feat: add a nodejs binary for transmux via command line (#366)

Author: brandonocasey

bin/transmux.js

@@ -0,0 +1,126 @@
+#!/usr/bin/env node
+/* eslint-disable no-console */
+
+const fs = require('fs');
+const path = require('path');
+const {Transmuxer} = require('../lib/mp4');
+const {version} = require('../package.json');
+const {concatTypedArrays} = require('@videojs/vhs-utils/cjs/byte-helpers');
+const {ONE_SECOND_IN_TS} = require('../lib/utils/clock.js');
+
+const showHelp = function() {
+  console.log(`
+  transmux media-file > foo.mp4
+  transmux media-file -o foo.mp4
+  curl -s 'some-media-ulr' | transmux.js -o foo.mp4
+  wget -O - -o /dev/null 'some-media-url' | transmux.js -o foo.mp4
+
+  transmux a supported segment (ts or adts) info an fmp4
+
+  -h, --help                 print help
+  -v, --version              print the version
+  -o, --output    <string>   write to a file instead of stdout
+  -d, --debugger             add a break point just before data goes to transmuxer
+`);
+};
+
+const parseArgs = function(args) {
+  const options = {};
+
+  for (let i = 0; i < args.length; i++) {
+    const arg = args[i];
+
+    if ((/^--version|-v$/).test(arg)) {
+      console.log(`transmux.js v${version}`);
+      process.exit(0);
+    } else if ((/^--help|-h$/).test(arg)) {
+      showHelp();
+      process.exit(0);
+    } else if ((/^--debugger|-d$/).test(arg)) {
+      options.debugger = true;
+    } else if ((/^--output|-o$/).test(arg)) {
+      i++;
+      options.output = args[i];
+    } else {
+      options.file = arg;
+    }
+  }
+
+  return options;
+};
+
+const cli = function(stdin) {
+  const options = parseArgs(process.argv.slice(2));
+  let inputStream;
+  let outputStream;
+
+  // if stdin was provided
+  if (stdin && options.file) {
+    console.error(`You cannot pass in a file ${options.file} and pipe from stdin!`);
+    process.exit(1);
+  }
+
+  if (stdin) {
+    inputStream = process.stdin;
+  } else if (options.file) {
+    inputStream = fs.createReadStream(path.resolve(options.file));
+  }
+
+  if (!inputStream) {
+    console.error('A file or stdin must be passed in as an argument or via pipeing to this script!');
+    process.exit(1);
+  }
+
+  if (options.output) {
+    outputStream = fs.createWriteStream(path.resolve(options.output), {
+      encoding: null
+    });
+  } else {
+    outputStream = process.stdout;
+  }
+
+  return new Promise(function(resolve, reject) {
+    let allData;
+
+    inputStream.on('data', (chunk) => {
+      allData = concatTypedArrays(allData, chunk);
+    });
+    inputStream.on('error', reject);
+
+    inputStream.on('close', () => {
+      if (!allData || !allData.length) {
+        return reject('file is empty');
+      }
+      resolve(allData);
+    });
+  }).then(function(inputData) {
+    const transmuxer = new Transmuxer();
+
+    // Setting the BMDT to ensure that captions and id3 tags are not
+    // time-shifted by this value when they are output and instead are
+    // zero-based
+    transmuxer.setBaseMediaDecodeTime(ONE_SECOND_IN_TS);
+
+    transmuxer.on('data', function(data) {
+      if (data.initSegment) {
+        outputStream.write(concatTypedArrays(data.initSegment, data.data));
+      } else {
+        outputStream.write(data.data);
+      }
+    });
+
+    if (options.debugger) {
+      // eslint-disable-next-line
+      debugger;
+    }
+    transmuxer.push(inputData);
+    transmuxer.flush();
+    process.exit(0);
+  }).catch(function(e) {
+    console.error(e);
+    process.exit(1);
+  });
+};
+
+// no stdin if isTTY is set
+cli(!process.stdin.isTTY ? process.stdin : null);

package-lock.json

@@ -9,6 +9,9 @@
   "main": "./cjs/index.js",
   "module": "es/index.js",
   "browser": "dist/mux.js",
+  "bin": {
+    "muxjs-transmux": "bin/transmux.js"
+  },
   "generator-videojs-plugin": {
     "version": "7.7.3"
   },
@@ -70,6 +73,7 @@
     ]
   },
   "files": [
+    "bin/",
     "CONTRIBUTING.md",
     "cjs/",
     "dist/",
@@ -97,6 +101,7 @@
     "@babel/cli": "^7.11.6",
     "@videojs/babel-config": "^0.2.0",
     "@videojs/generator-helpers": "~2.0.1",
+    "@videojs/vhs-utils": "^3.0.0",
     "global": "^4.4.0",
     "karma": "^5.0.0",
     "rollup": "^2.37.1",