Monomer application concept

（1） Concept ： All functions are packaged together , The application is mostly a war Package or jar package .

（2） benefits ： Easy to develop 、 test 、 Deploy , It is suitable for trial and error in the early stage of the project .

（3） Disadvantage ：

• As the project gets more and more complex , The team is expanding . The disadvantages show up .
• High complexity ： Lots of code , 100000 lines , Million line level , If you add a small function , It will bring hidden dangers of other functions , Because they're together .

• Technical debt ： Mobility , No damage, no repair , Because I dare not repair .

• Continued deployment is difficult ： Because it is full application , Change a small function , All deployed , Will cause irrelevant functions to be suspended . Compiling and deploying online takes a long time , Dare not deploy casually , This leads to low deployment frequency , In turn, there are many functional modifications between the two deployments , The more afraid to deploy , A vicious cycle .

• Poor reliability ： A little problem , It may cause the whole application to crash .

• Expansion is limited ： Can only be extended as a whole , Cannot expand as needed , Cannot be based on compute intensive and IO Make appropriate distinction between intensive .

• Stifle innovation ： Monomer application is to solve all problems with one technology , It's not easy to introduce new technology . But in the rapid development of the Internet , The trend to adapt is ： Do the right thing in the right language . For example, in monomer applications , A project uses spring MVC, I want to change it into spring boot, High switching cost , Because it's possible 10 ten thousand , Millions of lines of code have to be changed , Microservices can be easily switched , Because every service , Simple function , Less code .