Come on, it's not easy for big factories to do projects!

Unveiling the R & D process of first-line large factories

Hello everyone , I'm fish skin .

A lot of kids who haven't worked are curious ： What is the process of doing a project in an enterprise ？ Especially the projects with millions of users in big factories , What's the difference between learning programming and doing projects ？

To be honest , It's a big difference ！

Develop your own projects. It's on your own , Control your own destiny , It's not going to bring down the team ; But in the enterprise, the development project is the starting point , We are grasshoppers on the same rope , Everyone affects the whole project .

I have practiced in several companies myself , Have to say , The R & D process of big factories is also very different from that of other companies .

therefore , For most students , If you haven't worked in a big factory , I don't know much about R & D .

So today I want to reveal the R & D process of Dachang project , Help you open up ideas .

Just before, some comrades questioned that my daily work is only to write code and fish ？！ This article is a response , Let him understand , Doing projects in large factories , It's not just code ！

The R & D process of big factories revealed

In order to regulate the team 、 Ensure the progress of the project , The R & D process of large factories is usually complicated .

It can be divided into many stages , Use a mind map to summarize ：

R & D flow chart of first-line large factories

It should be noted that , The above stages are not carried out completely from top to bottom , There may be intersections between stages , such as Technology selection Actually in design phase We should consider .

More than a year of formal work , I have also experienced the complete R & D process of many projects . From my perspective , Let's go through it quickly ~

（ To make the content more interesting , The following story is fictional ）

Demand stage

Today is Monday , Yupi came to the company on his small electric car as usual , Little imagine , Waiting for him is the beginning of a nightmare .

Demand arises

Forenoon ten a.m. , Product girl finds fish skin , Tell him ： When our system goes online , The user said that many functions are not easy to use , It needs a big change .

The boss also found fish skin , Tell him ： I opened the page today and loaded it for more than ten seconds , Is the performance of our system too bad ！

Fish skin thought ： Vomit , Be finished ！ I guess we need to do a new project , It's time for another meeting .

Sure enough , It was not long before , A message pops up on the screen “ Welcome to the conference ” Invitation .

Requirements review

Next morning , Boss 、 product 、 test 、 Several development brothers and fish skin came to the conference room together , Specifically discuss the requirements mentioned yesterday Is it reasonable? 、 Do you want to do ？

Product girl opens the document , Speaking of ： This issue , We need to do these needs , Let me talk about it in detail , Let's evaluate if there are any problems .

Demand analysis

Next , The product girl is talking to the screen 、 Crazy output , Next to the development of big brother can not sit .

Big brother development ： This demand is unreasonable ！

product ： Why not ？ That's what users need ！

Big brother development ： That's true. , It can't be realized ！

So we started the classic product development war ...

And the fish skin is hiding in the corner How to do this demand , After a while , Put forward a kind of change low 、 Achieve fast solutions , Put down the war .

scheduling

Make sure the demand is reasonable 、 After that , Product sister asked ： When will this demand go online ？

Big brother development ： I'm busy this week , Next week .

product ： Users may be in a hurry , This week ！

Big brother development ： That's true. , I can't finish it ！

So we started the classic product development war ...

Fish skin ： Or we can break this requirement down into functions A And function B, This week I'll start with the features A Did , function B It's scheduled for next Tuesday's test , Go online next Thursday ？

That's it , We arranged the planned completion date of the requirements one by one .

design phase

Finally, the meeting is over , Look at the time , It's time to get off work ！

alas , The needs are discussed , The work of the product is to complete some , But the work of fish skin is just beginning .

In a hurry to start writing code ？

No , Thinking about how to write code is more important than writing code .

Architecture design

Fish skin open the document writing software and drawing software , Start hacking the whole system , From the whole to the part , Design the hierarchical structure of the system in turn 、 Interface and communication mode of interaction between layers 、 What important modules are included in each layer 、 What kind of physical deployment mode the module chooses, etc .

Well known framework Dubbo Architecture design

Outline design

After writing the architecture design , Fish skin began to write to the product sister PRD（ Product requirements document ）, Analyze requirements , And then it's still from the whole to the part , First sort out the functional modules needed by the system , Then analyze the sub modules in each functional module .

Compared with abstract architecture design , Outline design is more closely related to requirements , It's a refinement of architecture design .

For example, we can see , You're going to build a building , Architecture design is to consider from the whole , How many floors are there altogether 、 How to connect the pipes on each floor 、 There are several households on each floor 、 How to lay the foundation, etc ; And the outline design is to consider how to divide each family's suite , Where is the living room 、 Where is the bathroom .

In many cases , Outline design and architecture design may be carried out in one document , The division is not clear .

Detailed design

After thinking about the functions of the system , Fish skin began to analyze how to realize each function , Which algorithms are used 、 What details should we pay attention to .

Scheme alignment

After writing the design document , At the next meeting , Fish skin and other developers （ front end 、 Back end, etc ） Let's have a discussion about our own design , Ultimately, there is a unified solution , Then we should divide the work and do it .

Test case design

In order to ensure the normal and stable function of the system , Test students （ Or call it QA） It's very important , The test is not just a few clicks on the web page as we do our own projects ok 了 .

In a big company , In order to ensure the coverage of the test 、 Improve test efficiency , Generally, test cases are designed , such as ： The user clicks “ Sign in ”, No data was sent , The expected result is to warn the user to enter a user name and password .

Test case management

After the test case is designed , We need other students to judge and check together , Instead of just giving it to test students . Because it's easy for a person to ignore a lot of test details , It's better to let the developers who are more familiar with the code to help supplement .

Fishskin also wrote a few test cases that might be missed in the test , Confirmed with the test students , Try to expose problems in the test phase rather than online .

R & D preparation

I've been writing design documents for almost a week , Finally ready to start building the project . But before that , There are still some preparatory work to be done .

Technical pre-research

Now technology is developing too fast , New technologies emerge in endlessly , So the fish skin first investigated the technologies that need or may need to be used in the project .

Technology selection

Through research , Fish skin has several technologies that can meet the needs , But he started to get tangled ： So many technologies , Which one should I use ？ Yes, it is SSM Frame or Play What about the framework ？ use guava Package or Apache Commons Well ？

Fish skin opens the document writing software again , Start comparing different technologies , A headache , There are too many factors to consider in technology selection , such as ：

• From a technical point of view ： performance 、 Ease of use 、 stability 、 Mainstream and Ecology 、 Document detail
• Combined with the team ： Team members' familiarity with technology 、 Control （ Is there anyone who is proficient in this technology ）
• Combined business ： Whether to adapt to the scale of business （ stand-alone or Microservices ）、 Adapt to the business （ Read more 、 Write more or More analysis ）

For key projects , I'm not sure about the selection of fish skin , So after writing your own selection document , With colleagues and Leader Discuss together , Finally confirmed .

Resource request

After confirming the technology , You have to apply for resources . Like fish skin MySQL database , But this MySQL From where ？

In the past , Fish skin is to buy a cloud server , Build yourself MySQL. But in business , Generally, there is a platform for centralized management and allocation of resources , Go directly to the platform and fill in the budget 、 Wait for the leader to approve 、 Just wait for the resources to be distributed . Never use your own or buy an external server to deploy the project , unsafe ！

Fish skin directly applied to 2 More than 10000 years of cloud database , It's really cool .

Environmental preparation

After applying for database and other resources , The skin is as like as two peas in the application machine version , Then you can connect it directly .

Project initialization

When the environment is ready , Because it's a new project , Fish skin to do a minimum runnable initialization project Demo, Use The scaffold Automatic code generation , Instead of creating new files from scratch 、 Repeat the code by hand .

Dependent installation

After generating the project code , Fish skin uses bag management tools （ front end yarn、Java Maven / Gradle etc. ） Auto install dependency , And then the project Demo You can run it ！

R & D stage

After the preparation is finished , This is the programmer's most familiar part of writing code , It's also a favorite part of fish skin .

Because you need to be calm when designing a project before 、 Think about , I can't do it while listening to music ; And after the design , It's clear what to do , It's very easy to write code , At most, there are some pits , Search the Internet to solve it .

Local development

When developing , Generally, fish skin will write code locally first , By configuring the hot update tool , Realize automatic recompilation and packaging when code is updated , Instead of manually restarting the project , Greatly improved development efficiency .

by the way , Enterprise development will use version control system , such as Git, Remember to create your own branch before development , Develop... On this branch .

Remote development

Now there is a more popular way of remote development , That is, you can edit remote files just like you edit local files , Directly modify the code on the server . Generally, each of our R & D students has his own development machine , Through remote development, the trouble of repeated deployment and debugging is saved , Increase of efficiency . It's usually used VSCode Development tools such as , Install the remote development plug-in .

Code optimization

When fish skin is writing code , Always keep the habit of actively optimizing your code , Focus on the spatiotemporal complexity of code ; And when there's a lot of duplicate code , I will think of ways to abstract into functions or use design patterns . I wrote a special article to share my programming habits before ： My little stubbornness when I write code .

unit testing

Be careful ！ Don't think it's the job of testing students when you hear the test , Developers also need to write small granularity tests to be responsible for their own code .

Fish skin generally writes unit tests for each database read-write function and business logic function , image Java In general, it is used JUnit Tools such as , You can also use Jacoco Generate test coverage reports . Every time you change the key code , You have to run a unit test , Prevent accidental mistakes .

Jacoco Test coverage reports

Development joint commissioning

Fish skin finally wrote the back-end code , Self test completed , Here's how to package and build the written code , Then publish the executable package to the test server , Joint debugging with front-end students , Let him ask for my interface , Verify that the functions of the system are available .

Test verification

After the joint debugging of fish skin and front end , Told the test and product students .

Testing and verification is a crucial link in an enterprise , Even the last line of defense . The purpose of the test is to find Bug, Try to find problems in the system , Kill them in the test phase .

In the enterprise , There are many types of test validation .

Integration testing

Integration testing is more granular than unit testing , Is to put multiple modules or code units together , Verify the integration and call relationship between modules .

Because the execution of a single function may be normal , But combining multiple functions and calling them in sequence , There may be problems .

For example , We have a bread eating system ：

function A： Little fish eat a piece of bread

function B： Xiao PI eats a loaf of bread

Only one bread at a time , Perform functions independently A and B It's all allowed . But if the two work together , The function that is executed later will report an error .

The system test

System testing is more granular than integration testing , The test object is the whole system , Not just software , It may also cover testing of hardware .

Product experience

In addition to testing students to verify the availability of the system , The product sister also needs to experience whether the function meets the expectation 、 Is it easy to use . Most of the time , The product will make suggestions for modification during the experience , Development may need to make some more changes .

The acceptance test

The test and product girl finally said that there was no problem , That's the last step , Give the whole product or function to the end user to experience . Boss The user said no problem , It's true. No problem ！

Submission phase

After the system is OK , The fish skin can release the code to the remote warehouse , In general use Git and SVN Wait for version control system .

Submit code

Fish skin first triggers code submission locally （git commit）, In order to ensure the standard , In large projects, you usually use the submit detection plug-in , Prevent you from submitting the wrong code .

Code push

The next step is to push the local submission to the remote branch with the same name . Generally, large factories have push detection tools , Detect code errors 、 Cyclomatic complexity 、 Code specification, etc , Just like the submit test , To prevent you from pushing wrong or nonstandard code .

Merge request

After the code branch is pushed to the remote , Fishskin initiated a branch merge request （MR）, I want to merge the code of this branch into the main branch （ No problem code ）.

Initiate a new merge request

Code review

It's not that you can merge directly when you initiate a merge request , And code review , namely CR.

There are two ways of censorship ： Human audit and machine audit .

I believe a lot of students know about the human trial , It's usually up to your superiors and other project leaders to read and comment on your code , If you think it's OK, just Approve（ adopt ）, Otherwise, call back to modify .

What is the machine audit ？ In fact, the machine automatically detects whether your code meets the specifications , Whether it can be built automatically , It's usually assigned by the project leader , It can help to find some problems that are difficult to find manually .

When I first came into contact with a new project , Fish skin is often tortured by machine trials , Often be prompted some inexplicable code problems , For example, the plus sign has to change lines , Blank lines should be added at the end of the file line . But later, after paying attention to coding habits , It's a natural adaptation , It is indeed good. .

Release stage

After passing the code review , Fish skin project code can be released online .

Pack to build

The traditional way to go online is for developers to pull code from the official server , Then install the dependencies , And then package and build the code through tools , Get the deployment package , adopt Nginx、Tomcat、Docker And so on .

But it's inefficient , There's a lot of repetitive work . So large factories are generally built with automation , image Jenkins、 Various CI / CD Tools etc. . The code is merged into the main part , The machine packages the code into the final deployment package .

pre-release

In order to prevent online problems , Generally, we will deploy the project in the pre release environment first , And see if it works .

Official release

After the pre release test is normal , The fish skin has finally come online . Large projects are usually deployed on multiple machines , So it's impossible to publish the deployment package one by one .

Usually companies provide visual publishing platforms , Click on the publishing machine （ It's usually gray first , Choose a small number of machines , Release it in full ）, Click one button to publish , After the approval of the project manager , Let the machine deploy it automatically ！

follow-up

Fish skin once naively thought that after the project went online , You can have a good sleep . But then it turned out , After the project goes online , You also need to be alert . Although it has been tested , But from time to time there is still a little unexpected Bug, It's still a test of mentality .

Let's see when it's online , What did fish skin do ？

Monitoring operation and maintenance

Fish skin will check the monitoring panel of the project regularly , Observe the operation of the project , The load of the machine, etc .

Statistical analysis

Fish skin added some logs to the code , You can use ELK Wait for the log collection visualization platform to analyze these logs , So as to perceive the user's behavior , Further optimize business and systems .

For example, I will count the user execution SQL Time consuming to query , Slow for high repetition rate SQL Targeted optimization .

Event feedback

sometimes , The user can't describe it clearly Bug, And history Bug It's not easy to find . So there is usually an event feedback platform inside the company , Products and other internal students are receiving Bug when , Will release a Bug event , Detailed description Bug Time of appearance 、 condition 、 Details, etc , It is convenient for us to develop, analyze and deal with problems .

Event feedback platform

Document precipitation

New features and projects are launched every time , Fish skin will document the background of the project 、 design scheme 、 Development process and some pitfalls , It is convenient for other students to understand the project , This is very important ！ Benefit others and benefit oneself .

I've shared my document writing skills ： How to write a good document ？

Iterative optimization

Last , The end of one requirement is often just the beginning of another . Like fish skin's latest follow-up project , Finish the first phase and do the second phase , The second issue has not been finished, and the third issue is coming ; And take the time to optimize the previous code , It's a long way off , There's no hope ！

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That's what we're sharing , After reading this article , Welcome to my previous article ： Dachang secret ！30 A package to improve the team's R & D efficiency , Learn more about big factory Technology .

Finally, I'll send you some more Help me get to the big factory offer Learning materials ：

ran , leave 6T Resources for ！

Welcome to I started from 0 I began to learn Tencent's programming experience by myself , No more confusion ！

I studied computer for four years , Mutual encouragement ！

I'm fish skin , give the thumbs-up It's still a request , I wish you all the best 、 Make a fortune 、 Universiade .