Configuring Pyro

Pyro can be configured using several configuration items. The current configuration is accessible from the Pyro5.config object, it contains all config items as attributes. You can read them and update them to change Pyro’s configuration. (usually you need to do this at the start of your program). For instance, to enable message compression and change the server type, you add something like this to the start of your code:

Pyro5.config.COMPRESSION = True
Pyro5.config.SERVERTYPE = "multiplex"

You can also set them outside of your program, using environment variables from the shell. To avoid conflicts, the environment variables have a ``PYRO_`` prefix. This means that if you want to change the same two settings as above, but by using environment variables, you would do something like:

$ export PYRO_COMPRESSION=true
$ export PYRO_SERVERTYPE=multiplex

(or on windows:)
C:\> set PYRO_SERVERTYPE=multiplex

This environment defined configuration is simply used as initial values for Pyro’s configuration object. Your code can still overwrite them by setting the items to other values, or by resetting the config as a whole.

Resetting the config to default values


Resets the configuration items to their builtin default values. If use_environment is True, it will overwrite builtin config items with any values set by environment variables. If you don’t trust your environment, it may be a good idea to reset the config items to just the builtin defaults (ignoring any environment variables) by calling this method with use_environment set to False. Do this before using any other part of the Pyro library.

Inspecting current config

To inspect the current configuration you have several options:

  1. Access individual config items: print(Pyro5.config.COMPRESSION)

  2. Dump the config in a console window: python -m Pyro5.configure (or simply pyro5-check-config) This will print something like:

    Pyro version: 5.10
    Loaded from: /home/irmen/Projects/pyro5/Pyro5
    Python version: CPython 3.8.2 (Linux, posix)
    Protocol version: 502
    Currently active global configuration settings:
    BROADCAST_ADDRS = ['<broadcast>', '']
  3. Access the config as a dictionary: Pyro5.config.as_dict()

  4. Access the config string dump (used in #2): Pyro5.config.dump()

Overview of Config Items

config item type default meaning
COMMTIMEOUT float 0.0 Network communication timeout in seconds. 0.0=no timeout (infinite wait)
COMPRESSION bool False Enable to make Pyro compress the data that travels over the network
DETAILED_TRACEBACK bool False Enable to get detailed exception tracebacks (including the value of local variables per stack frame)
HOST str localhost Hostname where Pyro daemons will bind on
MAX_MESSAGE_SIZE int 1073741824 (1 Gb) Maximum size in bytes of the messages sent or received on the wire. If a message exceeds this size, a ProtocolError is raised.
NS_HOST str equal to HOST Hostname for the name server. Used for locating in clients only (use the normal HOST config item in the name server itself)
NS_PORT int 9090 TCP port of the name server. Used by the server and for locating in clients.
NS_BCPORT int 9091 UDP port of the broadcast responder from the name server. Used by the server and for locating in clients.
NS_BCHOST str None Hostname for the broadcast responder of the name server. Used by the server only.
NS_AUTOCLEAN float 0.0 Specify a recurring period in seconds where the Name server checks its registrations and removes the ones that are not available anymore. (0=disabled, otherwise should be >=3)
NS_LOOKUP_DELAY float 0.0 The max. number of seconds a name lookup will wait until the name becomes available in the nameserver (client-side retry)
NATHOST str None External hostname in case of NAT (used by the server)
NATPORT int 0 External port in case of NAT (used by the server) 0=replicate internal port number as NAT port
BROADCAST_ADDRS str <broadcast>, List of comma separated addresses that Pyro should send broadcasts to (for NS locating in clients)
ONEWAY_THREADED bool True Enable to make oneway calls be processed in their own separate thread
POLLTIMEOUT float 2.0 For the multiplexing server only: the timeout of the select or poll calls
SERVERTYPE str thread Select the Pyro server type. thread=thread pool based, multiplex=select/poll/kqueue based
SOCK_REUSE bool True Should SO_REUSEADDR be used on sockets that Pyro creates.
SOCK_NODELAY bool False Use tcp_nodelay on sockets
PREFER_IP_VERSION int 0 The IP address type that is preferred (4=ipv4, 6=ipv6, 0=let OS decide).
SERPENT_BYTES_REPR bool False If True, use Python’s repr format to serialize bytes types, rather than the base-64 encoding format.
THREADPOOL_SIZE int 80 For the thread pool server: maximum number of threads running
THREADPOOL_SIZE_MIN int 4 For the thread pool server: minimum number of threads running
SERIALIZER str serpent The wire protocol serializer to use for clients/proxies (one of: serpent, json, marshal, msgpack)
LOGWIRE bool False If wire-level message data should be written to the logfile (you may want to disable COMPRESSION)
MAX_RETRIES int 0 Automatically retry network operations for some exceptions (timeout / connection closed), be careful to use when remote functions have a side effect (e.g.: calling twice results in error)
ITER_STREAMING bool True Should iterator item streaming support be enabled in the server (default=True)
ITER_STREAM_LIFETIME float 0.0 Maximum lifetime in seconds for item streams (default=0, no limit - iterator only stops when exhausted or client disconnects)
ITER_STREAM_LINGER float 30.0 Linger time in seconds to keep an item stream alive after proxy disconnects (allows to reconnect to stream)
SSL bool False Should SSL/TSL communication security be used? Enabling it also requires some other SSL config items to be set.
SSL_SERVERCERT str empty str Location of the server’s certificate file
SSL_SERVERKEY str empty str Location of the server’s private key file
SSL_SERVERKEYPASSWD str empty str Password for the server’s private key
SSL_REQUIRECLIENTCERT bool False Should the server require clients to connect with their own certificate (2-way-ssl)
SSL_CLIENTCERT str empty str Location of the client’s certificate file
SSL_CLIENTKEY str empty str Location of the client’s private key file
SSL_CLIENTKEYPASSWD str empty str Password for the client’s private key
SSL_CACERTS str empty str Location of a ‘CA’ signing certificate (or a directory containing these in PEM format, “following an OpenSSL specific layout”.)

There are two special config items that control Pyro’s logging, and that are only available as environment variable settings. This is because they are used at the moment the Pyro5 package is being imported (which means that modifying them as regular config items after importing Pyro5 is too late and won’t work).

It is up to you to set the environment variable you want to the desired value. You can do this from your OS or shell, or perhaps by modifying os.environ in your Python code before importing Pyro5.

environment variable type default meaning
PYRO_LOGLEVEL string not set The log level to use for Pyro’s logger (DEBUG, WARN, …) See Python’s standard logging module for the allowed values. If it is not set, no logging is being configured.
PYRO_LOGFILE string pyro.log The name of the log file. Use {stderr} to make the log go to the standard error output.