Erlang Component Framework

This project aims to be a faithful implementation of the component model presented in C. Cachin, R. Guerraoui, and L. Rodrigues, Introduction to Reliable and Secure Distributed Programming. Springer-Verlag, Berlin 2nd Edition, 2011. That said, this software is unfinished, and for more developed stacks we suggest Appia or Kompics.

Modules and applications are implemented as callback functions on an event model, where each component waits for messages published by components below it in the stack, its own state, and the messages it publishes for components or applications higher in the stack.

This approach eases building and reasoning about algorithms such as consensus or total order broadcast by making use of simpler abstractions such as perfect links and point-to-point orderings, and making explicit the failure model assumed and detectors used.

Usage notes

The following are residual notes not yet cleaned up, and may not be useful documentation. The files projects/dancing-robot-project/lab3-implementing-basic-abstractions.pdf and projects/dancing-robot-project/assignment.pdf may be more useful.

bundling erlang code as applications

OTP defines the usual directory structure, best to just use this

how/why basis: http://learnyousomeerlang.com/designing-a-concurrent-application

OTP template generator / build tool: https://github.com/basho/rebar/wiki/Getting-started

compiling debug info enabled code (for the debugger) with rebar

set in rebar.config:

{erl_opts, [debug_info]}.

running rebar compiled code in the erl shell

cd(ebin).

so that the compiled modules are accessible. You don't need to compile with "c" inside erl, but will want to restart erl after recompiling to make sure you have the latest beam files loaded (Erlang provides methods for updating code in a running system, but it's out-of-scope here).

run stack and test sl:

open 2 terminals;

terminal 1:

cd to this directory
./rebar compile # should be no errors
erl -sname foo
cd(ebin).
stack:start_link().
stack:add_component(sl).
node().

terminal 2:

cd to this directory
erl -sname bar
cd(ebin).
stack:start_link().
stack:add_component(sl).
stack:trigger({sl, send, PUT_TERMINAL1_NODE_RESULT_HERE, knock_knock}).

run stack and test pl:

open 2 terminals;

terminal 1:

cd to this directory
./rebar compile # should be no errors
erl -sname foo
cd(ebin).
stack:start_link().
stack:add_component(pl).
node().

terminal 2:

cd to this directory
erl -sname bar
cd(ebin).
stack:start_link().
stack:add_component(pl).
stack:trigger({pl, send, 'bar@ntr-macbook-pro', knock_knock}).

run robots

cp projects/dancing-robot-project/dancing_robots.erl src/
./rebar compile # should be no errors

See robots assignment.pdf for launch instructions