Class: MailCatcher::Integrations::MCPServer

Inherits:
Object
  • Object
show all
Defined in:
lib/mail_catcher/integrations/mcp_server.rb

Overview

MCP Server Implements the Model Context Protocol (MCP) over stdio Allows Claude and other MCP clients to interact with MailCatcher tools

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(options = {}) ⇒ MCPServer

Returns a new instance of MCPServer.



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# File 'lib/mail_catcher/integrations/mcp_server.rb', line 14

def initialize(options = {})
  @options = options
  @running = false
  @request_id_counter = 0
end

Instance Attribute Details

#running ⇒ Object

Returns the value of attribute running.



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# File 'lib/mail_catcher/integrations/mcp_server.rb', line 12

def running
  @running
end

Class Method Details

.start(options = {}) ⇒ Object 



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# File 'lib/mail_catcher/integrations/mcp_server.rb', line 20

def self.start(options = {})
  server = new(options)
  server.run
  server
end

Instance Method Details

#run ⇒ Object

Main server loop - handles JSON-RPC messages from stdin



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# File 'lib/mail_catcher/integrations/mcp_server.rb', line 27

def run
  @running = true
  $stderr.puts "[MCP Server] Starting MailCatcher MCP Server"

  # Output MCP initialization
  send_response(
    jsonrpc: "2.0",
    id: 0,
    result: {
      protocolVersion: "2024-11-05",
      capabilities: {
        tools: {},
        resources: {},
        logging: {}
      },
      serverInfo: {
        name: "mailcatcher-ng",
        version: MailCatcher::VERSION
      }
    }
  )

  # Main loop - read and process requests
  while @running && (line = $stdin.gets)
    begin
      request = JSON.parse(line)
      handle_request(request)
    rescue JSON::ParserError => e
      $stderr.puts "[MCP Server] JSON parse error: #{e.message}"
      send_error_response(nil, -32700, "Parse error")
    rescue => e
      $stderr.puts "[MCP Server] Error: #{e.message}"
      $stderr.puts e.backtrace.first(5)
    end
  end

  $stderr.puts "[MCP Server] MCP Server stopped"
  @running = false
end

#stop ⇒ Object 



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# File 'lib/mail_catcher/integrations/mcp_server.rb', line 67

def stop
  @running = false
end