feat: allow to save version's json and jar

src/core/arguments.ts

@@ -73,12 +73,16 @@ function parseArg(
   return this;
 }
 
-function generateClassPaths(versionManifest: Version, librariesRoot: string) {
+function generateClassPaths(
+  versionManifest: Version,
+  librariesRoot: string,
+  versionJar: string,
+) {
   const libs = getLibraries(versionManifest, librariesRoot).map(
     (lib) => lib.path,
   );
 
-  libs.push(path.join(librariesRoot, "..", "versions", `${versionManifest.id}.jar`))
+  libs.push(versionJar);
 
   return libs.join(path.delimiter);
 }
@@ -87,6 +91,7 @@ export async function generateLaunchArguments(
   versionManifest: Version,
   javaRoot: string,
   gameRoot: string,
+  versionJar: string,
   auth: Auth,
   options = {
     minRam: "2G",
@@ -103,6 +108,7 @@ export async function generateLaunchArguments(
   const classPaths = generateClassPaths(
     versionManifest,
     path.join(gameRoot, "libraries"),
+    versionJar,
   );
 
   function p(args: string[], arg: Argument) {
@@ -116,7 +122,7 @@ export async function generateLaunchArguments(
     p(game, arg);
   }
 
-  const log4j = await getArgument(versionManifest, gameRoot)
+  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/version.ts

@@ -1,9 +1,9 @@
 import { downloadFile, fetchJson } from "../utils/fetch";
-import { exists } from "../utils/fs";
+import { exists, readJson } from "../utils/fs";
 import { Versions, Version } from "../utils/types";
 import path from "path";
 
-export async function getVersionManifest(versionString: string) {
+export async function getVersionManifestUrl(versionString: string) {
   const versions = await (
     await fetchJson<Versions>(
       "https://piston-meta.mojang.com/mc/game/version_manifest_v2.json",
@@ -20,20 +20,36 @@ export async function getVersionManifest(versionString: string) {
     }
   }
 
-  const versionManifest = await fetchJson<Version>(versionManifestURL);
-
-  return versionManifest;
+  return versionManifestURL;
 }
 
-export async function downloadJar(versionManifest: Version, gameRoot: string) {
-  const destination = path.join(
-    gameRoot,
-    "versions",
-    `${versionManifest.id}.jar`,
-  );
+export async function downloadJson(versionString: string, to: string) {
+  const destination = path.join(to, `${versionString}.json`);
+  if (!(await exists(destination)))
+    await downloadFile({
+      url: await getVersionManifestUrl(versionString),
+      path: destination,
+    });
+}
+
+export async function downloadJar(versionManifest: Version, to: string) {
+  const destination = path.join(to, `${versionManifest.id}.jar`);
   if (!(await exists(destination)))
     await downloadFile({
       url: versionManifest.downloads.client.url,
       path: destination,
     });
 }
+
+export async function getVersionManifest(
+  versionString: string,
+  to: string,
+): Promise<Version> {
+  const destination = path.join(to, `${versionString}.json`);
+  if (await exists(destination)) {
+    return await readJson(destination);
+  }
+
+  await downloadJson(versionString, to);
+  return await readJson(destination);
+}

src/utils/fs.ts

@@ -15,3 +15,7 @@ export async function ensureDir(path: string, recursive = false) {
     return true;
   } else return false;
 }
+
+export async function readJson(destination: string) {
+  return JSON.parse(await fs.readFile(destination, { encoding: "utf-8" }));
+}

tests/assets.test.ts

@@ -4,6 +4,7 @@ import path from "path";
 import fs from "fs/promises";
 
 const assetsPath = path.join(import.meta.dirname, "temp/assets");
+const root = path.join(import.meta.dirname, "temp");
 await fs.rm(assetsPath, { recursive: true, force: true });
 await fs.mkdir(assetsPath, { recursive: true });
 
@@ -23,7 +24,7 @@ test(
   "download assets for 1.21.8 correctly",
   { timeout: 0 },
   async () => {
-    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8");
+    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8", root);
     const assetsDownloader = await nlk.core.AssetsDownloader(assetsPath, versionManifest);
     assetsDownloader.on("completed", () => {
       console.log(

tests/libraries.test.ts

@@ -4,6 +4,7 @@ import path from "path";
 import fs from "fs/promises";
 
 const librariesPath = path.join(import.meta.dirname, "temp/libraries");
+const root = path.join(import.meta.dirname, "temp");
 await fs.rm(librariesPath, { recursive: true, force: true });
 await fs.mkdir(librariesPath, { recursive: true });
 
@@ -23,7 +24,7 @@ test(
   "download libraries for 1.21.8 correctly",
   { timeout: 0 },
   async () => {
-    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8");
+    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8", root);
     const librariesDownloader = await nlk.core.LibrariesDownloader(librariesPath, versionManifest);
     librariesDownloader.on("completed", () => {
       console.log(

tests/log4j.test.ts

@@ -19,7 +19,7 @@ test(
   "download xml file and return correct arguments",
   { timeout: 0 },
   async () => {
-    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8");
+    const versionManifest = await nlk.core.version.getVersionManifest("1.21.8", root);
     const arg = await nlk.core.log4j.getArgument(versionManifest, root);
 
     expect(arg, "correct arg returned").toBe(

tests/natives.test.ts

@@ -4,6 +4,7 @@ import path from "path";
 import fs from "fs/promises";
 
 const nativesPath = path.join(import.meta.dirname, "temp/natives");
+const root = path.join(import.meta.dirname, "temp");
 await fs.rm(nativesPath, { recursive: true, force: true });
 await fs.mkdir(nativesPath, { recursive: true });
 
@@ -21,7 +22,7 @@ vi.stubGlobal("process", { platform: "linux" });
 
 // old version because newer versions doesn't have natives
 test("download natives for 1.15 correctly", { timeout: 0 }, async () => {
-  const versionManifest = await nlk.core.version.getVersionManifest("1.15");
+  const versionManifest = await nlk.core.version.getVersionManifest("1.15", root);
   const nativesDownloader = await nlk.core.NativesDownloader(
     nativesPath,
     versionManifest,

tests/version.test.ts

@@ -3,9 +3,13 @@ import * as nlk from "../dist/index.js";
 import path from "path";
 import fs from "fs/promises";
 
-const versionsPath = path.join(import.meta.dirname, "temp/versions");
-await fs.rm(versionsPath, { recursive: true });
-await fs.mkdir(versionsPath, { recursive: true });
+const root = path.join(import.meta.dirname, "temp");
+try {
+  await fs.rm(path.join(root, "1.21.8.json"));
+  await fs.rm(path.join(root, "1.21.8.jar"));
+} catch (e) {
+  console.warn(e)
+}
 
 async function exists(path: string) {
   try {
@@ -20,14 +24,18 @@ async function exists(path: string) {
 vi.stubGlobal("process", { platform: "linux" });
 
 test("parse arguments correctly for 1.21.8", { timeout: 0 }, async () => {
-  const versionManifest = await nlk.core.version.getVersionManifest("1.21.8");
-  await nlk.core.version.downloadJar(
-    versionManifest,
-    path.join(versionsPath, ".."),
+  const versionManifest = await nlk.core.version.getVersionManifest(
+    "1.21.8",
+    root,
   );
+  await nlk.core.version.downloadJar(versionManifest, root);
 
   expect(
-    await exists(path.join(versionsPath, `${versionManifest.id}.jar`)),
+    await exists(path.join(root, `${versionManifest.id}.jar`)),
     "check jar file",
   ).toBe(true);
+  expect(
+    await exists(path.join(root, `${versionManifest.id}.json`)),
+    "check json file",
+  ).toBe(true);
 });