feat: add a function to handle log4j fix and its test, add it to arguments.ts and finish arguments.test.ts

src/core/arguments.ts

@@ -4,6 +4,7 @@ import { Argument, Auth, PoolFile, Version } from "../utils/types";
 import { getJavaExecutable } from "./java";
 import { getLibraries } from "./libraries";
 import { version as packageVersion } from "../../package.json";
+import { getArgument } from "./log4j";
 
 function fillArguments(
   arg: string,
@@ -82,7 +83,7 @@ function generateClassPaths(versionManifest: Version, librariesRoot: string) {
   return libs.join(path.delimiter);
 }
 
-export function generateLaunchArguments(
+export async function generateLaunchArguments(
   versionManifest: Version,
   javaRoot: string,
   gameRoot: string,
@@ -115,5 +116,7 @@ export function generateLaunchArguments(
     p(game, arg);
   }
 
-  return `${getJavaExecutable(javaRoot)} ${jvm.join(" ")}${options.customJvm === "" ? "" : ` ${options.customJvm}`} -Xms${options.minRam} -Xmx${options.maxRam} -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M ${versionManifest.mainClass} ${game.join(" ")}`;
+  const log4j = await getArgument(versionManifest, gameRoot)
+
+  return `${getJavaExecutable(javaRoot)} ${jvm.join(" ")}${options.customJvm === "" ? "" : ` ${options.customJvm}`} -Xms${options.minRam} -Xmx${options.maxRam} -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M ${log4j} ${versionManifest.mainClass} ${game.join(" ")}`;
 }

src/core/index.ts

@@ -3,4 +3,5 @@ export * as version from "./version";
 export * as natives from "./natives";
 export * as libraries from "./libraries";
 export * as assets from "./assets";
-export * as arguments from "./arguments"
+export * as arguments from "./arguments"
+export * as log4j from "./log4j"

src/core/log4j.ts

@@ -0,0 +1,34 @@
+import path from "path";
+import { downloadFile } from "../utils/fetch";
+import { Version } from "../utils/types";
+import { exists } from "../utils/fs";
+import { hash } from "crypto";
+import fs from "fs/promises";
+
+export async function getArgument(
+  versionManifest: Version,
+  destination: string,
+) {
+  const xmlDestination = path.join(
+    destination,
+    versionManifest.logging.client.file.id,
+  );
+  if (!(await exists(xmlDestination))) {
+    await downloadFile({
+      url: versionManifest.logging.client.file.url,
+      path: xmlDestination,
+    });
+
+    if (
+      hash("sha1", await fs.readFile(xmlDestination, {encoding: "utf-8"})) !==
+      versionManifest.logging.client.file.sha1
+    ) {
+      throw new Error("Wrong hash for log4j's xml config");
+    }
+  }
+
+  return versionManifest.logging.client.argument.replace(
+    "${path}",
+    xmlDestination,
+  );
+}

tests/log4j.test.ts

@@ -0,0 +1,34 @@
+import { expect, test, vi } from "vitest";
+import * as nlk from "../dist/index.js";
+import path from "path";
+import { hash } from "crypto";
+import fs from "fs/promises";
+
+const root = path.join(import.meta.dirname, "temp");
+const xmlFile = path.join(root, "client-1.21.2.xml");
+try {
+  await fs.rm(xmlFile, { recursive: true });
+} catch {
+  // first time the test is runned
+}
+
+// mock os to linux for testing
+vi.stubGlobal("process", { platform: "linux" });
+
+test(
+  "download xml file and return correct arguments",
+  { timeout: 10000 },
+  async () => {
+    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8");
+    const arg = await nlk.core.log4j.getArgument(versionManifest, root);
+
+    expect(arg, "correct arg returned").toBe(
+      `-Dlog4j.configurationFile=${xmlFile}`,
+    );
+
+    expect(
+      hash("sha1", await fs.readFile(xmlFile, { encoding: "utf-8" })),
+      "correct hash",
+    ).toBe("39384bd14c0606d812afec88d8aff595b2587dd9");
+  },
+);