Developing Codenode

The development scripts are for running codenode components straight from the repository source tree. They facilitate a more convenient development work flow as committable changes to the source can be tested with no re-build or re-installing.

Hackable Components

Condenode is separated into a few systems each providing a distinct set of functionality.

• Browser client (JavaScript program, HTML structure, CSS style)
• Frontend server
• Backend server
• Computation engine

As an Open Source project, one important design goal is to make it so non-trivial work on any given component does not require deep understanding of the entire system. This provides contributors who may be particularly good at something like, say, JavaScript, but who also may be unexperienced with Twisted or Django, a minimally hindered development environment.

Dependencies should be available in your PYTHONPATH. It is recommended that developers install all dependencies in a virtualenv when using the devel scripts to run codenode components.

Overview

• Convenience scripts for running Frontend and Backend servers
• Convenience script for creating a codenode environment dir with o database synced with the latest models o latest default settings files for frontend and backend o latest twistd server plugin files o latest django template files
• models-shell script for playing with frontend django models in the ipython command line interpreter.
• Manhole scripts for dropping into the running frontend or backend server processes.

Server scripts

frontend-devel runs the frontend server of codenode. This uses library code from codenode.service, codenode.frontend and relies on the env/twisted/plugins/frontend_plugin.py file.

backend-devel runs the backend server of codenode. This server uses codenode.backend and codenode.engine and relies on the env/twisted/pliguins/backend_plugin.py file.

Devel environment and database

make-devel-env creates a dir called env in the codenode/devel dir. env is called a codenode environment and is the development version of:

$ codenode-admin init -name env

frontend-newdb can be used to reset the frontend database created by make-devel-env without recreating all of the env environment.

Devel mode example

Open up a terminal and type:

$ cd $CODENODE_ROOT/devel
$ ./make-devel-env
$ ./frontend-devel

Open a second terminal and type:

$ cd $CODENODE_ROOT/devel
$ ./backend-devel

Now go to http://localhost:8000/admin, log in with the username and password that you entered from ./make-devel-env, and go to “Backend servers” and add a new, with “Server address” being “http://localhost:8337“.

Manhole

Manhole is a Twisted tool. Manhole allows you to telnet or ssh into part of the namespace of a running Twisted server! Running either frontend or backend version of this tool drops you into what looks like a python command line interpreter, from which you have access to the object instances setup in either codenode.service or codenode.backend.server. By invoking appropriate methods found in twisted.python.rebuild, you can dynamically rebuild modules and classes without restarting the server! More elaborate and convenient use cases can, and hopefully will, grow out of this raw capability.