DBD::Gofer::Transport:UsereContributed Perl DocuDBD::Gofer::Transport::Base(3)NAMEDBD::Gofer::Transport::Base - base class for DBD::Gofer client
my $remote_dsn = "..."
or, enable by setting the DBI_AUTOPROXY environment variable:
which will force all DBI connections to be made via that Gofer server.
This is the base class for all DBD::Gofer client transports.
Gofer transport attributes can be specified either in the attributes
parameter of the connect() method call, or in the DSN string. When used
in the DSN string, attribute names don't have the "go_" prefix.
The full DBI DSN that the Gofer server should connect to on your
When used in the DSN it must be the last element in the DSN string.
A time limit for sending a request and receiving a response. Some
drivers may implement sending and receiving as separate steps, in which
case (currently) the timeout applies to each separately.
If a request needs to be resent then the timeout is restarted for each
sending of a request and receiving of a response.
The maximum number of times an request may be retried. The default is
This subroutine reference is called, if defined, for each response
received where $response->err is true.
The subroutine is pass three parameters: the request object, the
response object, and the transport object.
If it returns an undefined value then the default retry behaviour is
used. See "RETRY ON ERROR" below.
If it returns a defined but false value then the request is not resent.
If it returns true value then the request is resent, so long as the
number of retries does not exceed "go_retry_limit".
RETRY ON ERROR
The default retry on error behaviour is:
- Retry if the error was due to DBI_GOFER_RANDOM. See L<DBI::Gofer::Execute>.
- Retry if $request->is_idempotent returns true. See L<DBI::Gofer::Request>.
A retry won't be allowed if the number of previous retries has reached
Tracing of gofer requests and reponses can be enabled by setting the
"DBD_GOFER_TRACE" environment variable. A value of 1 gives a reasonably
compact summary of each request and response. A value of 2 or more
gives a detailed, and voluminous, dump.
The trace is written using DBI->trace_msg() and so is written to the
default DBI trace output, which is usually STDERR.
This section is currently far from complete.
$retry = $transport->response_retry_preference($request, $response);
The response_retry_preference is called by DBD::Gofer when considering
if a request should be retried after an error.
Returns true (would like to retry), false (must not retry), undef (no
If a true value is returned in the form of a CODE ref then, if
DBD::Gofer does decide to retry the request, it calls the code ref
passing $retry_count, $retry_limit. Can be used for logging and/or to
implement exponential backoff behaviour. Currently the called code
must return using "return;" to allow for future extensions.
Tim Bunce, <http://www.tim.bunce.name>
LICENCE AND COPYRIGHT
Copyright (c) 2007-2008, 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.
DBD::Gofer, DBI::Gofer::Request, DBI::Gofer::Response,
and some example transports:
perl v5.10.1 2009-02-24 DBD::Gofer::Transport::Base(3)