困惑如何建立一个多项目的SBT项目

Question

I'm using sbt .13 here.

I have this so far:

import sbt._
import Keys._
import play.Project._

object ApplicationBuild extends Build {

  val appVersion = "1.0"

  resolvers += "local maven" at "/Users/blankman/.m2/repository/"

  val commonDependencies = Seq()
  val modelDependencies = Seq(
    "com.typesafe.slick" %% "slick" % "2.0.1",
    "org.slf4j" % "slf4j-nop" % "1.6.4"
  )

  val serviceDependencies = Seq(
    "com.typesafe.slick" %% "slick" % "2.0.1",
    "org.slf4j" % "slf4j-nop" % "1.6.4"
  )

  val webDependencies = Seq(
    //"org.apache.tomcat" % "tomcat-jdbc" % "8.0.3",
    "mysql" % "mysql-connector-java" % "5.1.30",
    "com.typesafe.slick" %% "slick" % "2.0.1"
  )


  lazy val common = Project(
    id = "app-common",
    base = file("app-common"),
    dependencies = commonDependencies
  )

  lazy val models = Project(
    id = "app-models",
    base = file("app-models"),
    settings(modelDependencies: _*)
    )
  ).dependsOn(common)

  lazy val services = Project(
    id = "app-services",
    base = file("app-services"),
    settings = Seq(
      libraryDependencies ++= serviceDependencies
    )
  ).dependsOn(models, common)


  lazy val web = play.Project("app-web", appVersion, webDependencies,
                        path = file("app-web"))
                      .settings(playScalaSettings: _*)
                      .dependsOn(services)

}

This doesn't work. For example, if I go into:

project app-models

and try and compile, it says compile isn't valid or something.

I'm really confused how to set up a project. What is the correct way?

Looking at this slide #10 here http://jsuereth.com/scala/2013/06/11/effective-sbt.html it says I can do:

lazy val web = (
  Project("app-models", file("app-models"))
  settings(
     libraryDependencies += modelDependencies
  )
)

But when I do this I get an error also.

I basically have a few projects inside of sbt:

common
models
services
web (which is play)

• models depends on commons
• services depends on commons + models
• web depends on services

Can someone help me get this to work?

Answer 1

There are a few issues I found in your build definition, but since you bought up Josh's Effective sbt talk, I think we should go whole hog on the style.

Effective sbt

Here are the files.

project/build.properties

sbt.version=0.13.2

project/play.sbt

val playVersion = "2.2.2"

resolvers += Resolver.typesafeRepo("releases")

addSbtPlugin("com.typesafe.play" % "sbt-plugin" % playVersion) 

project/commons.scala

import sbt._
import Keys._

object Commons {
  val appVersion = "1.0"

  val settings: Seq[Def.Setting[_]] = Seq(
    version := appVersion,
    resolvers += Opts.resolver.mavenLocalFile
  )
}

project/dependencies.scala

import sbt._
import Keys._

object Dependencies {
  val slickVersion = "2.0.1"
  val slick = "com.typesafe.slick" %% "slick" % slickVersion
  val slf4jVersion = "1.6.4"
  val slf4jNop = "org.slf4j" % "slf4j-nop" % slf4jVersion
  val mysqlConnectorVersion = "5.1.30"
  val mysqlConnector = "mysql" % "mysql-connector-java" % mysqlConnectorVersion

  val commonDependencies: Seq[ModuleID] = Seq(
    slick,
    slf4jNop
  )
  val modelDependencies: Seq[ModuleID] = Seq()
  val serviceDependencies: Seq[ModuleID] = Seq()
  val webDependencies: Seq[ModuleID] = Seq(
    mysqlConnector
  )
}

build.sbt

import play.Project._
import Dependencies._

lazy val appCommon = (project in file("app-common")).
  settings(Commons.settings: _*).
  settings(
    libraryDependencies ++= commonDependencies
  )

lazy val appModels = (project in file("app-models")).
  settings(Commons.settings: _*).
  settings(
    libraryDependencies ++= modelDependencies
  ).
  dependsOn(appCommon)

lazy val appServices = (project in file("app-services")).
  settings(Commons.settings: _*).
  settings(
    libraryDependencies ++= serviceDependencies
  ).
  dependsOn(appModels, appCommon)

lazy val appWeb = (project in file("app-web")).
  settings(Commons.settings: _*).
  settings(playScalaSettings: _*).
  dependsOn(appServices)

notes

settings parameter vs settings method

For models and services , you're passing in settings sequence into Project(...) constructor, so the default settings are likely not loaded. You can pass in the default settings manually, or use settings(...) method on Project , which I would recommend.

lazy val appModels = (project in file("app-models")).
  settings(
    libraryDependencies ++= modelDependencies
  ).
  dependsOn(appCommon)

Josh uses postfix notation using parenthesis, but I prefer using dot notation for this, so that's a slight deviation from the talk.

libraryDependencies ++=

As the above example, you have to pass modelDependencies to libraryDependencies . You had it calling directly into settings .

resolvers

The resolvers setting is not passed into anything, which likely is not correct.