I have a simple Scala command line App that I want to package using SBT.
object Transform extends App {
val source = scala.io.Source.fromFile(args(0))
...
}
I can't seem to find anything in the SBT docs or an online example of a SBT configuration/command that would allows me to create a standalone executable jar (java -jar ...) with the appropriate manifest and dependencies included.
I did find SBT Assembly, but it looks to be a plugin for SBT < 0.13.5.
sbt-onejar was created for exactly this use case.
Related
Is there any way to run sbt commands with only a jar instead of a project?
I've been having issues using scopt with java or scala commands, and it only seems to work with sbt.
Ideally something like
sbt --jar <jar name>/"run-main <options"
You'd probably want to package everything up into something you can execute. One possibility would be to create a fat jar using something like sbt-assembly.
Once you've built your jar, you can then:
java -jar /path/to.jar --your-options
Take note that at this point you can only do what would have been the equivalent of sbt run-main with the jar. You cannot of course invoke any of the other sbt commands on the jar created.
I want to migrate our build from maven to SBT, so now I work separatedly on Build.scala file. However I don't benefit from any syntax highlighting (that is quite obvious, I don't have SBT in my classpath). What is the correct way to get SBT to my classpath, adding sbt-launch.jar does not seem to help.
IntelliJ 13 has built-in SBT support; if you're running a lower version, then you can have a look at their sbt plugin.
There's also an sbt plugin on github for generating idea project files. I've had success with running the gen-idea task it provides.
Run sbt gen-idea. It will create a "YOUR_PROJECT_NAME - build" project within your main project (for whatever your YOUR_PROJECT_NAME happens to be). Under the project folder of the build project, I was able to write a Build.scala with the following code:
import sbt._
object Build extends Build {
}
The SBT Build trait is recognized just fine. I'm running IntelliJ 13 build #IU-133-696, Scala plugin 0.30.378.
Eventually what I did is finished to write my build.sbt stub, and opened a project with it. Now everything seem to work.
I'm using *.scala files in the project folder for configuring my SBT project. I'm using IDEA12 with the Scala Plugin and sbt-idea for generating the project. After calling gen-idea in the SBT shell, everything works fine except for one thing. When I click go to declaration on some method in my project code, IDEA shows me how it is implemented (redirects me to the library sources). But when I'm trying to "inspect" SBT's internal sources it shows me something like this:
def settings: Seq[Setting[_]] = { /** compiled code **/ }
How can I attach SBT sources to my IDEA project?
I'm using SBT 0.12.3.
In SBT there are two command which may interest you:
update-classifiers - will download all sources and documentation for all libs in your project
update-sbt-classifiers - downloads sbt sources and docs
This will download all the sources you need. To make an IDEA project with them just call gen-idea sbt-classifiers.
If you don't want to call each time this commands for re-generating you project, you should add something like this to your build.sbt: addCommandAlias("make-idea", ";update-classifiers; update-sbt-classifiers; gen-idea sbt-classifiers").
As of sbt version 1.2.8, the command is changed to:
sbt updateClassifiers - to download all sources and docs
sbt updateSbtClassifiers - to download sbt sources and docs.
I am developing a sbt plugin. In this plugin I generate some new scala sources packaged in a sbt project. Then I need to compile these new files programaticaly so that I could add the generated class in my classLoader.
I do not find any way to compile programaticaly sources from a given sbt project path (and eventually from a classLoader) in the sbt API, something as simple as the sbt command (sbt compile) line would be very convenient, something like:
XXX.compile(path/to/sbt/project)
Thanks
I suggest you have a look at sbt-boilerplate which is an sbt plugin that generates code, works well and is really simple.
Here's a link to the file that you probably want to take a look at
The answer: Making stand-alone jar with Simple Build Tool seems like what I need, but it did not have enough information for me, so this is a followup.
(1) How do I adapt the answer to my need? I don't understand what would need to be changed.
(2) What command do I run to create the standalone jar?
(3) Where can I find the jar after it has been created?
What I've tried:
Pasting the code in the linked answer verbatim into my: project/build/dsg.scala file. The file now has a
class ForkRun(info: ProjectInfo) extends DefaultProject(info)
(from before, used for running projects in a separate VM from SBT) and the new:
trait AssemblyProject extends BasicScalaProject
from the linked answer.
I also tried pasting the body (all defs and the lazy val of the AssemblyProject into the body of ForkRun.
To create a jar I ran package at the SBT prompt and get:
[info] Packaging ./target/scala_2.8.1/dsg_2.8.1-1.0.jar ...
[info] Packaging complete.
So I tried running the dsg_2.8.1-1.0.jar from the shell via:
java -jar dsg_2.8.1-1.0.jar
But I get:
Failed to load Main-Class manifest attribute from
dsg_2.8.1-1.0.jar
Could this be caused by having multiple entry points into my project? I select from a list when I execute run from the SBT prompt. Perhaps I need to specify the default when creating the package?
Here's a writeup I did on one way to make an executable jar with SBT:
http://janxspirit.blogspot.com/2011/01/create-executable-scala-jar-with-sbt.html
sbt-assembly is a sbt plugin to create a standalone jar of Scala sbt project with all of its dependencies.
Refer this post for more details with an example.