Scalariform is a great tool for formatting scala code, but the JVM warmup makes it too slow for a CLI application.
By using a client/server architecture, we can fix it.
time java -jar ~/bin/scalariform.jar src/main/scala/Scalariver.scala
3.09s user 0.08s system 129% cpu 2.456 totalScalariform CLI = 3.09 seconds
time ./scalariver src/main/scala/Scalariver.scala
0.07s user 0.03s system 84% cpu 0.153 totalScalariver CLI = 0.07 seconds
Scalariver is 44 times faster than scalariform \o/ Bye bye, JVM warmup.
Get the client, make it executable and run it on some scala file.
wget https://raw.github.com/ornicar/scalariver/master/scalariver
chmod +x scalariver
./scalariver src/main/scala/Scalariver.scalaBy default, this scalariver script takes a file argument,
sends an HTTP request to the server at http://river.scalex.org,
then writes the formatted code to the file.
The client script supports standard scalariform options.
For example, this line will use some formatting preferences, read from stdin and write to stdout even if the source cannot be parsed correctly:
echo src/main/scala/Scalariver.scala | ./scalariver +rewriteArrowSymbols --indentSpaces=4 --stdin --stdout -fEverybody can use http://river.scalex.org API freely.
By default, the scalariver CLI client uses it.
But if you need to format offline, or if you feel uncomfortable about having your code sent to the Internet, then you should run your own scalariver instance.
wget http://download.river.scalex.org/scalariver-1.0.jar
java -jar scalariver-1.0.jarDone!
You can now specify the new server url to the client:
./scalariver --url=http://localhost:8098 src/main/scala/Scalariver.scalaTo make the url change permanent for the scalariver client, add this to your .bashrc/.zshrc:
export SCALARIVER_URL=http://localhost:8098java -jar scalariver-1.0.jar 12345 # listen to port 12345Scalariver now listens to port 12345
To modify or contribute to scalariver, clone this repository and launch sbt. sbt run 12345 will start scalariver on port 12345.
Simplest integration:
au BufEnter *.scala setl formatprg=/path/to/scalariver\ --stdin\ --stdout\ -fExemple with custom server URL and formatting preferences:
au BufEnter *.scala setl formatprg=/path/to/scalariver\ --url=http://localhost\:8098\ --stdin\ --stdout\ -f\ +rewriteArrowSymbols\ +alignSingleLineCaseStatements\ +compactControlReadability\ +doubleIndentConstructorArguments\ +rewriteArrowSymbolsBonus:
" Format the whole file by pressing <leader>f
" This sets a marker on y, goes to the top, formats to the bottom, and returns to the y marker
nmap <leader>f mygggqG'yCheck the scalariver sublime text plugin created by dohzya
Do you use your favorite text editor? Wanna integrate scalariver? Cool.
You need to find a way to send the content of the current file to an external program, then replace the file content with that program output. Sounds easy, right? Please share your work!
Another way to run scalariform without the JVM warmup is to integrate it with SBT.
See these project skeletons for playframework 2.1.5 or playframework 2.2.1.
The server also exposes its functionality through a web form: http://river.scalex.org
The only entry point is a POST request on /.
curl river.scalex.org -d source="class A ( n :Int )"It accepts the following optional parameters:
| name | description | default |
|---|---|---|
| source | scala source code to format | "" |
| scalaVersion | scala version of the source code | 2.10 |
| initialIndentLevel | indent level to add to every line | 0 |
| forceOutput | print the source unchanged if it cannot be parsed correctly | false |
And all scalariform formatting preference options.
More complex example:
curl river.scalex.org \
--data-urlencode source@src/main/scala/Scalariver.scala \
-d scalaVersion=2.11 \
-d rewriteArrowSymbols=true \
-d indentSpaces=4- scalariform - best scala formatter in the wild
- tiscaf - a minimalist and dependency-less HTTP server for scala
It would be nice to have scalariver integration for SBT and your favorite code editor.