sbt - "buildBase"可以指向 SBT 中当前项目之外的目录吗？

Question

假设我有一个现有的(旧的)代码库，并且我想要演示如何使用 SBT 编译它的侵入性最小的方式。我想以这样一种方式完成它，即包含代码库的根目录的文件结构完全不受影响。这意味着 project/Build.scala将需要在实际项目之外。另外，请记住，由于现有项目具有非标准布局并且在非托管依赖项上使用了很多，因此需要完成相当多的配置(例如设置 unmanagedSourceDirectories、unmanagedJars 等)

考虑下面的示例布局:

/opt/workspace
        |
        +- existing-codebase
        | |
        | +- module1
        | | |
        | | +- src
        | |
        | +- module2
        |   |
        |   +- src
        |
        +-  sbt-demo-build
          |
          +- project
            |
            +- Build.scala

另外，假设我设置了以下环境变量:

CODE_HOME=/opt/workspace/existing-codebase

那么，需要进入 Build.scala表示构建基础 ( buildBase ?) 是 /opt/workspace/existing-codebase而不是 /opt/workspace/sbt-demo-build
我尝试设置 baseDirectory关键，但 SBT 只是失败了:

java.lang.AssertionError: assertion failed: Directory /opt/workspace/existing-codebase/module1 is not contained in build root /opt/workspace/sbt-demo-build

这是 DemoBuild我在项目中使用:

import java.nio.file.{Paths, Files}
import sbt._
import Keys._

object DemoBuild extends Build {
  val codeHome = Paths.get(sys.env("CODE_HOME")).toAbsolutePath.
                       toRealPath().normalize().toFile
  ...
}

我能想到的最好的比喻是 Ant 的 basedir project 中的属性元素 - 这个概念在 SBT 中不存在(或者它只是没有正确暴露)？

更新:

经过一番挖掘，我发现了一个名为 xsbti.AppConfiguration 的东西。这似乎对应于一个名为 sbt.Keys.appConfiguration 的设置.我试图覆盖使用:

  appConfiguration ~= { cfg =>
    new AppConfiguration {
      def arguments(): Array[String] = cfg.arguments()
      def baseDirectory(): File = codeHome
      def provider(): AppProvider = cfg.provider()
    }
  }

但是得到了相同的 AssertionError。然后，我找到了一些 official docs这可能会有所帮助，所以我将研究这些作为下一步

Answer 1

选项1
使用/opt/workspace作为 SBT 项目的项目目录。使用它，因为你打算使用 /opt/workspace/sbt-demo-build .
选项 2
在 build.sbt 中使用以下构建定义它在当前项目目录之外定义了两个 SBT 模块。

lazy val root = project in file(".") aggregate (module1, module2)

lazy val module1 = ProjectRef(file("../existing-codebase/module1"), "module1")

lazy val module2 = ProjectRef(file("../existing-codebase/module2"), "module2")

它假定 module1和 module2是 SBT 项目和 root项目聚合它们，因此在 root 中运行命令 will also run it on the aggregated projects .
选项 3
在 Unix 上，使用 ln -s 符号链接(symbolic link)项目在构建根目录之外。

jacek:~/sandbox/so/andrey-workspace/sbt-demo-build
$ ln -s ../existing-codebase/module1 .
jacek:~/sandbox/so/andrey-workspace/sbt-demo-build
$ ln -s ../existing-codebase/module2 .
jacek:~/sandbox/so/andrey-workspace/sbt-demo-build
$ tree
.
├── build.sbt
├── module1 -> ../existing-codebase/module1
└── module2 -> ../existing-codebase/module2

2 directories, 1 file

使用以下 build.sbt其中定义了项目。

jacek:~/sandbox/so/andrey-workspace/sbt-demo-build
$ cat build.sbt
lazy val root = project in file(".") aggregate (module1, module2)

lazy val module1 = project

lazy val module2 = project

在 SBT 控制台中， projects , project和 run完美地工作:

jacek:~/sandbox/so/andrey-workspace/sbt-demo-build
$ sbt
[info] Loading global plugins from /Users/jacek/.sbt/0.13/plugins
[info] Set current project to root (in build file:/Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build/)
[root]> projects
[info] In file:/Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build/
[info]     module1
[info]     module2
[info]   * root
[root]> module1/run
[info] Running Hello
Hello from module1
[success] Total time: 1 s, completed Jan 11, 2014 9:40:03 PM
[root]> project module1
[info] Set current project to module1 (in build file:/Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build/)
[module1]> run
[info] Running Hello
Hello from module1
[success] Total time: 0 s, completed Jan 11, 2014 9:40:20 PM
[module1]> project root
[info] Set current project to root (in build file:/Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build/)
[root]> show baseDirectory
[info] module1/*:baseDirectory
[info]  /Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build/module1
[info] module2/*:baseDirectory
[info]  /Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build/module2
[info] root/*:baseDirectory
[info]  /Users/jacek/sandbox/so/andrey-workspace/sbt-demo-build