OpenCog CogServer

opencog	singnet

The OpenCog Cogserver is a network scheme/python command-line and job server for the OpenCog framework.

Overview

The CogServer provides a network command-line console server and a job scheduler. The network console server provides a fast, efficient telnet interface, giving access to Scheme (guile) and Python command-lines. Both can be used by multiple users at the same time, all obtaining access to the same AtomSpace. This is very useful for running ad-hoc commands, monitoring status, poking around and performing general maintenance on long-running OpenCog or AtomSpace processes (e.g. robot control, large batch-job processing or long-running data-mining servers.)

Having a network command line is notable: by default, Python does not allow multiple users to access it at the same time. As to scheme/guile, there is an ice-9 REPL server, but the CogServer is an order of magnitude faster, lower latency/higher throughput, and infinitely more stable; its free of lockups, hangs and crashes.

The Cogserver provides not only a convenient interface for ad-hoc data hacking, but also provides a very good (and easy, and strong) way of doing bulk data transfers. In particular, the transfer of multiple megabytes of Atoms and (Truth)Values as UTF-8 (i.e. human-readable) text is easy and efficient. In particular, it does not require fiddling with complex binary formats or protocols or the use of protocol libraries or API's. (We're looking at you, HTTP, REST, ZeroMQ, ProtoBuff and friends. You are all very sophisticated, yes, but are hard to use. And sometimes painfully slow.)

The job scheduler (aka 'MindAgents' or just 'Agents') is an experimental prototype for controlling multiple threads and assigning thread processing priorities, in an AtomSpace-aware fashion. It is in need of the caring love and attention from an interested developer.

For more info, please consult the CogServer wiki page.

Using

There are three ways to start the cogserver: from a bash shell prompt (as a stand-alone process), from the guile command line, or from the python command line.

From bash, just start the process: $ build/opencog/cogserver/server/cogserver
From guile: (use-modules (opencog cogserver)) (start-cogserver)
From python: import opencog.cogserver and then ??? start_cogserver() ??? (where's the documentation for this?)

Once started, one can obtain a shell by saying rlwrap telnet localhost 17001, and then py or scm to obtain a python or scheme shell. This can be done as many times as desired; all shells share the same AtomSpace, and the system is fully multi-threaded/thread-safe.

The rlwrap utility simply adds arrow-key support, so that up-arrow provides a command history, and left-right arrow allows in-place editing. Note that telnet does not provide any password protection! It is fully networked, so you can telnet from other hosts. The default port number 17001 can be changed; see the documentation.

Building and Running

The CogServer is built exactly the same way that all other OpenCog components are built:

clone https://github.com/opencog/cogserver
cd cogserver
mkdir build
cd build
cmake ..
make -j

For additional information on dependencies and general hand-holding with the build, see the building Opencog wiki.

Prerequisites

To build and run the CogServer, you need to install the AtomSpace first.

AtomSpace

OpenCog AtomSpace database http://github.com/opencog/atomspace It uses exactly the same build procedure as this package. Be sure to sudo make install at the end.

Unit tests

To build and run the unit tests, just say

    make test

from the ./build directory.

leungmanhin / cogserver