Agiilne tarkvaraarendus kui tarkvara kvaliteedi tõstmise vahend Erik Jõgi

© Swedbank 2 Lühike eelvaade Mis on agile? –The Chaos Report –Agile Manifesto –Erinevad agile metoodikad Kuidas agile metoodikad tagavad kvaliteedi? –Quality is built-in –Funktsionaalne kvaliteet –Koodi kvaliteet –Tööprotsessi kvaliteet Kokkuvõte, küsimused

Mis on agile?

© Swedbank The Standish Group Report – 1995 “The Chaos Report” 31.1% of projects will be cancelled before they ever get completed 52.7% of projects will cost 189% of their original estimates The failure to produce reliable software to handle baggage at the new Denver airport is costing the city $1.1 million per day In 1995 American companies and government agencies will spend $81 billion for cancelled software projects Only 16.2% of software projects are completed on-time and on- budget Projects completed by the largest American companies have only approximately 42% of the originally-proposed features and functions 4

© Swedbank Manifesto for Agile Software Development We are uncovering better ways of developing software by doing it and helping others do it. Through this work we have come to value: Individuals and interactions over processes and tools Working software over comprehensive documentation Customer collaboration over contract negotiation Responding to change over following a plan That is, while there is value in the items on the right, we value the items on the left more. 5

© Swedbank Principles behind the Agile Manifesto 1/4 Our highest priority is to satisfy the customer through early and continuous delivery of valuable software Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale. 6

© Swedbank Principles behind the Agile Manifesto 2/4 Business people and developers must work together daily throughout the project. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation. 7

© Swedbank Principles behind the Agile Manifesto 3/4 Working software is the primary measure of progress. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely. Continuous attention to technical excellence and good design enhances agility. 8

© Swedbank Principles behind the Agile Manifesto 4/4 Simplicity – the art of maximizing the amount of work not done – is essential. The best architectures, requirements, and designs emerge from self-organizing teams. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly. 9

© Swedbank Agile metoodikad eXtreme Programming – XP Scrum Lean Crystal DSDM Pragmatic FDD... 10

Kuidas agile metoodikad tagavad kvaliteedi? 11

© Swedbank Quality is built-in Kõigi tegevuste koosmõjul sünnib kvaliteetne tulemus Pole tarvis eraldi Quality Assurance (QA) tegevusi – kvaliteet tagatakse läbi üldise protsessi 12

© Swedbank Funktsionaalne kvaliteet Kuidas kindlustada, et tarkvara vastab kliendi reaalsetele vajadustele ning toob kliendile olulist lisaväärtust? Tihe suhtlus kliendiga Storytelling: räägitakse läbi kogu funktsionaalsus –Klient saab tagasisidet erinevate soovide keerukusest On-site customer –Vahetu suhtlus soodustab detailide selgeks rääkimist Klient osaleb test-case’ide loomises Lühikesed iteratsioonid (1-2 nädalat) ja reliisitsükkel (1-3 kuud) –Kliendil on võimalik iga iteratsiooni lõpus suunda muuta 13

© Swedbank Koodi kvaliteet Testing: early, often and automated Teste uuesti käivitades saab alati lihtsalt veenduda, kas süsteem toimib õigesti Unit tests UI tests Testid on oluline osa rakendusest Testid on nagu dokumentatsioon Testid kirjutatakse samal ajal kui kood 14

© Swedbank Koodi kvaliteet Programmeerijate tegevused, mis aitavad suurendada koodi kvaliteeti Collective code ownership: väldime ühe inimese riski Simple design: YAGNI – you ain’t gonna need it Pair programming: –kahekesi ei kao fookus ära, toimub teadmiste jagamine Continuous integration: paneme kogu tiimi muudatused kokku Refactoring: parandame koodi struktuuri (arusaadavust) ilma funktsionaalust mõjutamata 15

© Swedbank Tööprotsessi kvaliteet Retrospective: regulaarne tagasivaade ja korrigeerimine –Keep/Problem/Try Continuous learning: pidev enesetäiendamine tagab jätkuvalt kvaliteetse tulemuse Sustainable pace: väsinud inimesed ei tee head tööd 16

© Swedbank Kokkuvõte eXtreme Programming 4 values: You need to improve communication You need to seek simplicity You need to get feedback on how well you are doing You need to always proceed with courage Kõigi tegevuste koosmõjul sünnib kvaliteetne tulemus 17