Use the Mill Scalalib framework to achieve elegant code packaging and organization
Use the Mill Scalalib framework to achieve elegant code packaging and organization
Mill SCALALIB is a powerful construction tool that is designed for SCALA language.By using Mill, developers can encapsulate and organize code in a simple and elegant way to improve the maintenance and scalability of the project.
When using the Mill SCALALIB framework, you can use the following methods to achieve elegant code packaging and organization:
1. Definition of tasks and goals: Mill allows developers to organize code by defining tasks and goals.The task is a set of operations, such as compilation, testing or packaging.The goal is the input or output of the task.By defining clear tasks and goals, the code can be decomposed into a reusable module to improve the organizationalability of the code.
The following is a simple example, showing how to use Mill to define a compilation task:
scala
import mill._
import mill.scalalib._
object MyBuild extends ScalaModule {
def compile: Target[PathRef] = T {
scalaVersion("2.13.1")
val src = T.sources{ millSourcePath / "src" }
T{
scalac
.compile(
src().map(_.path),
compilerClasspath().map(_.path),
T.dest / "out"
)
.map(PathRef(_))
}
}
override def allSources: T[Sources] = T.sources {
millSourcePath / 'src
}
}
In the above example, we define a task called `Compile`, which is responsible for compiling the source code of the project.`Compile` Mission defines the input and output of the task: The input is the project source code path, and the output is the compiled target path.
2. Dependent management: Mill support dependency management, and can declare and manage other project dependencies in the project.By defining the correct dependence relationship, the organization of the code can be clearer and ensure the correct compilation and construction of the project.
The following is an example that shows how to define project dependence in mill:
scala
import mill._
import mill.scalalib._
object MyBuild extends ScalaModule {
def compile: Target[PathRef] = T {
// Compile code
// ...
}
def test: Target[Unit] = T {
// Run the test
// ...
}
def packageJar: Target[PathRef] = T {
// Packing items generate jar file
// ...
}
// Definition dependency relationship
override def allDeps: Seq[JavaModule] = Seq(
"org.scala-lang" % "scala-library" % "2.13.1",
"com.google.guava" % "guava" % "30.1-jre"
)
}
In the above examples, we define a scalamodule called `mybuild`, and declare the project dependencies in the` ALLDEPS` method.In this way, when compiling, testing or packing items, Mill automatically analyzes and downloads the dependent items required.
3. Combination and order execution of tasks: Mill provides a powerful task combination and sequential execution function, which can perform multiple tasks in order, or selectively execute tasks according to needs.This mechanism makes the encapsulation and organization of code more flexible and elegant.
The following is an example that shows how to use mill combinations and sequential execution tasks:
scala
import mill._
import mill.scalalib._
object MyBuild extends ScalaModule {
def compile: Target[PathRef] = T {
// Compile code
// ...
}
def test: Target[Unit] = T {
// Run the test
// ...
}
def packageJar: Target[PathRef] = T {
// Packing items generate jar file
// ...
}
// Define the task combination and order execution
def buildPipeline: Target[Unit] = T {
compile()
test()
packageJar()
}
}
In the above example, we define a task called `Buildpipeline`, which calls the mission of` Compile`, `test` and` Packagejar`.By calling the `Buildpipeline` task, all these tasks can be performed at one time.
Through these methods, the Mill SCALALIB framework can be used to achieve elegant code packaging and organization.Reasonable use of Mill's task and target definition, dependency management, and task combination and order execution functions can improve the maintenance and scalability of the code, while improving development efficiency.
