Class: RailsAiBridge::HttpTransportApp

Inherits:
Object
  • Object
show all
Defined in:
lib/rails_ai_bridge/http_transport_app.rb

Overview

Builds the Rack endpoint used by both standalone HTTP mode and the middleware auto-mount path so request handling stays in one place.

Class Method Summary collapse

Class Method Details

.build(transport:, path:) ⇒ Proc

Returns rack-compatible app.

Parameters:

  • transport (MCP::Server::Transports::StreamableHTTPTransport) —

    transport to delegate to

  • path (String) —

    configured MCP endpoint path

Returns:

  • (Proc) —

    rack-compatible app



11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
 
# File 'lib/rails_ai_bridge/http_transport_app.rb', line 11

def build(transport:, path:)
  mcp_cfg    = RailsAiBridge.configuration.mcp
  max_reqs   = mcp_cfg.effective_http_rate_limit_max_requests
  window_sec = mcp_cfg.effective_http_rate_limit_window_seconds
  limiter    = if max_reqs.positive?
                 Mcp::HttpRateLimiter.new(max_requests: max_reqs,
                                          window_seconds: window_sec)
               end

  lambda do |env|
    return [404, { 'Content-Type' => 'application/json' }, ['{"error":"Not found"}']] unless [path, "#{path}/"].include?(env['PATH_INFO'])

    request = Rack::Request.new(env)

    if mcp_cfg.require_http_auth && !Mcp::Authenticator.any_configured?
      Mcp::HttpStructuredLog.emit(request: request, event: :unauthorized, http_status: 401)
      return Mcp::Authenticator.unauthorized_rack_response
    end

    auth_result = Mcp::Authenticator.call(request)
    unless auth_result.success?
      Mcp::HttpStructuredLog.emit(request: request, event: :unauthorized, http_status: 401)
      return Mcp::Authenticator.unauthorized_rack_response
    end

    authorize = RailsAiBridge.configuration.mcp.authorize
    if authorize
      authorized = begin
        authorize.call(auth_result.context, request)
      rescue StandardError => error
        Rails.logger.error("rails_ai_bridge: authorize lambda raised #{error.class}: #{error.message}") if defined?(Rails)
        false
      end
      unless authorized
        Mcp::HttpStructuredLog.emit(request: request, event: :forbidden, http_status: 403)
        return [403, { 'Content-Type' => 'application/json' }, ['{"error":"Forbidden"}']]
      end
    end

    if limiter && !limiter.allow?(request.ip)
      Mcp::HttpStructuredLog.emit(request: request, event: :rate_limited, http_status: 429)
      return [429, { 'Content-Type' => 'application/json', 'Retry-After' => window_sec.to_s },
              ['{"error":"Too many requests"}']]
    end

    response = transport.handle_request(request)
    Mcp::HttpStructuredLog.emit(request: request, event: :handled, http_status: response.first)
    response
  end
end