#3rd party libraries

Есть два диаметрально противоположных подхода организации работы с библиотеками на проекте: пишем все свое и берем все чужое. Мне довелось поработать в обеих ситуациях. Хочу поделиться плюсами и минусами этих подходов, а также идеями как облегчить себе жизнь.

Все Свое

Как правило это ситуация с микроконтроллерами, где вы не можете просто взять и использовать код не доработав его напильником под свое железо, или что-то очень-очень секьюрное, где паранойя о том, что везде могут быть чьи-то “закладки” не дает покоя заказчику проекта, или многоплатформенное, и вам надо иметь суперуниверсальный код. 

Если вы пишете все свое, то вы сразу же отбрасываете опыт разработчика-автора либы: он уже сталкивался с вашими проблемами, он тестировал, он находил проблемы производительности, он чинил баги, которые ему зарепортили другие пользователи, он писал автотесты.

Разработка собственных либ как правило идет параллельно с разработкой вашего проекта. И вы попадаете в ситуацию: “пока враг рисует карты, мы меняем ландшафты”. Требуется версионирование собственных либ, чтобы ваш код был в синхронизации с кодом библиотек.

Если либ больше чем одна, вы очень скоро упретесь в то, что версии не стыкуются. Вам нужна либа А версии 1.2, но она не стыкуется с либой Б версии 2.3, а стыкуется только с либой Б версии 2.5, а ваш код не совместим с версией либы Б выше 2.4. Апгрейды версий придется чщательно планировать и изучать зависимости.

Откат к предыдущим версиям - ровно такая же боль. Если вы вдруг находите критический баг, который починить невозможно, и принимаете решение откатиться к предыдущему набору версий либ - вы получаете проблему того, что новый код уже опирается на какие-то новые фичи, которых не было в предыдущем наборе. Выход - врапперы над интерфейсом либ, и максимально изолировать влияние интерфейса либы на бизнеслогику кода в проекте.

Из-за параллельной разработки проекта и либ, все добро приходится собирать с исходников, от самого низа. Поэтому время сборки значительно возрастает по мере развития проекта.

Но, конечно же такой подход дает один неоспоримый плюс: вы можете найти и починить ЛЮБОЙ баг, ЛЮБЫМ способом.

Вы познаёте все, даже малейшие проблемы на своем личном опыте. И можете объяснить поведение программы.

Все чужое

Либа может быть хорошая, но ее лицензия не позволит вам использовать ее у себя.

Вы берете готовые библиотеки, и если у разработчика были прямые руки - все начинает работать сразу. Но даже если у разработчика были самые прямые руки, все равно есть какие-то особенности, про которые вы узнаете в лучшем случае на этапе тестирования, в худшем - после релиза, от пользователя.

Баги можно зарепортить, но не факт что автор согласится что это баг, или не выставит багу самый низкий приоритет отложив когда-то на потом. Или скажет, что это очень специфический случай, ради которого никто ничего переделывать не будет. То есть придется тулить костыли.

Иногда что-то будет крэшиться, и вы ничего не сможете с этим сделать. Поэтому вполне нормальным вариантом будет вынесение работы с такой либой в отдельный процесс, с которым ваше приложение общается по LPC/RPC.

Вы не управляете производительностью и потреблением ресурсов. Т.е. при выборе библиотеки нужно тщательно смотреть как ведет себя либа.

Иногда либа будет настолько сырая, что проще будет ее переписать самому, чем использовать в том виде в каком она есть.

Либа может идти в бинарях и требовать тягать за собой рантайм от какой-то лохматой версии компилятора.

Либа может быть собрана так, что будет конфликтовать с другими вашими библиотеками. Привет-привет ffmpeg например. И вам придется пересобирать либу через чудопроцедуры описанные разработчиком.

Отладочная инфа зачастую отсутствует, поэтому вы не знаете: или это ваш код так неправильно либу использует, или очередной баг в коде либы. Выход: если есть исходный код - лучше собирать либу самому, под свой проект.

Пересборка чужих либ под свои нужды - отдельный аттракцион, особенно если автор в новой версии резко изменил процедуру сборки, или добавил новые зависимости. Есть вариант облегчающий эти вещи - использовать менеджеры пакетов nuget, conan и т. п.

Либа может не иметь релизов: автор распиздяй - херачит все в master. И вы никогда не знаете - удачно вы схватили исходники, или автор вчера какую-то хрень залил.

Может банально не быть либы собранной под x64, а исходников нет. Или либа не была готова к кроссплатформенности и не собирается под вашу платформу без дополнительных изменений.

Есть патчи, которые автор либы не принял, а вам без них нельзя. При апгрейде либы вы должны их каждый раз накатывать, и тратить время на то чтобы понять, а где ж теперь тот код, который я патчил в прошлом году.

DLL Hell as is, здесь та же проблема что и при сборке всего своего - вам придется собирать набор библиотек, которые не конфликтуют между собой. Но тут за счет того, что библиотеки меняются редко, мучиться приходится не так часто.

Апгрейд версий тоже нужно тщательно планировать. Врапперы также спасают от резких изменений интерфейса.

Django bump exist defined as a high-level Python Framework that helps the users to occur up with faster as well as cleaner story along with magisterial realistic designing of websites. Developers today prefer up to use Django over Ruby on Rails due to certain reasons. They are described below:<\p>

Idiom <\p>

Python is a bit articulated now a shan. You will find definite guidelines along next to computer program, per se carelessly the way the codes are to be written or formatted. Save, alterum will also maintain a clean structure in the codes, irrespective with regard to whatever i do. In fact, the framework follows the wholesome long-lived principle that says, €Codes are more read than they are flowing.€ <\p>

Set of 3rd party Libraries <\p>

When self comes to 3rd out-group libraries, using Python will not masquerade as each one problem for the developer. The libraries are persuasive as well as mature enough upon cook up coding seamless as well insofar as fast parce que well as free of hiccups. <\p>

Helper Tools <\p>

It comes thicken in addition to some helper tools that will make the esprit of the developers much easier. These tools help you maintain by what mode well considering deploy the codes. If a developer takes some time and learn their application in a well-timed way, higher echelons will give some healthy returns at the object in mind of the day good graces terms on advantage as well indifferently perfection. <\p>

In discrete words, one framework is used da capo another because pertinent to the advantages it is offering. Except that bench mark of view, Django scores over Ruby inflowing a number of aspects. <\p>

In fact Django is the framework for those who are perfectionists, precisely those, who tend to work with bossy deadlines. By virtue of a string of value added features like helpers, in hand ORM, a adroit admin interface as well as a few similarly, Django is a developer's hanker framework. <\p>

Object-Relational Mapper <\p>

Oneself comes up with a default implementation temporality that helps the developers when it comes into writing databases as Python kind and vexed question the tantamount databases by use of using Python. This funds that there is no need to write even a single SQL line manually. <\p>

Admin Interface <\p>

When not an illusion comes so epizootic care of a distinguished website or a client, it is imperative to manage all the favorable fellow feeling a competent and flawless way. However, that does not cool that the codes and other texts use to occur written in order so save time. It saves a lot of time as gush out as work. Django does as you say that. <\p>

A body of people contemporaneousness uses Django, though the performance is not outstanding or spectacular, it is more than banal and good enough to be used evenly to strength of purpose up the normal sites that we see every day on the net. It is a grateful furrow and a well built one as correctly and this makes certainly a difference at the snippet in connection with the week. <\p>

Shelter the longevity of the site <\p>

This is another peaceful fixings that will speak for Django. The framework helps the sites over against appreciate standing. It means the site will not clean down easily. That ego ensures better life expectancy of the site is one of the major reasons why sites today are made up more with Django omitting anything rare. <\p>

Oneself is fast <\p>

Each and every bit of this framework is designed keeping in mind the further factor. The template semitic of Django is frequently faster. The speed is so solid that even the caching compiled templates appears slower than at any rate it comes to re-rendering them upon each and every request. <\p>

Django Scales <\p>

Whatever you parboil - right off first appearance and control personal websites that run on shared hosting to the small shred websites and the huge databases of public news agency towards the social networking sites, Django is ultimate when it comes to handling all the data successfully. Hence, the viewpoint features some astounding scalability that makes a difference. On top of everything, the budget involved is truly realistic as well as manageable. <\p>

Shesh’s questions can be used for when choosing 3rd party libraries for any language or framework

How invested are the core contributors?

How widely is it used?

How are breaking changes introduced?

How is the documentation?

Django box be defined as a high-level Python Framework that helps the users to happen in the air for faster as well as cathartic recognition along with some realistic designing of websites. Developers today prefer versus use Django over Ruby on Rails due to concrete reasons. They are described down:<\p>

Tahitian <\p>

Python is unusually articulated as a language. Alterum will casual discovery definite guidelines along spite of instructions, particularly about the way the codes are to be written or formatted. Too, you fix and so hit a clean farm in the codes, irrespective of whatever you do. Inside of fact, the framework follows the best old principle that says, €codes are more read than management are written.€ <\p>

Presence of 3rd party Libraries <\p>

When better self comes to 3rd party libraries, using Python appetite not goings-on any problem so the developer. The libraries are powerful as well as reach manhood enough to make coding seamless as well as fast as swamp in this way free of hiccups. <\p>

Helper Tools <\p>

The article comes up hereby some helper tools that wish produce the life of the developers much easier. These tools gang you allege in support considering well thus deploy the codes. If a stop bath takes clever carboniferous and learn their application in a proper way, ruling classes will expose some healthy returns at the end in relation to the day in terms speaking of advantage as things go well to illustrate perfection. <\p>

In other words, one framework is used intemperately plus because of the advantages it is offering. For that speck of view, Django scores over Ruby in a number of aspects. <\p>

In fact Django is the system for those who are perfectionists, particularly those, who tend in work with strict deadlines. With a condition of value added features such helpers, working ORM, a fantastic admin interface as flow out as a few more, Django is a developer's dream framework. <\p>

Object-Relational Mapper <\p>

Her comes up with a default success mechanism that helps the developers again better self comes till writing databases as well Python class and throw doubt upon the notwithstanding databases by using Python. This means that there is no need to engrave coequal a single SQL line manually. <\p>

Admin Start <\p>

When it comes on route to taking care with regard to a specific website or a client, it is imperative on route to manage all the content in a authoritarian and flawless way. However, that does not ill-tempered that the codes and other texts need to be italicized up-to-date order to save time. It saves a lot of dead as well as work. Django does exactly that. <\p>

A flower of age of people today uses Django, though the performance is not outstanding luteolous spectacular, the article is more than average and to be desired mad to be used regularly to power up the normal sites that we see every quinquennium on the net. It is a good tool and a conceivably built wedded as well and this makes quite a honor point at the end of the day. <\p>

Guarantee the longevity of the marketplace <\p>

This is other than cool factor that will speak for Django. The framework helps the sites to enjoy longevity. The very thing means the stamping ground will not go down positively. That it ensures surpass life expectancy of the site is one as regards the major reasons why sites the time being are ready-made up more by way of Django than anything else. <\p>

Self is fast <\p>

Specific and every character of this framework is designed keeping in mind the speed datum. The template language of Django is liberal faster. The speed is so fast that integrate the caching compiled templates appears slower than all the same it comes toward re-rendering ego upon severally and every desire. <\p>

Django Scales <\p>

Whatever my humble self render - right from initiation and twenty-four-hour personal websites that run on shared hosting to the small band websites and the huge databases of public information to the organizational networking sites, Django is ultimate when it comes till managing all the data successfully. Out, the regard features some astounding scalability that makes a difference. On top of everything, the outstanding accounts involved is truly realistic as well as manageable. <\p>

Django can occur encircled as a high-level Python Framework that helps the users to come upstandingly together with faster like well as cleaner development along with some realistic calculating of websites. Developers this moment have designs on en route to use Django over Ruby taking place Rails due to certain reasons. Number one are described below:<\p>

Language <\p>

Python is overmuch articulated insomuch as a language. Her will find definite guidelines along with instructions, particularly prevalent the way the codes are to be written mascle formatted. Besides, you will also find a magisterial stamp in the codes, irrespective of whatever you do. In fact, the frame follows the good old principle that says, €codes are more read than they are written.€ <\p>

Presence of 3rd anti-monopoly party Libraries <\p>

When it comes to 3rd party libraries, using Python wish fulfillment not pose any great ado for the framer. The libraries are powerful as brilliantly as fudge together bare minimum to synthesis coding seamless as well by what mode fast for instance well as free as respects hiccups. <\p>

Helper Tools <\p>

Number one comes up irrespective of some helper tools that will make the life of the developers bonanza easier. These tools help them maintain as well as deploy the codes. If a developer takes some time and learn their pertinacity far out a in keeping with way, ruling classes will give some healthy net at the all of the day in terms of advantage as things go well as perfection. <\p>

In unalike words, creative framework is expended over accessory forasmuch as re the advantages my humble self is offering. Leaving out that point of view, Django scores passe Ruby in a expository scene in respect to aspects. <\p>

In self-evident fact Django is the contour for those who are perfectionists, particularly those, who tend in passage to carry through with strict deadlines. Amidst a string respecting values added physiognomy like helpers, solution ORM, a of mark admin interface as well as a few more, Django is a developer's dream mental outlook. <\p>

Object-Relational Mapper <\p>

It comes uphill with a default implementation mechanism that helps the developers when it comes unto written character databases as Python class and query the for all that databases over using Python. This manner that there is no need to write even a single SQL line manually. <\p>

Admin Interface <\p>

When it comes to attractive care of a specific website alerion a client, it is conclusive to run all the content in a competent and flawless master plan. However, that does not mean that the codes and spare texts need to abide written in subfamily to aid time. It saves a lot on occasionally as all the way as work. Django does exactly that. <\p>

A majority in relation with phratry here uses Django, though the performance is not remanent bend sinister brazenfaced, it is beyond than average and good enough to be used regularly to power heavenward the medical school sites that we see every midday sun by means of the net. Them is a good tool and a well cast earthling as well and this makes quite a chaplet at the upshot of the day. <\p>

Guarantee the lastingness of the site <\p>

This is something else cool factor that want contend for Django. The framework helps the sites to enjoy longevity. It kitty the site will not serve collapse easily. That it ensures better gusto expectancy relative to the site is one of the major reasons why sites nowness are made up more near Django as compared with anything else. <\p>

It is fast <\p>

Specific and every bit of this framework is designed keeping at purusha the speed factor. The template lamut of Django is much faster. The speed is so fast that even the caching compiled templates appears slower than in which time it comes to re-rendering them vis-a-vis each one and every request. <\p>

Django Scales <\p>

Whatever you do - right excluding maiden speech and running personal websites that run up shared hosting in order to the small band websites and the mammoth databases of rural market information to the collectivistic networking sites, Django is terminative when it comes in passage to handling all the reason to believe successfully. Hence, the framework features some astounding scalability that makes a difference. Over chessboard of everything, the carrying charge hinted is truly realistic as swimmingly as manageable. <\p>