Devops integration - environment variables and building tools of Jenkins service

One 、 environment variable

Environment variables can be seen as pipeline And Jenkins An interactive medium . such as , Can be in pipeline Pass through BUILD_NUMBER The variable knows the current number of builds for the build task . Environment variables can be divided into Jenkins Built in variables and custom variables .

1.1、Jenkins Built-in variables

stay pipeline Execution time ,Jenkins Through a named env Global variable of , take Jenkins The built-in environment variables are exposed .
Default env The properties of can be directly in pipeline I quote ; There are three ways to quote ：

1. ${env.BUILD_NUMBER} Mode one , Recommended
2. $env.BUILD_NUMBER Mode two ,
3. ${BUILD_NUMBER} Mode three , It is not recommended to use

Let's briefly introduce some variables that are often used in practical work .

1. BUILD_NUMBER： Construction number , Cumulative number .
2. BRANCH_NAME： Multiple branches pipeline Project support .
3. BUILD_URL： The currently built page URL.
4. GIT_BRANCH： adopt git This variable is only available for projects built from the pulled source code .

1.2、 Customize Pipeline environment variable

When pipeline When it gets complicated , We will have the need to define our own environment variables . declarative pipeline Provides environment Instructions , Convenient custom variables .
in addition ,environment Instructions can be in pipeline In the definition of , Represents that the variable scope is the entire pipeline; It can also be in stage In the definition of , Representative variables are only valid at this stage .
If in environment The variables defined in are the same as env Duplicate variable names in , Then the value of the variable with the same name will be overwritten .

1.3、 Custom global environment variables

occasionally , We need to define some global cross pipeline The custom variable for .<