Environmental preparation - Engineering Management

explain

• Project management is project management ,go The language provides workspace management , Source code management , The third party relies on specifications such as library management .
• go Is the engineering language , Not as free as college language , Some specifications have been made for project management .

work area （workspace） management

• go Language programming , It is not easy to create a directory as a working directory , Because it depends on file search and intermediate 、 Generation of target file , And the installation of executable files ,go There are certain specifications for the directory structure of the workspace and the designation of the workspace .
• Of course, if the project has only a single source file or multiple files, but the import package path is written to the absolute path, it can also be compiled , But this is not recommended .

View and set up

• go The default workspace will be set after the environment is installed , And create a default directory structure under this directory ,linux for ~/go/.
• go adopt GOPATH The environment variable sets the workspace path , It can be modified manually , However, you need to manually create these subdirectories after modification .
• see

go env GOPATH

• Set up

export $GOPAHT=/xxx/xxx

• Be careful ：GOPATH You can set multiple , But if you set multiple paths , Need to set up GOBIN Environment variables to determine which directory the executable is placed in .

Directory structure

• The workspace contains 3 Subdirectory .

1. src Catalog ： Store project source code , A project is divided into a subdirectory , go get The downloaded third-party packages are also placed in this directory .
2. pkg Catalog ： Storage via go install Command to build the installed “.a” The archive .
3. bin Catalog ： And pkg Similar directory , Through go install After the command is installed , Save by Go Command source file generated executable file .

Develop and improve

• GOPATH The mechanism is primitive and simple , In the process of development, it shows some deficiencies , for example ：

1. The code must be in GOPATH The next path src Directory , Otherwise , Importing the package in the project will prompt that it cannot be found .
2. Dependent packages need to be managed manually , No version number information .
3. …

• The official management mechanism is also improving , Experienced GOPATH、go vendor, At present, the latest and mainstream official mechanism is go mod.

Source code and third-party dependency library management

• go Both source code and third-party dependency libraries are organized and managed in the form of source code packages .

Engineering example

1. Create a project

• Early creation of a new project needs to be done in the workspace src Under the table of contents , But with go mod The mechanism does not need , Can be created in any directory .
• Create a project root directory , for example ：example, Put the code in the root directory .

2. Compile and install

• The compilation needs to be executed under the root directory of the project “go build” command ,go The compiler will automatically derive the dependencies , The compiled executable name is the project name .
• The installation needs to be executed in the same directory “go install”,go The compiler will place the generated file in the... Of the workspace bin and pkg Next .
• A single file program can also compile the file directly , as follows ：

go build xxx.go