experiencias industriales con programación declarativa
DESCRIPTION
Building software imposes a set of general challenges, which are complemented by those specific to the business context. The use of declarative programming as key implementation technology provides several advantages in both areas, a fact that has not gone unnoticed by companies of all sizes and domains. In particular, the functional programming language Erlang is getting big momentum in the last years thanks to its built-in capabilities for high availability, robustness, maintainability. This presentation shows some practical examples and discusses the role that the implementation technology (Erlang) played in their successful outcome.TRANSCRIPT
Experiencias Industrialescon Programación Declarativa
Laura M. [email protected]
www.madsgroup.org/staff/laura
MADS
● Models and Applications of Distributed Systems
http://www.madsgroup.org● Core language: Erlang● Well-known results:
– VoDKA: Video on Demand system
– ARMISTICE: Advanced Risk Management Information System
– Syntheractive
– ADVERTISE
2 spin-offs
MADS
● Models and Applications of Distributed Systems
http://www.madsgroup.org● Core language: Erlang● Well-known results:
– VoDKA: Video on Demand system
– ARMISTICE: Advanced Risk Management Information System
– Syntheractive
– ADVERTISEcollaborationwith industry
2 spin-offs
MADS
● Models and Applications of Distributed Systems
http://www.madsgroup.org● Core language: Erlang● Well-known results:
– VoDKA: Video on Demand system
– ARMISTICE: Advanced Risk Management Information System
– Syntheractive
– ADVERTISE2 spin-offs
● Functional programming language● Developed by Ericsson in the mid-eighties, open
source since 1998● Dynamically typed, eager evaluation● Key features:
– Concurrency: lightweight processes, own memory space, asynchronous message passing
– Distribution: several VMs on several nodes
– High avalilability: links between processes, built-in fault-tolerance mechanisms
Erlang
VoDKA
VoDKATV
ARMISTICE
The key: Erlang
● Erlang features common to all these projects– Supervision, monitoring
● Lightweight processes● Behaviours (lots of boilerplate for free!)
– Seamless distribution
– Nonstop code upgrade
The key: Erlang
● Erlang features common to all these projects– Supervision, monitoring
● Lightweight processes● Behaviours (lots of boilerplate for free!)
– Seamless distribution
– Nonstop code upgrade
– Pattern-matching
– List comprehensions
– Functions as first-class citizens
The key: Erlang
● Erlang features common to all these projects– Supervision, monitoring
● Lightweight processes● Behaviours (lots of boilerplate for free!)
– Seamless distribution
– Nonstop code upgrade
– Pattern-matching
– List comprehensions
– Functions as first-class citizens
● Current research: software testing– Specifically: model-based and property-based
testing
● 2 European research projects:– ProTest (http://protestproject.eu): 2007-2011
– PROWESS (http://prowessproject.eu): 2012-2015
MADS (today)
● Uses declarative statements to specify properties that the software needs to satisfy according to its specification
● Using this approach:– Test cases can be automatically derived from
those properties
– Test cases can be automatically run and diagnosed
● PBT in Erlang:– QuickCheck / PropEr
ProTest: Property-based testing
● Reduce time spent on testing, whilst increasing software quality
– In order to quickly launch new, or enhancements of existing, web services and internet applications
● Provide the European software industry with efficient and effective testing tools and techniques for web services
– Erlang/QuickCheck as core tools/technologies
PROWESS: PBT for web services