How do I get s3-upload to depend on (packageZipTarball in Universal)?

I want to use s3-sbt to upload the result of the package-zip-tarball task (from sbt-native-packager).

Currently, the important part of my build.sbt looks like this:

mappings in upload := Seq(( ((package-zip-tarball in Universal).value) ,"trailhunger2-1.0.tgz"))

host in upload := "trailhunger.s3.amazonaws.com"

credentials += Credentials(Path.userHome / ".s3credentials")

On reload, sbt reports the following:

/Users/sarge/Documents/workspaces/TrailHunger/TrailHunger2/build.sbt:56: error: illegal start of simple expression
mappings in upload := Seq(( ((package-zip-tarball in Universal).value) ,"trailhunger2-1.0.tgz"))
                              ^
/Users/sarge/Documents/workspaces/TrailHunger/TrailHunger2/build.sbt:56: error: ')' expected but eof found.
mappings in upload := Seq(( ((package-zip-tarball in Universal).value) ,"trailhunger2-1.0.tgz"))
                                                                                                ^
[error] Error parsing expression.  Ensure that there are no blank lines within a setting.

Update: After @SethTisue's answer my code now reads:

mappings in upload := Seq( ( (packageZipTarball in Universal).value ,"trailhunger2-1.0.tgz") )

Sadly, I get:

error: not found: value packageZipTarball
mappings in upload := Seq( ( (packageZipTarball in Universal).value ,"trailhunger2-1.0.tgz") )
                              ^
[error] Type error in expression

My expectation is that (packageZipTarball in Universal) does the same thing as universal:packageZipTarball in the console. The .value means that I can get the value of the task which is of type java.io.File. That then gets included in a tuple2 along with the string literal "trailhunger2-1.0.tgz". The surrounding Seq then makes a sequence with precisely one element.

I don't see why the value packageZipTarball cannot be found.

I have verified that show universal:packageZipTarball returns the file name I expect.

Is s3-sbt too old to support the new sbt 0.13 syntax. Is nesting this in Seq incorrect?

Solution

Part 1

Are you using sbt 0.12 or 0.13?

In sbt 0.12 and earlier versions, keys are capitalized-like-this in sbt's interactive mode, but are capitalizedLikeThis in build definitions.

In sbt 0.13 capitalizedLikeThis is accepted in both contexts. (capitalized-like-this is still accepted in interactive mode, but only for backwards compatibility.)

Anyway, regardless of whether you're using 0.12 or 0.13, you need to change package-zip-tarball to packageZipTarball. The Scala parser thinks the former means package - zip - tarball. And package is a keyword, which is where the errors you're getting are coming from.

If you're on 0.13, you can forget the whole hyphens thing entirely as a now-irrelevant historical quirk.

Part 2

I've found that in order for packageZipTarball in Universal to compile, you must add import com.typesafe.sbt.packager.Keys._ to the top of build.sbt.

The sbt-native-packager readme does have a couple uses of import and of explicitly qualified names that begin with com.typesafe.sbt.packager, so there was at least a little indication that something like this might be necessary, but maybe the doc ought to call it out more explicitly.