Improve getting the Hostname for _host/Hostname Channel

(cherry picked from commit bdd2d1e)
JonasBuch · May 6, 2021 · 2ab79dd · 2ab79dd
1 parent f700d03
commit 2ab79dd
Showing 1 changed file with 22 additions and 3 deletions.
diff --git a/io.openems.edge.core/src/io/openems/edge/core/host/HostImpl.java b/io.openems.edge.core/src/io/openems/edge/core/host/HostImpl.java
@@ -1,7 +1,9 @@
 package io.openems.edge.core.host;
 
+import java.io.IOException;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
+import java.util.Scanner;
 import java.util.concurrent.CompletableFuture;
 
 import org.osgi.framework.BundleContext;
@@ -75,9 +77,13 @@ public HostImpl() {
 
 		// Initialize 'Hostname' channel
 		try {
-			this._setHostname(InetAddress.getLocalHost().getHostName());
-		} catch (UnknownHostException e) {
-			e.printStackTrace();
+			this._setHostname(HostImpl.execReadToString("hostname"));
+		} catch (IOException e) {
+			try {
+				this._setHostname(InetAddress.getLocalHost().getHostName());
+			} catch (UnknownHostException e1) {
+				e1.printStackTrace();
+			}
 		}
 	}
 
@@ -189,4 +195,17 @@ protected void logWarn(Logger log, String message) {
 	protected void logError(Logger log, String message) {
 		super.logError(log, message);
 	}
+
+	/**
+	 * Source: https://stackoverflow.com/a/28043703.
+	 * 
+	 * @param execCommand the command
+	 * @return the parsed result
+	 * @throws IOException
+	 */
+	private static String execReadToString(String execCommand) throws IOException {
+		try (Scanner s = new Scanner(Runtime.getRuntime().exec(execCommand).getInputStream()).useDelimiter("\\A")) {
+			return s.hasNext() ? s.next().trim() : "";
+		}
+	}
 }