Nextflow Language Server

A language server for Nextflow scripts and config files.

The following language features are currently supported:

• code navigation (outline, go to definition, find references)
• completion
• diagnostics (errors, warnings)
• formatting
• hover hints
• rename
• DAG preview for workflows

Requirements

The language server requires Java 17 or later.

Configuration

The language server exposes a set of configuration settings that can be controlled through the workspace/didChangeConfiguration event. See the Nextflow VS Code extension for an example of how to set up these configuration settings with sensible defaults.

Development

To build from the command line:

./gradlew build

To run unit tests:

./gradlew test

To run the language server:

java -jar build/libs/language-server-all.jar

Protocol messages are exchanged using standard input/output.

Troubleshooting

Sometimes the language server might crash or get out of sync with your workspace. If this happens, you can restart the server from the command palette. You can also view the server logs from the "Output" tab under "Nextflow Language Server".

When reporting an issue, please include a minimal code snippet that triggers the issue as well as any error traces from the server logs.

Credits

Based on GroovyLanguageServer/groovy-language-server.