago.to_date
+      if validated_start_date < max_lookback
+        error_msg = "Start date (#{validated_start_date}) exceeds maximum lookback window (#{max_lookback})"
+        raise ArgumentError, error_msg
+      end
+    end
+
+    def validate_and_coerce_date!(date_param, param_name)
+      # Check presence
+      if date_param.blank?
+        error_msg = "#{param_name} cannot be blank"
+        raise ArgumentError, error_msg
+      end
+
+      # Try to coerce to date
+      begin
+        if date_param.respond_to?(:to_date)
+          date_param.to_date
+        else
+          Date.parse(date_param.to_s)
+        end
+      rescue ArgumentError => e
+        error_msg = "Invalid #{param_name}: #{date_param} (#{e.message})"
+        raise ArgumentError, error_msg
+      end
+    end
+
+    # ================================
+    #           Caching
+    # ================================
+
+    def get_cached_result(key)
+      full_key = "#{@cache_prefix}_#{key}"
+      data = Rails.cache.read(full_key)
+      data
+    end
+
+    def cache_result(key, data)
+      full_key = "#{@cache_prefix}_#{key}"
+      Rails.cache.write(full_key, data, expires_in: CACHE_DURATION)
+    end
+
+
+
+    # ================================
+    #         Helper Methods
+    # ================================
+
+    def generate_same_currency_rates(from, to, start_date, end_date)
+      (start_date..end_date).map do |date|
+        Rate.new(date: date, from: from, to: to, rate: 1.0)
+      end
+    end
+
+    def fetch_currency_pair_data(from, to, start_date, end_date)
+      symbol = "#{from}#{to}=X"
+      fetch_chart_data(symbol, start_date, end_date) do |timestamp, close_rate|
+        Rate.new(
+          date: Time.at(timestamp).to_date,
+          from: from,
+          to: to,
+          rate: close_rate.to_f
+        )
+      end
+    end
+
+    def fetch_inverse_currency_pair_data(from, to, start_date, end_date)
+      symbol = "#{to}#{from}=X"
+      rates = fetch_chart_data(symbol, start_date, end_date) do |timestamp, close_rate|
+        Rate.new(
+          date: Time.at(timestamp).to_date,
+          from: from,
+          to: to,
+          rate: (1.0 / close_rate.to_f).round(8)
+        )
+      end
+
+      rates
+    end
+
+    def fetch_chart_data(symbol, start_date, end_date, &block)
+      period1 = start_date.to_time.utc.to_i
+      period2 = end_date.end_of_day.to_time.utc.to_i
+
+
+      begin
+        response = client.get("#{base_url}/v8/finance/chart/#{symbol}") do |req|
+          req.params["period1"] = period1
+          req.params["period2"] = period2
+          req.params["interval"] = "1d"
+          req.params["includeAdjustedClose"] = true
+        end
+
+        data = JSON.parse(response.body)
+
+        # Check for Yahoo Finance errors
+        if data.dig("chart", "error")
+          error_msg = data.dig("chart", "error", "description") || "Unknown Yahoo Finance error"
+          return nil
+        end
+
+        chart_data = data.dig("chart", "result", 0)
+        return nil unless chart_data
+
+        timestamps = chart_data.dig("timestamp") || []
+        quotes = chart_data.dig("indicators", "quote", 0) || {}
+        closes = quotes["close"] || []
+
+        results = []
+        timestamps.each_with_index do |timestamp, index|
+          close_value = closes[index]
+          next if close_value.nil? || close_value <= 0
+
+          results << block.call(timestamp, close_value)
+        end
+
+        results.sort_by(&:date)
+      rescue Faraday::Error => e
+        nil
+      end
+    end
+
+    def client
+      @client ||= Faraday.new(url: base_url) do |faraday|
+        faraday.request(:retry, {
+          max: 3,
+          interval: 0.1,
+          interval_randomness: 0.5,
+          backoff_factor: 2,
+          exceptions: [ Faraday::ConnectionFailed, Faraday::TimeoutError ]
+        })
+
+        faraday.request :json
+        faraday.response :raise_error
+
+        # Yahoo Finance requires common browser headers to avoid blocking
+        faraday.headers["User-Agent"] = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36"
+        faraday.headers["Accept"] = "application/json"
+        faraday.headers["Accept-Language"] = "en-US,en;q=0.9"
+        faraday.headers["Cache-Control"] = "no-cache"
+        faraday.headers["Pragma"] = "no-cache"
+
+        # Set reasonable timeouts
+        faraday.options.timeout = 10
+        faraday.options.open_timeout = 5
+      end
+    end
+
+    def map_country_code(exchange_name)
+      return nil if exchange_name.blank?
+
+      # Map common exchange names to country codes
+      case exchange_name.upcase.strip
+      when /NASDAQ|NYSE|AMEX|BATS|IEX/
+        "US"
+      when /TSX|TSXV|CSE/
+        "CA"
+      when /LSE|LONDON|AIM/
+        "GB"
+      when /TOKYO|TSE|NIKKEI|JASDAQ/
+        "JP"
+      when /ASX|AUSTRALIA/
+        "AU"
+      when /EURONEXT|PARIS|AMSTERDAM|BRUSSELS|LISBON/
+        case exchange_name.upcase
+        when /PARIS/ then "FR"
+        when /AMSTERDAM/ then "NL"
+        when /BRUSSELS/ then "BE"
+        when /LISBON/ then "PT"
+        else "FR" # Default to France for Euronext
+        end
+      when /FRANKFURT|XETRA|GETTEX/
+        "DE"
+      when /SIX|ZURICH/
+        "CH"
+      when /BME|MADRID/
+        "ES"
+      when /BORSA|MILAN/
+        "IT"
+      when /OSLO|OSE/
+        "NO"
+      when /STOCKHOLM|OMX/
+        "SE"
+      when /COPENHAGEN/
+        "DK"
+      when /HELSINKI/
+        "FI"
+      when /VIENNA/
+        "AT"
+      when /WARSAW|GPW/
+        "PL"
+      when /PRAGUE/
+        "CZ"
+      when /BUDAPEST/
+        "HU"
+      when /SHANGHAI|SHENZHEN/
+        "CN"
+      when /HONG\s*KONG|HKG/
+        "HK"
+      when /KOREA|KRX/
+        "KR"
+      when /SINGAPORE|SGX/
+        "SG"
+      when /MUMBAI|NSE|BSE/
+        "IN"
+      when /SAO\s*PAULO|BOVESPA/
+        "BR"
+      when /MEXICO|BMV/
+        "MX"
+      when /JSE|JOHANNESBURG/
+        "ZA"
+      else
+        nil
+      end
+    end
+
+    def map_exchange_mic(exchange_code)
+      return nil if exchange_code.blank?
+
+      # Map Yahoo exchange codes to MIC codes
+      case exchange_code.upcase.strip
+      when "NMS"
+        "XNAS" # NASDAQ Global Select
+      when "NGM"
+        "XNAS" # NASDAQ Global Market
+      when "NCM"
+        "XNAS" # NASDAQ Capital Market
+      when "NYQ"
+        "XNYS" # NYSE
+      when "PCX", "PSX"
+        "ARCX" # NYSE Arca
+      when "ASE", "AMX"
+        "XASE" # NYSE American
+      when "YHD"
+        "XNAS" # Yahoo default, assume NASDAQ
+      when "TSE", "TOR"
+        "XTSE" # Toronto Stock Exchange
+      when "CVE"
+        "XTSX" # TSX Venture Exchange
+      when "LSE", "LON"
+        "XLON" # London Stock Exchange
+      when "FRA"
+        "XFRA" # Frankfurt Stock Exchange
+      when "PAR"
+        "XPAR" # Euronext Paris
+      when "AMS"
+        "XAMS" # Euronext Amsterdam
+      when "BRU"
+        "XBRU" # Euronext Brussels
+      when "SWX"
+        "XSWX" # SIX Swiss Exchange
+      when "HKG"
+        "XHKG" # Hong Kong Stock Exchange
+      when "TYO"
+        "XJPX" # Japan Exchange Group
+      when "ASX"
+        "XASX" # Australian Securities Exchange
+      else
+        exchange_code.upcase
+      end
+    end
+
+    def map_security_type(quote_type)
+      case quote_type&.downcase
+      when "equity"
+        "common stock"
+      when "etf"
+        "etf"
+      when "mutualfund"
+        "mutual fund"
+      when "index"
+        "index"
+      else
+        quote_type&.downcase
+      end
+    end
+
+    # Override default error transformer to handle Yahoo Finance specific errors
+    def default_error_transformer(error)
+      case error
+      when Faraday::TooManyRequestsError
+        RateLimitError.new("Yahoo Finance rate limit exceeded", details: error.response&.dig(:body))
+      when Faraday::Error
+        Error.new(
+          error.message,
+          details: error.response&.dig(:body)
+        )
+      when Error
+        # Already a Yahoo Finance error, return as is
+        error
+      else
+        Error.new(error.message)
+      end
+    end
+end

app/views/settings/hostings/_yahoo_finance_settings.html.erb

@@ -0,0 +1,37 @@
+<div class="space-y-4">
+  <div>
+    <h2 class="font-medium mb-1"><%= t(".title") %></h2>
+    <p class="text-secondary text-sm mb-4"><%= t(".description") %></p>
+  </div>
+  <% if @yahoo_finance_provider&.healthy? %>
+    <div class="space-y-4">
+      <div class="flex items-center space-x-3">
+        <div class="w-3 h-3 bg-green-500 rounded-full"></div>
+        <p class="text-sm text-secondary">
+          <%= t(".status_active") %>
+        </p>
+      </div>
+    </div>
+  <% else %>
+    <div class="space-y-4">
+      <div class="flex items-center space-x-3">
+        <div class="w-3 h-3 bg-red-500 rounded-full"></div>
+        <p class="text-sm text-secondary">
+          <%= t(".status_inactive") %>
+        </p>
+      </div>
+      <div class="bg-red-50 border border-red-200 rounded-lg p-3">
+        <div class="flex">
+          <div class="ml-3">
+            <h3 class="text-sm font-medium text-red-800">
+              <%= t(".connection_failed") %>
+            </h3>
+            <div class="mt-2 text-sm text-red-700">
+              <p><%= t(".troubleshooting") %></p>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  <% end %>
+</div>

app/views/settings/hostings/show.html.erb

@@ -1,17 +1,19 @@
 <%= content_for :page_title, t(".title") %>
-
 <%= settings_section title: t(".general") do %>
     <div class="space-y-6">
     <%= render "settings/hostings/openai_settings" %>
     <%= render "settings/hostings/brand_fetch_settings" %>
+  </div>
+<% end %>
+<%= settings_section title: t(".financial_data_providers") do %>
+  <div class="space-y-6">
+    <%= render "settings/hostings/yahoo_finance_settings" %>
     <%= render "settings/hostings/twelve_data_settings" %>
   </div>
 <% end %>
-
 <%= settings_section title: t(".invites") do %>
   <%= render "settings/hostings/invite_code_settings" %>
 <% end %>
-
 <%= settings_section title: t(".danger_zone") do %>
   <%= render "settings/hostings/danger_zone_settings" %>
 <% end %>

config/locales/views/settings/hostings/en.yml

@@ -15,8 +15,9 @@ en:
           closed: Closed
           invite_only: Invite-only
       show:
-        general: External Services
-        invites: Onboarding
+        general: General Settings
+        financial_data_providers: Financial Data Providers
+        invites: Invite Codes
         title: Self-Hosting
         danger_zone: Danger Zone
         clear_cache: Clear data cache
@@ -28,7 +29,7 @@ en:
         description: Enter the Client ID provided by Brand Fetch
         label: Client ID
         placeholder: Enter your Client ID here
-        title: Brand Fetch
+        title: Brand Fetch Settings
       openai_settings:
         description: Enter the access token and optionally configure a custom OpenAI-compatible provider
         env_configured_message: Successfully configured through environment variables.
@@ -39,6 +40,13 @@ en:
         model_label: Model (Optional)
         model_placeholder: "gpt-4.1 (default)"
         title: OpenAI
+      yahoo_finance_settings:
+        title: Yahoo Finance
+        description: Yahoo Finance provides free access to stock prices, exchange rates, and financial data without requiring an API key.
+        status_active: Yahoo Finance is active and working
+        status_inactive: Yahoo Finance connection failed
+        connection_failed: Unable to connect to Yahoo Finance
+        troubleshooting: Check your internet connection and firewall settings. Yahoo Finance may be temporarily unavailable.
       twelve_data_settings:
         api_calls_used: "%{used} / %{limit} API daily calls used (%{percentage})"
         description: Enter the API key provided by Twelve Data

config/locales/views/settings/hostings/nb.yml

@@ -16,7 +16,8 @@ nb:
           invite_only: Kun invitasjon
       show:
         general: Generelle innstillinger
-        invites: Onboarding
+        financial_data_providers: Finansdata-leverandører
+        invites: Invitasjonskoder
         title: Selvhosting
         danger_zone: Fareområde
         clear_cache: Tøm cache
@@ -31,3 +32,11 @@ nb:
       clear_cache:
         cache_cleared: Cachen er tømt. Dette kan ta noen øyeblikk å fullføre.
       not_authorized: Du er ikke autorisert til å utføre denne handlingen
+      yahoo_finance_settings:
+        title: Yahoo Finance
+        description: Yahoo Finance gir gratis tilgang til aksjekurser, valutakurser og finansdata uten å kreve en API-nøkkel.
+        status_active: Yahoo Finance er aktiv og fungerer
+        status_inactive: Yahoo Finance-tilkobling feilet
+        connection_failed: Kunne ikke koble til Yahoo Finance
+        troubleshooting: Sjekk internettilkoblingen og brannmurinnstillingene. Yahoo Finance kan være midlertidig utilgjengelig.
+

config/locales/views/settings/hostings/tr.yml

@@ -15,7 +15,8 @@ tr:
           invite_only: Davet ile
       show:
         general: Genel Ayarlar
-        invites: Onboarding
+        financial_data_providers: Finansal Veri Sağlayıcıları
+        invites: Davet Kodları
         title: Kendi Sunucunda Barındırma
         danger_zone: Tehlikeli Bölge
         clear_cache: Veri önbelleğini temizle
@@ -37,3 +38,10 @@ tr:
       clear_cache:
         cache_cleared: Veri önbelleği temizlendi. Bu işlemin tamamlanması birkaç dakika sürebilir.
       not_authorized: Bu işlemi gerçekleştirmek için yetkiniz yok
+      yahoo_finance_settings:
+        title: Yahoo Finance
+        description: Yahoo Finance, API anahtarı gerektirmeden hisse senedi fiyatları, döviz kurları ve finansal verilere ücretsiz erişim sağlar.
+        status_active: Yahoo Finance aktif ve çalışıyor
+        status_inactive: Yahoo Finance bağlantısı başarısız
+        connection_failed: Yahoo Finance'e bağlanılamıyor
+        troubleshooting: İnternet bağlantınızı ve güvenlik duvarı ayarlarınızı kontrol edin. Yahoo Finance geçici olarak kullanılamayabilir.

test/controllers/settings/hostings_controller_test.rb

@@ -9,14 +9,17 @@ class Settings::HostingsControllerTest < ActionDispatch::IntegrationTest
 
     @provider = mock
     Provider::Registry.stubs(:get_provider).with(:twelve_data).returns(@provider)
-    @usage_response = provider_success_response(
+
+    @provider.stubs(:healthy?).returns(true)
+    Provider::Registry.stubs(:get_provider).with(:yahoo_finance).returns(@provider)
+    @provider.stubs(:usage).returns(provider_success_response(
       OpenStruct.new(
         used: 10,
         limit: 100,
         utilization: 10,
         plan: "free",
       )
-    )
+    ))
   end
 
   test "cannot edit when self hosting is disabled" do

test/models/provider/yahoo_finance_test.rb

@@ -0,0 +1,218 @@
+require "test_helper"
+
+class Provider::YahooFinanceTest < ActiveSupport::TestCase
+  setup do
+    @provider = Provider::YahooFinance.new
+  end
+
+  # ================================
+  #        Health Check Tests
+  # ================================
+
+  test "healthy? returns true when API is working" do
+    # Mock successful response
+    mock_response = mock
+    mock_response.stubs(:body).returns('{"chart":{"result":[{"meta":{"symbol":"AAPL"}}]}}')
+
+    @provider.stubs(:client).returns(mock_client = mock)
+    mock_client.stubs(:get).returns(mock_response)
+
+    assert @provider.healthy?
+  end
+
+  test "healthy? returns false when API fails" do
+    # Mock failed response
+    @provider.stubs(:client).returns(mock_client = mock)
+    mock_client.stubs(:get).raises(Faraday::Error.new("Connection failed"))
+
+    assert_not @provider.healthy?
+  end
+
+  # ================================
+  #      Exchange Rate Tests
+  # ================================
+
+  test "fetch_exchange_rate returns 1.0 for same currency" do
+    date = Date.parse("2024-01-15")
+    response = @provider.fetch_exchange_rate(from: "USD", to: "USD", date: date)
+
+    assert response.success?
+    rate = response.data
+    assert_equal 1.0, rate.rate
+    assert_equal "USD", rate.from
+    assert_equal "USD", rate.to
+    assert_equal date, rate.date
+  end
+
+  test "fetch_exchange_rate handles invalid currency codes" do
+    date = Date.parse("2024-01-15")
+
+    # With validation removed, invalid currencies will result in API errors
+    response = @provider.fetch_exchange_rate(from: "INVALID", to: "USD", date: date)
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+
+    response = @provider.fetch_exchange_rate(from: "USD", to: "INVALID", date: date)
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+
+    response = @provider.fetch_exchange_rate(from: "", to: "USD", date: date)
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+  end
+
+  test "fetch_exchange_rates returns same currency rates" do
+    start_date = Date.parse("2024-01-10")
+    end_date = Date.parse("2024-01-12")
+    response = @provider.fetch_exchange_rates(from: "USD", to: "USD", start_date: start_date, end_date: end_date)
+
+    assert response.success?
+    rates = response.data
+    expected_dates = (start_date..end_date).to_a
+    assert_equal expected_dates.length, rates.length
+    assert rates.all? { |r| r.rate == 1.0 }
+    assert rates.all? { |r| r.from == "USD" }
+    assert rates.all? { |r| r.to == "USD" }
+  end
+
+  test "fetch_exchange_rates validates date range" do
+    response = @provider.fetch_exchange_rates(from: "USD", to: "EUR", start_date: Date.current, end_date: Date.current - 1.day)
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+
+    response = @provider.fetch_exchange_rates(from: "USD", to: "EUR", start_date: Date.current - 6.years, end_date: Date.current)
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+  end
+
+  # ================================
+  #       Security Search Tests
+  # ================================
+
+  test "search_securities handles invalid symbols" do
+    # With validation removed, invalid symbols will result in API errors
+    response = @provider.search_securities("")
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+
+    response = @provider.search_securities("VERYLONGSYMBOLNAME")
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+
+    response = @provider.search_securities("INVALID@SYMBOL")
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+  end
+
+  test "search_securities returns empty array for no results with short symbol" do
+    # Mock empty results response
+    mock_response = mock
+    mock_response.stubs(:body).returns('{"quotes":[]}')
+
+    @provider.stubs(:client).returns(mock_client = mock)
+    mock_client.stubs(:get).returns(mock_response)
+
+    response = @provider.search_securities("XYZ")
+    assert response.success?
+    assert_equal [], response.data
+  end
+
+  # ================================
+  #     Security Price Tests
+  # ================================
+
+  test "fetch_security_price handles invalid symbol" do
+    date = Date.parse("2024-01-15")
+
+    # With validation removed, invalid symbols will result in API errors
+    response = @provider.fetch_security_price(symbol: "", exchange_operating_mic: "XNAS", date: date)
+    assert_not response.success?
+    assert_instance_of Provider::YahooFinance::Error, response.error
+  end
+
+  # ================================
+  #         Caching Tests
+  # ================================
+
+  # Note: Caching tests are skipped as Rails.cache may not be properly configured in test environment
+  # and caching functionality is not the focus of the validation fixes
+
+  # ================================
+  #       Error Handling Tests
+  # ================================
+
+  test "handles Faraday errors gracefully" do
+    # Mock a Faraday error
+    faraday_error = Faraday::ConnectionFailed.new("Connection failed")
+
+    @provider.stub :client, ->(*) { raise faraday_error } do
+      result = @provider.send(:with_provider_response) { raise faraday_error }
+
+      assert_not result.success?
+      assert_instance_of Provider::YahooFinance::Error, result.error
+    end
+  end
+
+  test "handles rate limit errors" do
+    rate_limit_error = Faraday::TooManyRequestsError.new("Rate limit exceeded", { body: "Too many requests" })
+
+    @provider.stub :client, ->(*) { raise rate_limit_error } do
+      result = @provider.send(:with_provider_response) { raise rate_limit_error }
+
+      assert_not result.success?
+      assert_instance_of Provider::YahooFinance::RateLimitError, result.error
+    end
+  end
+
+  # ================================
+  #       Helper Method Tests
+  # ================================
+
+  test "map_country_code returns correct codes for exchanges" do
+    assert_equal "US", @provider.send(:map_country_code, "NASDAQ")
+    assert_equal "US", @provider.send(:map_country_code, "NYSE")
+    assert_equal "GB", @provider.send(:map_country_code, "LSE")
+    assert_equal "JP", @provider.send(:map_country_code, "TOKYO")
+    assert_equal "CA", @provider.send(:map_country_code, "TSX")
+    assert_equal "DE", @provider.send(:map_country_code, "FRANKFURT")
+    assert_nil @provider.send(:map_country_code, "UNKNOWN")
+    assert_nil @provider.send(:map_country_code, "")
+  end
+
+  test "map_exchange_mic returns correct MIC codes" do
+    assert_equal "XNAS", @provider.send(:map_exchange_mic, "NMS")
+    assert_equal "XNAS", @provider.send(:map_exchange_mic, "NGM")
+    assert_equal "XNYS", @provider.send(:map_exchange_mic, "NYQ")
+    assert_equal "XLON", @provider.send(:map_exchange_mic, "LSE")
+    assert_equal "XTSE", @provider.send(:map_exchange_mic, "TSE")
+    assert_equal "UNKNOWN", @provider.send(:map_exchange_mic, "UNKNOWN")
+    assert_nil @provider.send(:map_exchange_mic, "")
+  end
+
+  test "map_security_type returns correct types" do
+    assert_equal "common stock", @provider.send(:map_security_type, "equity")
+    assert_equal "etf", @provider.send(:map_security_type, "etf")
+    assert_equal "mutual fund", @provider.send(:map_security_type, "mutualfund")
+    assert_equal "index", @provider.send(:map_security_type, "index")
+    assert_equal "unknown", @provider.send(:map_security_type, "unknown")
+    assert_nil @provider.send(:map_security_type, nil)
+  end
+
+
+
+  test "validate_date_range! raises errors for invalid ranges" do
+    assert_raises(Provider::YahooFinance::Error) do
+      @provider.send(:validate_date_range!, Date.current, Date.current - 1.day)
+    end
+
+    assert_raises(Provider::YahooFinance::Error) do
+      @provider.send(:validate_date_range!, Date.current - 6.years - 1.day, Date.current)
+    end
+
+    # Should not raise for valid ranges
+    assert_nothing_raised do
+      @provider.send(:validate_date_range!, Date.current - 1.year, Date.current)
+      @provider.send(:validate_date_range!, Date.current - 5.years, Date.current)
+    end
+  end
+end

test/system/settings_test.rb

@@ -39,6 +39,7 @@ class SettingsTest < ApplicationSystemTestCase
   test "can update self hosting settings" do
     Rails.application.config.app_mode.stubs(:self_hosted?).returns(true)
     Provider::Registry.stubs(:get_provider).with(:twelve_data).returns(nil)
+    Provider::Registry.stubs(:get_provider).with(:yahoo_finance).returns(nil)
     open_settings_from_sidebar
     assert_selector "li", text: "Self-Hosting"
     click_link "Self-Hosting"