improve machine error when running on Linux

On Linux, Podman Desktop can talk to the Podman socket of the host and
to the ones of the Linux VM.  As outlinted in #42, talking to socket of
the host's Podman is currently not supported by the extension.  While
logging into the container registry is perfectly fine, running
subscriptio-manager is not; it requires root privileges to install and
run it.  So instead of a silent error, throw a user-visible error
indicating that it's currently not supported on a Linux host.

Fixes: #42
Signed-off-by: Valentin Rothberg <[email protected]>

src/extension.ts

@@ -27,6 +27,7 @@ import path from 'node:path';
 import { accessSync, constants, existsSync, readFileSync } from 'node:fs';
 import { restartPodmanMachine, runRpmInstallSubscriptionManager, runSubscriptionManager, runSubscriptionManagerActivationStatus, runSubscriptionManagerRegister } from './podman-cli';
 import { SubscriptionManagerClient } from '@redhat-developer/rhsm-client';
+import { isLinux } from './util';
 
 let loginService: RedHatAuthenticationService;
 let currentSession: extensionApi.AuthenticationSession | undefined;
@@ -156,7 +157,7 @@ async function  createOrReuseActivationKey() {
 
 function isPodmanMachineRunning(): boolean {
   const conns = extensionApi.provider.getContainerConnections();
-  const startedPodman = conns.filter(conn => conn.providerId === 'podman' && conn.connection.status() === 'started');
+  const startedPodman = conns.filter(conn => conn.providerId === 'podman' && conn.connection.status() === 'started' && !conn.connection.endpoint.socketPath.startsWith("/run/user/"));
   return startedPodman.length === 1;
 }
 
@@ -255,7 +256,11 @@ export async function activate(extensionContext: extensionApi.ExtensionContext):
       location: extensionApi.ProgressLocation.TASK_WIDGET, title: 'Activating Red Hat Subscription'
       }, async (progress) => {
         if (!isPodmanMachineRunning()) {
-          await extensionApi.window.showInformationMessage('Podman machine is not running. Please start it and try again.');
+          if (isLinux()) {
+            await extensionApi.window.showInformationMessage('Signing into a Red Hat account requires a running Podman machine, and is currently not supported on a Linux host.  Please start a Podman machine and try again.');
+          } else {
+            await extensionApi.window.showInformationMessage('Signing into a Red Hat account requires a running Podman machine.  Please start one and try again.');
+          }
           return;
         } else {
           if (!(await isSubscriptionManagerInstalled())) {