module AeNetworkConnectionException

# File lib/ae_network_connection_exception.rb, line 32
def exception_signatures
  [
    SocketError.new('getaddrinfo: Name or service not known'),
    Errno::ECONNREFUSED.new('Connection refused - connect(2) for "example.com" port 443'),
    Errno::ETIMEDOUT.new('Connection timed out - connect(2) for "example.com" port 443'),
    Net::OpenTimeout.new('message'),
    Errno::ECONNRESET.new('Connection reset by peer - SSL_connect'),
    Errno::EHOSTUNREACH.new('No route to host - connect(2) for "example.com" port 443'),
    Errno::ENETUNREACH.new('Network is unreachable - connect(2) for "example.com" port 443')
  ]
end

# File lib/ae_network_connection_exception.rb, line 11
def try
  yield
rescue SocketError, Net::OpenTimeout, *other_exceptions
  # SocketError happens when we fail to connect to a socket.
  # Common problems here are DNS resolution (i.e. getaddrinfo).
  # Net::OpenTimeout happens when we are unable to establish an HTTP connection before the open_timeout.
  raise ConnectionNotEstablished
rescue Errno::ETIMEDOUT, Errno::ECONNREFUSED, Errno::EHOSTUNREACH, Errno::ENETUNREACH => e
  # Errno::ECONNREFUSED happens when we can not connect to the port.
  # Errno::ETIMEDOUT happens when we timeout durring the tcp handshake.
  # Errno::ETIMEDOUT can also happen after we have established a connection and are waiting for a response.
  # Because of this, we also check that the sys call that was made is connect(2).
  # Errno::* Exceptions have the following error message format:
  #   "#{Message string} - #{syscall} for "#{host}" port #{port}"
  raise_if_exception_message_matches(e, /connect\(2\)/)
rescue Errno::ECONNRESET => e
  # Errno::ECONNRESET happens when the connection is reset. This can happen during SSL negotiation.
  raise_if_exception_message_matches(e, /SSL_connect/)
end

# File lib/ae_network_connection_exception.rb, line 46
def other_exceptions
  res = []
  res << RestClient::Exceptions::OpenTimeout if defined?(RestClient::Exceptions::OpenTimeout)
  res << HTTP::ConnectTimeoutError if defined?(HTTP::ConnectTimeoutError)

  res
end

# File lib/ae_network_connection_exception.rb, line 54
def raise_if_exception_message_matches(exception, pattern)
  raise ConnectionNotEstablished if exception.message =~ pattern

  raise exception
end