Flow-Based Programming for Node.js

http://bergie.iki.fi henri.bergius@iki.fi

@bergie

Call-Return

Continuation-Passing Style

JavaScript, the Ugly Parts

Promises

Hooks

How to make your code manageable?

Clean separation of concerns

Visualized connections between components

Flow-based programming

“Flow-based programming (FBP) is a programming paradigm that defines applications as networks of 'black box' processes, which exchange data across predefined connections by message passing, where the connections are specified externally to the processes. These black box processes can be reconnected endlessly to form different applications without having to be changed internally. FBP is thus naturally component-oriented.”

- Wikipedia

Flow-based programming

“Flow-Based Programming was invented by John Paul Morrison [from IBM] in the early 1970s, and an early implementation of this technology has been in continuous production use at a major Canadian bank since that time.”

- Wikipedia

Software archeology?

“This is the Unix philosophy: Write programs that do one thing and do it well. Write programs to work together. Write programs to handle text streams, because that is a universal interface.”

- Doug McIlroy

“I thought of objects being like biological cells and/or individual computers on a network, only able to communicate with messages (so messaging came at the very beginning -- it took a while to see how to do messaging in a programming language efficiently enough to be useful).”

- Alan Kay

send options 'a, u & x' to command 'ps',send option 'firefox' to command 'grep'direct standard output of 'ps' to 'grep'

NoFlo components

Using NoFlo in your Node.js app

Using NoFlo in your Node.js app

DSL for specifying flows

DSL for specifying flows

send string 'package.json' to source port of Readsend output of Read to Split (by lines)

send output of Split to Countsend output of Count to Display

NoFlo shell

NoFlo in integration

CouchDB+

CouchAppProject

Controller

Externalpartners

Externalsystems

email

NoFlo

github.com/iks/proggis

NoFlo in integration

github.com/iks/proggis

NoFlo in real world

What happens next?

● Web-based drawing ● Web-based

monitoring & debug

● Hook.io support● Component loading

from NPM

Flow-Based Programming, the book

amzn.com/1451542321

Flow-Based Programming for Node.js

github.com/bergie/noflo

github.com/bergie/noflo

Screenshot: github.com, couple of weeks ago