Provided by: libnetsds-perl_1.301-3_all 
NAME
NetSDS::App::JSRPC - JSON-RPC server framework
SYNOPSIS
#!/usr/bin/env perl
# JSON-RPC server
use 5.8.0;
use warnings;
use strict;
JServer->run();
1;
# Server application logic
package JServer;
use base 'NetSDS::App::JSRPC';
# This method is available via JSON-RPC
sub sum {
my ($self, $param) = @_;
return $$param[0] + $$param[1];
}
1;
DESCRIPTION
"NetSDS::App::JSRPC" module implements framework for common JSON-RPC based server
application. JSON-RPC is a HTTP based protocol providing remote procudure call (RPC)
functionality using JSON for requests and responses incapsulation.
This implementation is based on NetSDS::App::FCGI module and expected to be executed as
FastCGI or CGI application.
Diagram of class inheritance:
[NetSDS::App::JSRPC] - JSON-RPC server
|
[NetSDS::App::FCGI] - CGI/FCGI application
|
[NetSDS::App] - common application
|
[NetSDS::Class::Abstract] - abstract class
Both request and response are JSON-encoded strings represented in HTTP protocol as data of
'application/json' MIME type.
APPLICATION DEVELOPMENT
To develop new JSON-RPC server application you need to create application class inherited
from "NetSDS::App::JSRPC":
It's just empty application:
#!/usr/bin/env perl
JSApp->run(
conf_file => '/etc/NetSDS/jsonapp.conf'
);
package JSApp;
use base 'NetSDS::App::JSRPC';
1;
Alsoe you may want to add some specific code for application startup:
sub start {
my ($self) = @_;
connect_to_dbms();
query_for_external_startup_config();
do_other_initialization();
}
And of course you need to add methods providing necessary functions:
sub send_sms {
my ($self, $params) = @_;
return $self->{kannel}->send(
from => $params{'from'},
to => $params{'to'},
text => $params{'text'},
);
}
sub kill_smsc {
my ($self, $params) = @_;
# 1M of MT SM should be enough to kill SMSC!
# Otherwise we call it unbreakable :-)
for (my $i=1; $<100000000; $i++) {
$self->{kannel}->send(
%mt_sm_parameters,
);
}
if (smsc_still_alive()) {
return $self->error("Can't kill SMSC! Need more power!");
}
}
ADVANCED FUNCTIONALITY
"NetSDS::App::JSRPC" module provides two methods that may be used to implement more
complex logic than average RPC to one class.
can_method() - method availability checking
By default it is just wrapper around "UNIVERSAL::can" function. However it may be
rewritten to check for methods in other classes or even construct necessary methods on
the fly.
process_call() - method dispatching
By default it just call local class method with the same name as in JSON-RPC call. Of
course it can be overwritten and process query in some other way.
This code describes logic of call processing:
# It's not real code
if (can_method($json_method)) {
process_call($json_method, $json_params);
}
For more details read documentation below.
CLASS API
new(%params) - class constructor
It's internally used constructor that shouldn't be used from application directly.
process() - main JSON-RPC iteration
This is internal method that implements JSON-RPC call processing.
can_method($method_name) - check method availability
This method allows to check if some method is available for execution. By default it
use "UNIVERSAL::can" but may be rewritten to implement more complex calls dispatcher.
Paramters: method name (string)
Return true if method execution allowed, false otherwise.
Example:
# Rewrite can_method() to search in other class
sub can_method {
my ($self, $method) = @_;
return Other::Class->can($method);
}
process_call($method, $params) - execute method call
Paramters: method name, parameters.
Returns parameters from executed method as is.
Example:
# Rewrite process_call() to use other class
sub process_call {
my ( $self, $method, $params ) = @_;
return Other::Class->$method($params);
}
_request_parse($post_data) - parse HTTP POST
Paramters: HTTP POST data as string
Returns: request method, parameters, id
_make_result(%params) - prepare positive response
This is internal method for encoding JSON-RPC response string.
Paramters:
id - the same as request Id (see specification)
result - method result
Returns JSON encoded response message.
_make_error(%params) - prepare error response
Internal method implementing JSON-RPC error response.
Paramters:
id - the same as request Id (see specification)
code - error code (default is -32603, internal error)
message - error message
Returns JSON encoded error message
EXAMPLES
See "samples/app_jsrpc.fcgi" appliction.
SEE ALSO
JSON
JSON::RPC2
<http://json-rpc.org/wiki/specification> - JSON-RPC 1.0
<http://groups.google.com/group/json-rpc/web/json-rpc-1-2-proposal> - JSON-RPC 2.0
TODO
1. Move error codes to constants to provide more clear code.
2. Implement objects/classes support.
AUTHOR
Michael Bochkaryov <misha@rattler.kiev.ua>
LICENSE
Copyright (C) 2008-2009 Net Style Ltd.
This program is free software; you can redistribute it and/or modify it under the terms of
the GNU General Public License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program;
if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
MA 02111-1307 USA