netbeans.apache.org/src/content/blogs/entry/lsp-client-demo-ba-sh.adoc

// 
//     Licensed to the Apache Software Foundation (ASF) under one
//     or more contributor license agreements.  See the NOTICE file
//     distributed with this work for additional information
//     regarding copyright ownership.  The ASF licenses this file
//     to you under the Apache License, Version 2.0 (the
//     "License"); you may not use this file except in compliance
//     with the License.  You may obtain a copy of the License at
// 
//       http://www.apache.org/licenses/LICENSE-2.0
// 
//     Unless required by applicable law or agreed to in writing,
//     software distributed under the License is distributed on an
//     "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
//     KIND, either express or implied.  See the License for the
//     specific language governing permissions and limitations
//     under the License.
//

= LSP Client demo - (ba)sh language server
:author: Geertjan Wielenga 
:revdate: 2019-08-17
:jbake-type: post
:jbake-tags: blogentry
:jbake-status: published
:keywords: NetBeans at Oracle Code One 2019
:description: NetBeans at Oracle Code One 2019
:toc: left
:toc-title:
:syntax: true



Below is a scenario by Jan Lahoda, the creator of LSP integration for Apache NetBeans, for how to integrate the bash language server with Apache NetBeans, including syntax highlighting.


== Setting Up

. Install npm (and node.js). On Ubuntu, e.g., do "apt install npm", though something different will be needed on Mac OS X.
. Create a directory in which we are going to work, have a terminal opened in that directory.
. Install the bash-language-server:
+
[source,console]
----
    npm install bash-language-server
----
+
On Mac OSX:
+
[source,console]
----
    npm install bash-language-server --unsafe-perm
----
+
This will install the server into the current directory.
. Try the bash server:
+
[source,console]
----
    ./node_modules/bash-language-server/bin/main.js --help
----
+
You should see something like this:
+
[source,console]
----
    Usage:
      bash-language-server start
      bash-language-server -h | --help
      bash-language-server -v | --version
----
. Create a NetBeans module. Create a File Type (Module Development/File Type), mime type: text/sh, file extension: sh

== Syntax Coloring via TextMate

. Download the TextMate grammar file here, and put it alongside the newly created DataObject:
  link:https://raw.githubusercontent.com/microsoft/vscode/master/extensions/shellscript/syntaxes/shell-unix-bash.tmLanguage.json[https://raw.githubusercontent.com/microsoft/vscode/master/extensions/shellscript/syntaxes/shell-unix-bash.tmLanguage.json]
. Add "TextMate Lexer" as a dependency of the module.
. Into the DataObject add this annotation:
+
[source,java]
----
    @GrammarRegistration(grammar="shell-unix-bash.tmLanguage.json", mimeType="text/sh")
----
+
GrammarRegistration is:
+
[source,java]
----
    import org.netbeans.modules.textmate.lexer.api.GrammarRegistration;
----


This should lead to syntax highlighted source for .sh bash files taken from the TextMate grammar file.

== Language Support via the Language Server

Next, we need to add language support using the language server.


. Add "LSP Client" and "MIME Lookup API" as dependencies of the module.

. Create a new class, ShellClient, in the module, put this into it, (replacing " " with the absolute path to "node_modules/bash-language-server"):
+
[source,java]
----
    import java.io.IOException;
    import org.netbeans.api.editor.mimelookup.MimeRegistration;
    import org.netbeans.modules.lsp.client.spi.LanguageServerProvider;
    import org.openide.util.Exceptions;
    import org.openide.util.Lookup;

    @MimeRegistration(mimeType="text/sh", service=LanguageServerProvider.class)
    public class ShellClient implements LanguageServerProvider {

       @Override
       public LanguageServerDescription startServer(Lookup lkp) {
           try {
               Process p = new ProcessBuilder("/bin/main.js", "start").start();
               return LanguageServerDescription.create(p.getInputStream(), p.getOutputStream(), p);
           } catch (IOException ex) {
               Exceptions.printStackTrace(ex);
               return null;
           }
       }

    }
----
+
You may need to explicitly call node in the above code, i.e., as follows:
+
[source,java]
----
    Process p = new ProcessBuilder(
            "/usr/local/bin/node", 
            "/bin/main.js", 
            "start").start();
----
. Build and start the module.



Caveat: the language server is started only for files that are inside a project, so create (any) new project, and inside the project, put a shell file. E.g. copy "bin/netbeans" as "test.sh" into the project. Open it in the editor - there should be syntax highlighting, Navigator, and code completion should show something, etc.