feat: add Generate Systemd Unit operation and tests

src/core/config/Categories.json

@@ -329,6 +329,7 @@
             "Find / Replace",
             "Regular expression",
             "Fuzzy Match",
+            "Generate Systemd Unit",
             "Offset checker",
             "Hamming Distance",
             "Levenshtein Distance",

src/core/operations/GenerateSystemdUnit.mjs

@@ -0,0 +1,126 @@
+/**
+ * @author 0xff1ce [github.com/0xff1ce]
+ * @copyright Crown Copyright 2026
+ * @license Apache-2.0
+ */
+
+import Operation from "../Operation.mjs";
+
+const RESTART_OPTIONS = ["no", "on-sucess", "on-failure", "on-abnormal", "on-watchdog", "on-abort", "always"];
+const TYPE_OPTIONS = ["simple", "exec", "forking", "oneshot", "dbus", "notify", "idle"];
+
+/**
+ * GenerateSystemdUnit operation
+ */
+class GenerateSystemdUnit extends Operation {
+
+    /**
+     * GenerateSystemdUnit constructor
+     */
+    constructor() {
+        super();
+
+        this.name = "Generate Systemd Unit";
+        this.module = "Default";
+        this.description = "Generates a systemd unit file based on provided inputs";
+        this.inputType = "string";
+        this.outputType = "string";
+        this.args = [
+            {
+                "name": "Description",
+                "type": "string",
+                "value": "",
+            },
+            {
+                "name": "After",
+                "type": "string",
+                "value": "network.target",
+            },
+            {
+                "name": "Wants",
+                "type": "string",
+                "value": "network-online.target",
+            },
+            {
+                "name": "Restart",
+                "type": "option",
+                "value": RESTART_OPTIONS,
+            },
+            {
+                "name": "Type",
+                "type": "option",
+                "value": TYPE_OPTIONS,
+            },
+            {
+                "name": "ExecStart",
+                "type": "string",
+                "value": "",
+            },
+            {
+                "name": "Environment",
+                "type": "string",
+                "value": "KEY=VALUE",
+            },
+            {
+                "name": "User",
+                "type": "string",
+                "value": "",
+            },
+            {
+                "name": "WorkingDirectory",
+                "type": "string",
+                "value": "",
+            },
+            {
+                "name": "WantedBy",
+                "type": "string",
+                "value": "multi-user.target",
+            },
+        ];
+    }
+
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(_, args) {
+        const description = args[0];
+        const after = args[1];
+        const wants = args[2];
+        const restart = args[3];
+        const type = args[4];
+        const execStart = args[5];
+        const environment = args[6];
+        const user = args[7];
+        const workingDirectory = args[8];
+        const wantedBy = args[9];
+
+        const lines = [];
+
+        // [Unit] section
+        lines.push("[Unit]");
+        if (description) lines.push(`Description=${description}`);
+        if (after) lines.push(`After=${after}`);
+        if (wants) lines.push(`Wants=${wants}`);
+
+        // [Service] section
+        lines.push("");
+        lines.push("[Service]");
+        if (restart) lines.push(`Restart=${restart}`);
+        if (type) lines.push(`Type=${type}`);
+        if (execStart) lines.push(`ExecStart=${execStart}`);
+        if (environment) lines.push(`Environment=${environment}`);
+        if (user) lines.push(`User=${user}`);
+        if (workingDirectory) lines.push(`WorkingDirectory=${workingDirectory}`);
+
+        // [Install] section
+        lines.push("");
+        lines.push("[Install]");
+        if (wantedBy) lines.push(`WantedBy=${wantedBy}`);
+
+        return lines.join("\n");
+    }
+}
+
+export default GenerateSystemdUnit;

tests/operations/index.mjs

@@ -80,6 +80,7 @@ import "./tests/GenerateAllChecksums.mjs";
 import "./tests/GenerateAllHashes.mjs";
 import "./tests/GenerateDeBruijnSequence.mjs";
 import "./tests/GenerateQRCode.mjs";
+import "./tests/GenerateSystemdUnit.mjs";
 import "./tests/GetAllCasings.mjs";
 import "./tests/GOST.mjs";
 import "./tests/Gunzip.mjs";

tests/operations/tests/GenerateSystemdUnit.mjs

@@ -0,0 +1,100 @@
+/**
+ * GenerateSystemdUnit tests.
+ *
+ * @author 0xff1ce
+ * @copyright Crown Copyright 2026
+ * @license Apache-2.0
+ */
+
+import TestRegister from "../../lib/TestRegister.mjs";
+
+TestRegister.addTests([
+    {
+        name: "Generate minimal systemd unit with required defaults",
+        input: "",
+        expectedMatch: /\[Unit\]\nAfter=network\.target\nWants=network-online\.target\n\n\[Service\]\nEnvironment=KEY=VALUE\n\n\[Install\]\nWantedBy=multi-user\.target/,
+        recipeConfig: [
+            {
+                op: "Generate Systemd Unit",
+                args: [
+                    "",                  // Description
+                    "network.target",    // After
+                    "network-online.target", // Wants
+                    "",                  // Restart
+                    "",                  // Type
+                    "",                  // ExecStart
+                    "KEY=VALUE",         // Environment
+                    "",                  // User
+                    "",                  // WorkingDirectory
+                    "multi-user.target"  // WantedBy
+                ]
+            },
+        ],
+    },
+    {
+        name: "Generate full systemd unit with all fields populated",
+        input: "",
+        expectedMatch: /\[Unit\]\nDescription=My Service\nAfter=network\.target\nWants=network-online\.target\n\n\[Service\]\nRestart=always\nType=simple\nExecStart=\/usr\/bin\/node app\.js\nEnvironment=NODE_ENV=production\nUser=www-data\nWorkingDirectory=\/var\/www\n\n\[Install\]\nWantedBy=multi-user\.target/,
+        recipeConfig: [
+            {
+                op: "Generate Systemd Unit",
+                args: [
+                    "My Service",
+                    "network.target",
+                    "network-online.target",
+                    "always",
+                    "simple",
+                    "/usr/bin/node app.js",
+                    "NODE_ENV=production",
+                    "www-data",
+                    "/var/www",
+                    "multi-user.target"
+                ]
+            },
+        ],
+    },
+    {
+        name: "Generate unit without optional Service fields",
+        input: "",
+        expectedMatch: /\[Unit\]\nDescription=Test\nAfter=network\.target\nWants=network-online\.target\n\n\[Service\]\nEnvironment=KEY=VALUE\n\n\[Install\]\nWantedBy=multi-user\.target/,
+        recipeConfig: [
+            {
+                op: "Generate Systemd Unit",
+                args: [
+                    "Test",
+                    "network.target",
+                    "network-online.target",
+                    "",     // Restart
+                    "",     // Type
+                    "",     // ExecStart
+                    "KEY=VALUE",
+                    "",     // User
+                    "",     // WorkingDirectory
+                    "multi-user.target"
+                ]
+            },
+        ],
+    },
+    {
+        name: "Generate unit with custom dependencies and install target",
+        input: "",
+        expectedMatch: /\[Unit\]\nDescription=Custom\nAfter=docker\.service\nWants=network\.target\n\n\[Service\]\nRestart=on-failure\nType=exec\nExecStart=\/bin\/bash start\.sh\nEnvironment=ENV=dev\n\n\[Install\]\nWantedBy=graphical\.target/,
+        recipeConfig: [
+            {
+                op: "Generate Systemd Unit",
+                args: [
+                    "Custom",
+                    "docker.service",
+                    "network.target",
+                    "on-failure",
+                    "exec",
+                    "/bin/bash start.sh",
+                    "ENV=dev",
+                    "",     // User
+                    "",     // WorkingDirectory
+                    "graphical.target"
+                ]
+            },
+        ],
+    }
+]);