Molecule

Molecule is a component oriented framework for Pharo. His Component architecture approach provide an adapted structuration to graphic user interface (GUI) or another software application wich need Component features.

Molecule provide a way to describe a software application as a components group. Components communicate by use of services, parameters and events propagation. It is a Pharo implementation of the Lightweight Corba Component Model (Lightweight CCM). Molecule support completely transparent class augmentation into component (not necessary to add code manually), based on Traits.

Getting Started

Installing Molecule

Pharo 8 and Pharo 9 :

Metacello new
   baseline: 'Molecule';
   repository: 'github://OpenSmock/Molecule';
   load.

Deprecated version of Molecule (1.1.x) for Pharo 6 and 7 is also available here.

Prerequisites

Molecule Core has no dependencies. Package 'Molecule-Benchmarks' requires SMark (https://github.com/smarr/SMark), this package contains benchmarks for working on performances.

UI Tools overview

UI Tools are comming in next versions of Molecule. They are currently in development in Incubators packages but are ready to use.

Installing Incubators packages for Pharo 9 (not tested on Pharo 8) :

Metacello new
   baseline: 'MoleculeIncubator';
   repository: 'github://OpenSmock/Molecule';
   load.

Using Components

Start and stop method

Components can be used with the start & stop method.

To start a component :

component := MyComponentClass start.

To stop a component :

MyComponentClass stop.

Component can be identified with a name. To start a component with a specific name :

componentA := MyComponentClass start: #componentA.

To stop a component identified by a name.

MyComponentClass stop: #componentA.

Component Life-cycle method

Components can be used with the life-cycle method, the two methods (start & stop, life-cycle) can be combined.

Start a component is equivalent to :

MyComponentClass deploy.
component := MyComponentClass instanciate.
MyComponentClass activate.

With a name :

MyComponentClass deploy.
componentA := MyComponentClass instanciate: #compA.
MyComponentClass activate: #compA.

Stop a component is equivalent to :

MyComponentClass passivate.
MyComponentClass remove.
MyComponentClass undeploy.

With a name :

MyComponentClass passivate: #compA.
MyComponentClass remove: #compA.
MyComponentClass undeploy.

Some examples

Examples are available in the package 'Molecule-Examples'. Before running examples open the Transcript, some results are showed on the Transcript window.

Clock System example

MolMyClockSystem startAlarmExample.

This system uses 4 components: a server time send global hour to a clock. The clock send local hour to alarms and to final user (which could be an UI). The final user can change the parameters of the system as alarm time or set manual time for the clock. The alarm is subscribed to clock time, and sounds when it is time.

This system provides a global example of the use of components.

GPS example

MolGPSExampleLauncher start.

More details about examples in the comment of MolGPSExampleLauncher.

First we program a component application that connects to a Global Positioning System (GPS) hardware and displays the GPS data on a view map (just fictitious). The GPS data and view map are implemented as Molecule components. In a second way, we reuse an existing non-component class in our Molecule application (MolGPSHardware). To do so, we augment this class with component behavior.

Test coverage

Molecule includes more than 175 unit tests, we have also written tests that simulate the work of a developer when creating and modifying components. Test coverage is detailed in the release notes.

Credits

Pierre Laborde - Initial work - labordep
Eric Le Pors - Initial work - ELePors
Nolwenn Fournier - Initial work - nolwennfournier
Alain Plantec - Initial work - plantec
Lisa Doyen - UI Components Tools - lisadoyen

License

This project is licensed under the MIT License - see the LICENSE file for details.

lisadoyen/Molecule-1