Skip to content

Instantly share code, notes, and snippets.

@buzzdev

buzzdev/app.js

Forked from satori99/app.js
Last active April 9, 2021 10:24
Show Gist options
  • Save buzzdev/0c0b81e93280e66c42926aff7559a117 to your computer and use it in GitHub Desktop.
Save buzzdev/0c0b81e93280e66c42926aff7559a117 to your computer and use it in GitHub Desktop.
Download ZIP

Revisions

  1. @satori99 satori99 revised this gist Aug 10, 2019. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -30,8 +30,8 @@ const crypto = require( 'crypto' );
    const { spawn } = require( 'child_process' );
    const { Transform } = require( 'stream' );

    // https://www.scte.org/SCTEDocs/Standards/SCTE%2035%202017.pdf
    // Section 9.2, page 23
    // https://www.scte.org/SCTEDocs/Standards/ANSI_SCTE%2035%202019r1.pdf
    // Section 9.6, page 29
    class SpliceInfoSection {

    static validate ( buffer ) {
  2. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -298,7 +298,7 @@ const app = ( req, res ) => {
    scte35Stream.on( 'data', info => {
    console.log( 'scte35 info:', info );
    // set volume of stream
    ffmpeg.stdin.write( `Cvolume -1 volume ${info.out_of_network_indicator?0.25:1.0}\n` );
    ffmpeg.stdin.write( `Cvolume ${info.pts_adjustment} volume ${info.out_of_network_indicator?0.25:1.0}\n` );
    } );
    ffmpeg.stdout.pipe( scte35Stream );

  3. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 2 additions and 0 deletions.
    2 changes: 2 additions & 0 deletions app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -237,6 +237,8 @@ const createProcess = ( input, output ) => new Promise( ( resolve, reject ) => {
    '-hide_banner',
    '-loglevel', 'warning',
    '-threads', '2',
    '-analyzeduration', '5MB',
    '-probesize', '5MB',
    // video frames are not decoded
    '-map', '0:v', '-vcodec', 'copy', '-vsync', '0',
    // audio frames are decoded to alter the volume
  4. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -47,7 +47,7 @@ class SpliceInfoSection {

    static from ( buffer ) {
    if ( ! SpliceInfoSection.validate( buffer ) )
    throw new ValueError( 'invalid splice info section: CRC error' );
    throw new Error( 'invalid splice info section: CRC error' );
    let offset = 0;
    const result = Object.create( SpliceInfoSection.prototype, {
    table_id: {
  5. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 4 additions and 0 deletions.
    4 changes: 4 additions & 0 deletions app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -237,15 +237,19 @@ const createProcess = ( input, output ) => new Promise( ( resolve, reject ) => {
    '-hide_banner',
    '-loglevel', 'warning',
    '-threads', '2',
    // video frames are not decoded
    '-map', '0:v', '-vcodec', 'copy', '-vsync', '0',
    // audio frames are decoded to alter the volume
    '-map', '0:a', '-filter:a', 'volume=1.0',
    '-acodec', 'aac', '-ab', '128k', '-ac', '2', '-async', '1',
    // send video and audio frames to unix domain socket
    // '-f', 'mpegts',
    '-f', 'mp4',
    '-movflags', 'faststart',
    '-movflags', 'empty_moov',
    '-movflags', 'frag_keyframe',
    '-listen', '1', output,
    // send scte 35 data packets to stdout
    '-map', '0:2', '-dcodec', 'copy',
    '-f', 'data', 'pipe:1'
    ] );
  6. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 2 additions and 0 deletions.
    2 changes: 2 additions & 0 deletions app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -16,6 +16,8 @@
    * The volume will be reduced at the start of each ad-break, and restored when
    * the break ends.
    *
    * NB: if using windows, run this in a WSL bash prompt because cmd.exe|powershell
    * doesn't support unix domain sockets.
    */

    // Channel 9 Sydney - 720p HLS stream
  7. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 2 additions and 1 deletion.
    3 changes: 2 additions & 1 deletion app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -28,7 +28,8 @@ const crypto = require( 'crypto' );
    const { spawn } = require( 'child_process' );
    const { Transform } = require( 'stream' );


    // https://www.scte.org/SCTEDocs/Standards/SCTE%2035%202017.pdf
    // Section 9.2, page 23
    class SpliceInfoSection {

    static validate ( buffer ) {
  8. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -236,7 +236,7 @@ const createProcess = ( input, output ) => new Promise( ( resolve, reject ) => {
    '-threads', '2',
    '-map', '0:v', '-vcodec', 'copy', '-vsync', '0',
    '-map', '0:a', '-filter:a', 'volume=1.0',
    '-acodec', 'libfdk_aac', '-ab', '128k', '-ac', '2', '-async', '1',
    '-acodec', 'aac', '-ab', '128k', '-ac', '2', '-async', '1',
    // '-f', 'mpegts',
    '-f', 'mp4',
    '-movflags', 'faststart',
  9. @satori99 satori99 revised this gist Feb 26, 2019. 1 changed file with 3 additions and 84 deletions.
    87 changes: 3 additions & 84 deletions app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -18,9 +18,7 @@
    *
    */

    /*
    * Channel 9 Sydney - 720p HLS stream
    */
    // Channel 9 Sydney - 720p HLS stream
    const SOURCE_URL = 'https://9now-live.akamaized.net/hls/live/708951-b/ch9-syd/master1.m3u8'


    @@ -45,240 +43,166 @@ class SpliceInfoSection {
    }

    static from ( buffer ) {

    if ( ! SpliceInfoSection.validate( buffer ) )
    throw new ValueError( 'invalid splice info section: CRC error' );

    let offset = 0;

    const result = Object.create( SpliceInfoSection.prototype, {

    table_id: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    section_syntax_indicator: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: false
    },

    private_indicator: {
    value: ( buffer[ offset ] & 0x40 ) === 0x40,
    enumerable: false
    },

    section_length: {
    value: ( ( buffer[ offset ++ ] & 0x0f ) << 8 ) | buffer[ offset ++ ],
    enumerable: false
    },

    protocol_version: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    encrypted_packet: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: true
    },

    encryption_algorithm: {
    value: ( buffer[ offset ] & 0x7e ) >> 1,
    enumerable: false
    },

    pts_adjustment: {
    value: ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000,
    enumerable: true
    },

    cw_index: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    tier: {
    value: ( buffer[ offset ++ ] << 4 ) | ( ( buffer[ offset ] & 0xf0 ) >> 4 ),
    enumerable: false
    },

    splice_command_length: {
    value: ( ( buffer[ offset ++ ] & 0x0f ) << 8 ) | buffer[ offset ++ ],
    enumerable: false
    },

    splice_command_type: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    } );

    if ( result.table_id !== 0xfc )
    throw new Error( 'invalid splice Info Section: bad table id' );

    if ( result.section_length !== buffer.length - 3 )
    throw new Error( 'invalid splice Info Section: bad section length' );

    // parse <splice_command_length> byte command

    if ( result.splice_command_type == 0x05 ) {

    Object.defineProperties( result, {

    splice_event_id: {
    enumerable: true,
    value: buffer.slice( offset, offset += 4 ).readInt32BE( 0 )
    },

    splice_event_cancel_indicator: {
    enumerable: true,
    value: ( buffer[ offset ++ ] & 0x80 ) === 0x80
    },

    } );

    if ( ! result.splice_event_cancel_indicator ) {

    Object.defineProperties( result, {

    out_of_network_indicator: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: true
    },

    program_splice_flag: {
    value: ( buffer[ offset ] & 0x40 ) === 0x40,
    enumerable: false
    },

    duration_flag: {
    value: ( buffer[ offset ] & 0x20 ) === 0x20,
    enumerable: false
    },

    splice_immediate_flag: {
    value: ( buffer[ offset ++ ] & 0x10 ) === 0x10,
    enumerable: false
    },

    } );

    }

    if ( result.program_splice_flag && ! result.splice_immediate_flag ) {

    const timeSpecified = ( buffer[ offset ] & 0x80 ) === 0x80;

    Object.defineProperty( result, 'splice_time', {
    value: timeSpecified
    ? ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000
    : -1,
    enumerable: true,
    } );

    }

    if ( ! result.program_splice_flag ) {

    const components = [];

    const componentCount = buffer[ offset ++ ];

    for ( let i = 0 ; i < componentCount; i ++ ) {

    const component = { tag: buffer[ offset ++ ] };

    const timeSpecified = ( buffer[ offset ] & 0x80 ) === 0x80;

    Object.defineProperty( component, 'splice_time', {
    value: timeSpecified
    ? ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000
    : -1,
    enumerable: true,
    } );

    }

    Object.defineProperty( result, 'components', {
    value: Object.freeze( components ),
    enumerable: true
    } )

    } );
    }

    if ( result.duration_flag ) {

    Object.defineProperties( result, {

    auto_return: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: true,
    },

    duration: {
    value: ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000,
    enumerable: true
    },

    } );

    }

    Object.defineProperties( result, {

    unique_program_id: {
    value: ( buffer[ offset ++ ] << 8 ) | buffer[ offset ++ ],
    enumerable: true
    },

    avail_num: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    avails_expected: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    } );

    } else {

    console.error( 'Not a splice_insert command!' );

    }

    // parse descriptors

    const descriptor_loop_length = ( buffer[ offset ++ ] << 8 ) | buffer[ offset ++ ];

    for ( let i = 0; i < descriptor_loop_length; i ++ ) {

    const splice_descriptor = {
    splice_descriptor_tag: buffer[ offset ++ ],
    descriptor_length: buffer[ offset ++ ],
    identifier: buffer.slice( offset, offset += 4 ).readInt32BE( 0 ),
    private_bytes: []
    };

    for ( let j = 0 ; j < splice_descriptor.descriptor_length; j ++ ) {
    for ( let j = 0 ; j < splice_descriptor.descriptor_length; j ++ )
    splice_descriptor.private_bytes.push( buffer[ offset ++ ] );
    }

    }

    //

    Object.defineProperty( result, 'crc', {
    value: buffer.slice( offset, offset += 4 ).readInt32BE( 0 ),
    enumerable: false
    } )

    return result;

    }

    }
    @@ -287,9 +211,7 @@ class SpliceInfoSection {
    class SpliceInfoStream extends Transform {

    constructor ( options ) {

    super( Object.assign( options || {}, { objectMode: true } ) )

    }

    _transform ( buffer, encoding, cb ) {
    @@ -298,7 +220,6 @@ class SpliceInfoStream extends Transform {
    } catch ( err ) {
    console.error( 'SCTE35Stream:', err );
    this.emit( 'invalid', buffer );

    }
    cb();
    }
    @@ -402,9 +323,7 @@ const app = ( req, res ) => {


    const server = http.createServer( app ).listen( 3000, '0.0.0.0', () => {

    console.log( 'Listening...' );

    } );


  10. @satori99 satori99 created this gist Feb 26, 2019.
    411 changes: 411 additions & 0 deletions app.js
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,411 @@
    /**
    * This is a proof-of-concept for using ffmpeg as a HTTP video stream proxy
    * that can reduce ad volume.
    *
    * It only works on streams containing SCTE35 data packets.
    * You can check a stream using:
    *
    * ffmpeg -hide_banner -i <SOURCE_URL> 2>&1 | grep scte_35
    *
    * Start the demo:
    *
    * node app.js
    *
    * Then open http://localhost:3000 in chrome or whatever...
    *
    * The volume will be reduced at the start of each ad-break, and restored when
    * the break ends.
    *
    */

    /*
    * Channel 9 Sydney - 720p HLS stream
    */
    const SOURCE_URL = 'https://9now-live.akamaized.net/hls/live/708951-b/ch9-syd/master1.m3u8'


    const net = require( 'net' );
    const http = require( 'http' );
    const crypto = require( 'crypto' );
    const { spawn } = require( 'child_process' );
    const { Transform } = require( 'stream' );


    class SpliceInfoSection {

    static validate ( buffer ) {
    let crc = 0xffffffff, i = 0;
    const l = buffer.length;
    for ( ; i < l; i ++ ) {
    crc ^= ( ( buffer[ i ] << 24 ) >>> 0 );
    for ( let k = 0; k < 8; k ++ )
    crc = crc & 0x80000000 ? ( crc << 1 ) ^ 0x04c11db7 : crc << 1;
    }
    return crc === 0;
    }

    static from ( buffer ) {

    if ( ! SpliceInfoSection.validate( buffer ) )
    throw new ValueError( 'invalid splice info section: CRC error' );

    let offset = 0;

    const result = Object.create( SpliceInfoSection.prototype, {

    table_id: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    section_syntax_indicator: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: false
    },

    private_indicator: {
    value: ( buffer[ offset ] & 0x40 ) === 0x40,
    enumerable: false
    },

    section_length: {
    value: ( ( buffer[ offset ++ ] & 0x0f ) << 8 ) | buffer[ offset ++ ],
    enumerable: false
    },

    protocol_version: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    encrypted_packet: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: true
    },

    encryption_algorithm: {
    value: ( buffer[ offset ] & 0x7e ) >> 1,
    enumerable: false
    },

    pts_adjustment: {
    value: ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000,
    enumerable: true
    },

    cw_index: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    tier: {
    value: ( buffer[ offset ++ ] << 4 ) | ( ( buffer[ offset ] & 0xf0 ) >> 4 ),
    enumerable: false
    },

    splice_command_length: {
    value: ( ( buffer[ offset ++ ] & 0x0f ) << 8 ) | buffer[ offset ++ ],
    enumerable: false
    },

    splice_command_type: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    } );

    if ( result.table_id !== 0xfc )
    throw new Error( 'invalid splice Info Section: bad table id' );

    if ( result.section_length !== buffer.length - 3 )
    throw new Error( 'invalid splice Info Section: bad section length' );

    // parse <splice_command_length> byte command

    if ( result.splice_command_type == 0x05 ) {

    Object.defineProperties( result, {

    splice_event_id: {
    enumerable: true,
    value: buffer.slice( offset, offset += 4 ).readInt32BE( 0 )
    },

    splice_event_cancel_indicator: {
    enumerable: true,
    value: ( buffer[ offset ++ ] & 0x80 ) === 0x80
    },

    } );

    if ( ! result.splice_event_cancel_indicator ) {

    Object.defineProperties( result, {

    out_of_network_indicator: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: true
    },

    program_splice_flag: {
    value: ( buffer[ offset ] & 0x40 ) === 0x40,
    enumerable: false
    },

    duration_flag: {
    value: ( buffer[ offset ] & 0x20 ) === 0x20,
    enumerable: false
    },

    splice_immediate_flag: {
    value: ( buffer[ offset ++ ] & 0x10 ) === 0x10,
    enumerable: false
    },

    } );

    }

    if ( result.program_splice_flag && ! result.splice_immediate_flag ) {

    const timeSpecified = ( buffer[ offset ] & 0x80 ) === 0x80;

    Object.defineProperty( result, 'splice_time', {
    value: timeSpecified
    ? ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000
    : -1,
    enumerable: true,
    } );

    }

    if ( ! result.program_splice_flag ) {

    const components = [];

    const componentCount = buffer[ offset ++ ];

    for ( let i = 0 ; i < componentCount; i ++ ) {

    const component = { tag: buffer[ offset ++ ] };

    const timeSpecified = ( buffer[ offset ] & 0x80 ) === 0x80;

    Object.defineProperty( component, 'splice_time', {
    value: timeSpecified
    ? ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000
    : -1,
    enumerable: true,
    } );

    }

    Object.defineProperty( result, 'components', {
    value: Object.freeze( components ),
    enumerable: true
    } )

    }

    if ( result.duration_flag ) {

    Object.defineProperties( result, {

    auto_return: {
    value: ( buffer[ offset ] & 0x80 ) === 0x80,
    enumerable: true,
    },

    duration: {
    value: ( ( ( ( buffer[ offset ++ ] & 0x01 ) << 32 ) | buffer.slice( offset, offset += 4 ).readInt32BE( 0 ) ) >>> 0 ) / 90000,
    enumerable: true
    },

    } );

    }

    Object.defineProperties( result, {

    unique_program_id: {
    value: ( buffer[ offset ++ ] << 8 ) | buffer[ offset ++ ],
    enumerable: true
    },

    avail_num: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    avails_expected: {
    value: buffer[ offset ++ ],
    enumerable: false
    },

    } );

    } else {

    console.error( 'Not a splice_insert command!' );

    }

    // parse descriptors

    const descriptor_loop_length = ( buffer[ offset ++ ] << 8 ) | buffer[ offset ++ ];

    for ( let i = 0; i < descriptor_loop_length; i ++ ) {

    const splice_descriptor = {
    splice_descriptor_tag: buffer[ offset ++ ],
    descriptor_length: buffer[ offset ++ ],
    identifier: buffer.slice( offset, offset += 4 ).readInt32BE( 0 ),
    private_bytes: []
    };

    for ( let j = 0 ; j < splice_descriptor.descriptor_length; j ++ ) {
    splice_descriptor.private_bytes.push( buffer[ offset ++ ] );
    }

    }

    //

    Object.defineProperty( result, 'crc', {
    value: buffer.slice( offset, offset += 4 ).readInt32BE( 0 ),
    enumerable: false
    } )

    return result;

    }

    }


    class SpliceInfoStream extends Transform {

    constructor ( options ) {

    super( Object.assign( options || {}, { objectMode: true } ) )

    }

    _transform ( buffer, encoding, cb ) {
    try {
    this.push( SpliceInfoSection.from( buffer ) );
    } catch ( err ) {
    console.error( 'SCTE35Stream:', err );
    this.emit( 'invalid', buffer );

    }
    cb();
    }

    }


    const createProcess = ( input, output ) => new Promise( ( resolve, reject ) => {

    const ffmpeg = spawn( 'ffmpeg', [
    '-i', input,
    '-hide_banner',
    '-loglevel', 'warning',
    '-threads', '2',
    '-map', '0:v', '-vcodec', 'copy', '-vsync', '0',
    '-map', '0:a', '-filter:a', 'volume=1.0',
    '-acodec', 'libfdk_aac', '-ab', '128k', '-ac', '2', '-async', '1',
    // '-f', 'mpegts',
    '-f', 'mp4',
    '-movflags', 'faststart',
    '-movflags', 'empty_moov',
    '-movflags', 'frag_keyframe',
    '-listen', '1', output,
    '-map', '0:2', '-dcodec', 'copy',
    '-f', 'data', 'pipe:1'
    ] );

    ffmpeg.once( 'error', err => {
    console.debug( 'ffmpeg error occurred' );
    clearTimeout( timer );
    reject( new Error( 'Failed to create ffmpeg child process' ) );
    } );

    ffmpeg.once( 'exit', code => {
    console.debug( 'ffmpeg exit has occurred' );
    clearTimeout( timer );
    ffmpeg.removeAllListeners( 'error' );
    ffmpeg.stderr.once( 'data', buffer => {
    reject( buffer.toString( 'utf8' ) );
    } );
    } );

    const timer = setTimeout( () => {
    ffmpeg.removeAllListeners( 'error' );
    ffmpeg.removeAllListeners( 'exit' );
    resolve( ffmpeg );
    }, 150 );

    } );


    const app = ( req, res ) => {

    console.log( 'new request', res.connection.remoteAddress, res.connection.remotePort );

    // create a hash from the remote conn. info to make a unique socket name
    const md5 = crypto.createHash( 'md5' );
    md5.update( res.connection.remoteAddress + res.connection.remotePort );
    const socketPath = `/tmp/adsoft.${md5.digest('hex')}.sock`;

    // create ffmpeg child process
    createProcess( SOURCE_URL, 'unix:' + socketPath ).then( ffmpeg => {
    ffmpeg.once( 'exit', () => console.debug( `ffmpeg child process ${ffmpeg.pid} has exited` ) );
    ffmpeg.stderr.on( 'data', buffer => console.debug( buffer.toString( 'utf8' ) ) );

    const scte35Stream = new SpliceInfoStream();
    scte35Stream.on( 'data', info => {
    console.log( 'scte35 info:', info );
    // set volume of stream
    ffmpeg.stdin.write( `Cvolume -1 volume ${info.out_of_network_indicator?0.25:1.0}\n` );
    } );
    ffmpeg.stdout.pipe( scte35Stream );

    // wait for ffmpeg to create the socket file...
    setTimeout( () => {
    const socket = net.createConnection( socketPath, () => {
    console.debug( 'connected to domain socket' );
    res.setHeader( 'Content-Type', 'video/mp4' );
    socket.pipe( res );
    res.on( 'close', () => {
    console.debug( 'connection closed' )
    socket.destroy();
    } );
    res.on( 'finish', () => {
    console.debug( 'response finished' )
    socket.destroy();
    } );
    } );
    socket.once( 'error', err => {
    console.error( 'unix socket error:', err );
    ffmpeg.kill();
    } );
    }, 500 );

    } ).catch( err => {
    console.error( err );
    res.end( err.toString() );
    } );

    }


    const server = http.createServer( app ).listen( 3000, '0.0.0.0', () => {

    console.log( 'Listening...' );

    } );


    //