json subtitles to srt format

.babelrc

@@ -0,0 +1,3 @@
+{
+ "presets": ["@babel/preset-env"]
+}

.eslintrc.cjs

@@ -2,6 +2,7 @@ module.exports = {
  env: {
  es2021: true,
  node: true,
+ jest: true,
  },
  extends: ["eslint:recommended", "prettier"],
  plugins: ["prettier"],

__tests__/utils/utils.test.js

@@ -0,0 +1,20 @@
+import { jsonToSrt } from "../../src/utils/utils.js";
+
+describe("utils", () => {
+ it("conver YandexSubtitles json to srt", () => {
+ const jsonYS = [
+ { text: "Привет", startMs: 2222.0, durationMs: 3610.0 },
+ { text: "мир", startMs: 26050.0, durationMs: 970.0 },
+ ];
+
+ const expectedSRT = `1
+00:00:02,222 --> 00:00:05,832
+Привет
+
+2
+00:00:26,050 --> 00:00:27,020
+мир`;
+
+ expect(jsonToSrt(jsonYS)).toBe(expectedSRT);
+ });
+});

package.json

@@ -10,7 +10,8 @@
  "lint": "npx eslint .",
  "lint-fix": "npx eslint . --fix",
  "format": "prettier --write --ignore-unknown \"src/**/*.{js,ts,json}\"",
- "prepare": "husky"
+ "prepare": "husky",
+ "test": "jest"
  },
  "repository": {
  "type": "git",
@@ -44,10 +45,14 @@
  "uuid": "^10.0.0"
  },
  "devDependencies": {
+ "@babel/core": "^7.24.9",
+ "@babel/preset-env": "^7.24.8",
+ "babel-jest": "^29.7.0",
  "eslint": "^8.56.0",
  "eslint-config-prettier": "^9.1.0",
  "eslint-plugin-prettier": "^5.1.3",
  "husky": "^9.0.11",
+ "jest": "^29.7.0",
  "prettier": "^3.3.2"
  }
 }

src/download.js

@@ -1,5 +1,7 @@
 import fs from "fs";
+import { Writable } from "stream";
 import axios from "axios";
+import { jsonToSrt } from "./utils/utils.js";
 
 function calcPercents(current, max) {
  return ((current / max) * 100).toFixed(1);
@@ -9,7 +11,7 @@ export default async function downloadFile(url, outputPath, subtask, videoId) {
  if (!url) {
  throw new Error("Invalid download link");
  }
-
+ const IS_NEED_CONVERT = outputPath.endsWith(".srt");
  const writer = fs.createWriteStream(outputPath);
  const { data, headers } = await axios({
  method: "get",
@@ -31,7 +33,23 @@ export default async function downloadFile(url, outputPath, subtask, videoId) {
  // console.log(calcPercents(downloadedLength, totalLength))
  });
 
- data.pipe(writer);
+ if (IS_NEED_CONVERT) {
+ let dataBuffer = "";
+ const writableStream = new Writable({
+ write(chunk, encoding, callback) {
+ dataBuffer += chunk.toString();
+ callback();
+ },
+ });
+ data.pipe(writableStream);
+ data.on("end", () => {
+ const jsonData = JSON.parse(dataBuffer);
+ writer.write(jsonToSrt(jsonData["subtitles"]));
+ writer.end();
+ });
+ } else {
+ data.pipe(writer);
+ }
 
  return new Promise((resolve, reject) => {
  writer.on("finish", resolve);

src/index.js

@@ -49,7 +49,9 @@ const argv = parseArgs(process.argv.slice(2));
 const ARG_LINKS = argv._;
 const OUTPUT_DIR = argv.output;
 const OUTPUT_FILE = argv["output-file"];
-const IS_SUBS_REQ = argv.subs || argv.subtitles;
+const IS_SUBS_FORMAT_SRT = argv["subs-srt"] || argv["subtitles-srt"];
+const RESPONSE_SUBTITLES_FORMAT = IS_SUBS_FORMAT_SRT ? "srt" : "json";
+const IS_SUBS_REQ = argv.subs || argv.subtitles || IS_SUBS_FORMAT_SRT;
 const ARG_HELP = argv.help || argv.h;
 const ARG_VERSION = argv.version || argv.v;
 const PROXY_STRING = argv.proxy;
@@ -398,12 +400,12 @@ async function main() {
 
  const taskSubTitle = `(ID: ${videoId})`;
  const filename = OUTPUT_FILE
- ? OUTPUT_FILE.endsWith(".json")
+ ? OUTPUT_FILE.endsWith(`.${RESPONSE_SUBTITLES_FORMAT}`)
  ? OUTPUT_FILE
- : `${OUTPUT_FILE}.json`
+ : `${OUTPUT_FILE}.${RESPONSE_SUBTITLES_FORMAT}`
  : `${subOnReqLang.language}---${clearFileName(
  videoId,
- )}---${uuidv4()}.json`;
+ )}---${uuidv4()}.${RESPONSE_SUBTITLES_FORMAT}`;
  await downloadFile(
  subOnReqLang.url,
  `${OUTPUT_DIR}/${filename}`,

src/utils/utils.js

@@ -2,4 +2,25 @@ function clearFileName(name) {
  return name.replace(/[^\w.-]/g, "");
 }
 
-export { clearFileName };
+function convertToSrtTimeFormat(ms) {
+ const date = new Date(ms);
+ const hours = String(date.getUTCHours()).padStart(2, "0");
+ const minutes = String(date.getUTCMinutes()).padStart(2, "0");
+ const seconds = String(date.getUTCSeconds()).padStart(2, "0");
+ const milliseconds = String(date.getUTCMilliseconds()).padStart(3, "0");
+ return `${hours}:${minutes}:${seconds},${milliseconds}`;
+}
+
+function jsonToSrt(subtitles) {
+ return subtitles
+ .map((s, index) => {
+ const { text, startMs, durationMs } = s;
+ const startTime = convertToSrtTimeFormat(startMs);
+ const endTime = convertToSrtTimeFormat(startMs + durationMs);
+ return `${index + 1}\n${startTime} --> ${endTime}\n${text}\n`;
+ })
+ .join("\n")
+ .trim();
+}
+
+export { clearFileName, jsonToSrt };