# DBD::Gofer::Transport::stream - phpMan

## NAME
    [DBD::Gofer::Transport::stream] - [DBD::Gofer] transport for stdio streaming

## SYNOPSIS
      DBI->connect('dbi:Gofer:transport=stream;url=ssh:<username@host.example.com>;dsn=dbi:...',...)

    or, enable by setting the DBI_AUTOPROXY environment variable:

      export DBI_AUTOPROXY='dbi:Gofer:transport=stream;url=ssh:<username@host.example.com>'

## DESCRIPTION
    Without the "url=" parameter it launches a subprocess as

      perl -[MDBI::Gofer::Transport::stream] -e run_stdio_hex

    and feeds requests into it and reads responses from it. But that's not
    very useful.

    With a "url=ssh:<username@host.example.com>" parameter it uses ssh to
    launch the subprocess on a remote system. That's much more useful!

    It gives you secure remote access to DBI databases on any system you can
    login to. Using ssh also gives you optional compression and many other
    features (see the ssh manual for how to configure that and many other
    options via ~/.ssh/config file).

    The actual command invoked is something like:

      ssh -xq ssh:<username@host.example.com> bash -c $setup $run

    where $run is the command shown above, and $command is

      . .bash_profile 2>/dev/null || . .bash_login 2>/dev/null || . .profile 2>/dev/null; exec "$@"

    which is trying (in a limited and fairly unportable way) to setup the
    environment (PATH, PERL5LIB etc) as it would be if you had logged in to
    that system.

    The ""perl"" used in the command will default to the value of $^X when
    not using ssh. On most systems that's the full path to the perl that's
    currently executing.

## PERSISTENCE
    Currently gofer stream connections persist (remain connected) after all
    database handles have been disconnected. This makes later connections in
    the same process very fast.

    Currently up to 5 different gofer stream connections (based on url) can
    persist. If more than 5 are in the cache when a new connection is made
    then the cache is cleared before adding the new connection. Simple but
    effective.

## TO DO
    Document go_perl attribute

    Automatically reconnect (within reason) if there's a transport error.

    Decide on default for persistent connection - on or off? limits? ttl?

## AUTHOR
    Tim Bunce, <<http://www.tim.bunce.name>>

## LICENCE AND COPYRIGHT
    Copyright (c) 2007, Tim Bunce, Ireland. All rights reserved.

    This module is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself. See perlartistic.

## SEE ALSO
    [DBD::Gofer::Transport::Base]

    [DBD::Gofer]