Fix Alpine Linux binary server (#1016)

Author: cirolosapio

Diff for: package.json

@@ -26,6 +26,7 @@
   },
   "binaryServerDownloadUrl": {
     "linux": "https://github.com/redhat-developer/vscode-xml/releases/download/latest/lemminx-linux.zip",
+    "alpine": "https://github.com/redhat-developer/vscode-xml/releases/download/latest/lemminx-alpine.zip",
     "osx-x86_64": "https://github.com/redhat-developer/vscode-xml/releases/download/latest/lemminx-osx-x86_64.zip",
     "osx-aarch_64": "https://github.com/redhat-developer/vscode-xml/releases/download/latest/lemminx-osx-aarch_64.zip",
     "win32": "https://github.com/redhat-developer/vscode-xml/releases/download/latest/lemminx-win32.zip"

Diff for: src/server/binary/binaryServerStarter.ts

@@ -206,13 +206,24 @@ function getBinaryEnvironment(): any {
   return process.env;
 }
 
+/**
+ * Returns the platform of the current operating system.
+ * If the OS is Alpine Linux, it returns 'alpine'.
+ * Otherwise, it returns the platform string provided by the 'os' module.
+ *
+ * @returns The platform of the current operating system.
+ */
+function getPlatform (): NodeJS.Platform | 'alpine' {
+  return fs.existsSync('/etc/alpine-release') ? 'alpine' : os.platform();
+}
+
 /**
  * Returns the name of the server binary file for the current OS and architecture
  *
  * @return the name of the server binary file for the current OS and architecture
  */
 function getServerBinaryNameWithoutExtension(): string {
-  switch (os.platform()) {
+  switch (getPlatform()) {
     case 'darwin':
       switch (os.arch()) {
         case 'arm64':
@@ -221,7 +232,7 @@ function getServerBinaryNameWithoutExtension(): string {
           return 'lemminx-osx-x86_64';
       }
     default:
-      return `lemminx-${os.platform}`;
+      return `lemminx-${getPlatform()}`;
   }
 }