Add CLI help option

Author: lfir

.github/dependabot.yml

@@ -0,0 +1,15 @@
+# To get started with Dependabot version updates, you'll need to specify which
+# package ecosystems to update and where the package manifests are located.
+# Please see the documentation for all configuration options:
+# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates
+
+version: 2
+updates:
+  - package-ecosystem: "maven" # See documentation for possible values
+    directory: "/" # Location of package manifests
+    schedule:
+      interval: "daily"
+    ignore:
+      # Ignore all minor and patch updates.
+      - dependency-name: "*"
+        update-types: ["version-update:semver-minor", "version-update:semver-patch"]

README.md

@@ -5,6 +5,27 @@ Fedora 42 systems, using the [KDE Edition](https://fedoraproject.org/kde),
 which comes with Java 21 preinstalled, as a starting point.
 It also sets some configuration options useful for development work and system administration.
 
+Current actions that can be applied (each needs to be confirmed first):
+
+1. Install RPMFusion repositories. 
+Adds free and nonfree RPMFusion repos and imports their GPG keys.
+
+2. Install additional packages with DNF.
+Installs extra packages listed in dnf-install.cf, with the
+option to skip selected packages interactively.
+
+3. Remove unnecessary packages.
+Removes unwanted packages from dnf-remove.cf and performs autoremove.
+
+4. Install Flatpak applications.
+Adds the Flathub remote and installs Flatpaks from flatpak-install.cf.
+
+5. Ensure groups exist and add user.
+Creates and assigns admin-related groups such as _docker_, _libvirt_, and _vboxusers_.
+
+6. Enable and start Cockpit.
+Enables and starts the systemd service of the Cockpit web-based management interface.
+
 ### Run commands
 
 - App
@@ -13,6 +34,8 @@ It also sets some configuration options useful for development work and system a
   java src/main/java/cf/maybelambda/fedora/PostInstallUpdater.java
   ```
 
+`--help` can be passed to see available options.
+
 - Tests
 
   ```

src/main/java/cf/maybelambda/fedora/PostInstallUpdater.java

@@ -23,28 +23,38 @@ public class PostInstallUpdater {
         "https://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-42.noarch.rpm",
         "https://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-42.noarch.rpm"
     );
+
     private static final String flatpakRemoteName = "flathub";
     private static final String flatpakRemoteUrl = "https://dl.flathub.org/repo/flathub.flatpakrepo";
+
     private static final List<String> groupList = List.of(
         "docker", "libvirt", "vboxsf", "vboxusers"
     );
+
+    private static final String CONFIG_DIR = "src/main/resources";
     private static final String DNF_INSTALL_FILE = "dnf-install.cf";
     private static final String DNF_REMOVE_FILE = "dnf-remove.cf";
     private static final String FLATPAK_INSTALL_FILE = "flatpak-install.cf";
+    private static final String HELP_FILE = "help.txt";
 
     private static final String RESET  = "\u001B[0m";
     private static final String YELLOW = "\u001B[33m";
 
     private static boolean dryRun = false;
 
     public static void main(String[] args) {
-        setDryRun(Arrays.asList(args).contains("--dry-run"));
+        if (Arrays.asList(args).contains("-h") || Arrays.asList(args).contains("--help")) {
+            printHelp();
+            return;
+        }
+
         List<String> dnfInstallPackages = loadPackageNamesFrom(DNF_INSTALL_FILE);
         List<String> dnfRemovePackages = loadPackageNamesFrom(DNF_REMOVE_FILE);
         List<String> flatpakInstallPackages = loadPackageNamesFrom(FLATPAK_INSTALL_FILE);
         Scanner scanner = new Scanner(System.in);
 
         System.out.println("Fedora Post Install Actions\n");
+        setDryRun(Arrays.asList(args).contains("--dry-run"));
         if (isDryRun()) {
             System.out.println("---[Dry Run Mode] Shell Commands will not be executed.---\n");
         }
@@ -181,7 +191,7 @@ static int runCommand(String[] command) {
     static List<String> loadPackageNamesFrom(String filename) {
         List<String> packages = new ArrayList<>();
         try {
-            List<String> lines = Files.readAllLines(Path.of("src/main/resources", filename), StandardCharsets.UTF_8);
+            List<String> lines = Files.readAllLines(Path.of(CONFIG_DIR, filename), StandardCharsets.UTF_8);
             for (String line : lines) {
                 String trimmed = line.trim();
                 if (!trimmed.isEmpty() && !trimmed.startsWith("#")) {
@@ -222,4 +232,13 @@ static List<String> promptForExclusions(List<String> packages, Scanner scanner)
 
         return filtered;
     }
+
+    static void printHelp() {
+        try {
+            List<String> lines = Files.readAllLines(Path.of(CONFIG_DIR, HELP_FILE), StandardCharsets.UTF_8);
+            System.out.println(String.join(System.lineSeparator(), lines));
+        } catch (IOException e) {
+            System.err.println("Error reading help file: " + e.getMessage());
+        }
+    }
 }

src/main/resources/help.txt

@@ -0,0 +1,13 @@
+Fedora Post Install Actions
+===========================
+
+Usage:
+  java PostInstallUpdater.java [options]
+
+Options:
+  -h, --help       Show this help page and exit.
+  --dry-run        Print all commands without executing them.
+
+Example:
+  java PostInstallUpdater.java --dry-run
+    Goes through all steps without executing system commands.

src/test/java/cf/maybelambda/fedora/PostInstallUpdaterTests.java

@@ -165,4 +165,17 @@ void runCommandSkipsExecutionInDryRunMode() {
             PostInstallUpdater.setDryRun(false);
         }
     }
+
+    @Test
+    void helpOptionDisplaysHelpTextAndExits() {
+        try (MockedStatic<Files> filesMock = mockStatic(Files.class, CALLS_REAL_METHODS)) {
+            filesMock.when(() -> Files.readAllLines(any(Path.class), eq(StandardCharsets.UTF_8)))
+                .thenReturn(List.of("Usage instructions go here"));
+
+            PostInstallUpdater.main(new String[]{"--help"});
+            PostInstallUpdater.main(new String[]{"-h"});
+
+            filesMock.verify(() -> Files.readAllLines(any(Path.class), eq(StandardCharsets.UTF_8)), Mockito.times(2));
+        }
+    }
 }