ffmpeg 命令永远不会在使用 nodejs 的 lambda 函数中工作

Question

我正在尝试实现 FFmpeg 视频流功能，例如 Instagram 倒计时功能。在这段代码中，首先，我从 s3 存储桶中获取记录（URL），然后根据需要拆分它们，然后创建命令并使用属于 childe_process 的 exec() 执行它。在此，我试图将 out 存储在 lambda 函数中的某个特定文件夹中，但它从未存储过。我认为 lambda 确实允许在本地写入文件，所以我尝试使用 exec() 回调的 stdout 参数在 s3 存储桶上直接上传。伙计们，请帮助做到这一点。我有一个问题 lambda 是否允许在其本地文件夹中写入内容？或者如果不允许那么做那件事的方法是什么？我只是分享我的代码，请指导我。

    // dependencies
var AWS = require('aws-sdk');
var s3 = new AWS.S3();
var { exec } = require('child_process');
var path = require('path')
var AWS_ACCESS_KEY = 'AKIAUIBLAC2U4XQGXPVC';
var AWS_SECRET_ACCESS_KEY = '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';
var fs = require('fs')

s3 = new AWS.S3({
    accessKeyId: AWS_ACCESS_KEY,
    secretAccessKey: AWS_SECRET_ACCESS_KEY
});

exports.handler = async function (event, context) {

    var bucket_name = "sycu-game";
    var bucketName = "sycu-test";

    //CREATE OVERLAY AND BG_VALUE PATH TO GET VALUE FROM S3
    const bgValue = (event.Records[0].bg_value).split('/');
    const overlayImage = (event.Records[0].overlay_image_url).split('/');


    var s3_bg_value = bgValue[3] + "/" + bgValue[4];
    var s3_overlay_image = overlayImage[4] + "/" + overlayImage[5] + "/" + overlayImage[6];
    const signedUrlExpireSeconds = 60 * 5;


    //RETREIVE BG_VALUE FROM S3 AND CREATE URL FOR FFMPEG INPUT VALUE
    var bg_value_url = s3.getSignedUrl('getObject', {
        Bucket: bucket_name,
        Key: s3_bg_value,
        Expires: signedUrlExpireSeconds
    });
    bg_value_url = bg_value_url.split("?");
    bg_value_url = bg_value_url[0];


    //RETREIVE OVERLAY IMAGE FROM S3 AND CREATE URL FOR FFMPEG INPUT VALUE   
    var overlay_image_url = s3.getSignedUrl('getObject', {
        Bucket: bucket_name,
        Key: s3_overlay_image,
        Expires: signedUrlExpireSeconds
    });
    overlay_image_url = overlay_image_url.split("?");
    overlay_image_url = overlay_image_url[0];


    //MANUAL ASSIGN VARIABLE FOR FFMPEG COMMAND 
    var command,
        ExtraTimerSec = event.Records[0].timer_seconds + 5,
        TimerSec = event.Records[0].timer_seconds + 1,
        BackgroundWidth = 1080,
        BackgroundHeight = 1920,
        videoPath = (__dirname + '/tmp/' + event.Records[0].name);
    console.log("path", videoPath)
    //TEMP DIRECTORY

    var videoPath = '/media/volume-d/generatedCountdownS3/tmp/' + event.Records[0].name
    var tmpFile = fs.createWriteStream(videoPath)
    //FFMPEG COMMAND 
    if (event.Records[0].bg_type == 2) {
        if (event.Records[0].is_rotate) {
            command = ' -stream_loop -1 -t ' + ExtraTimerSec + ' -i ' + bg_value_url + ' -i ' + overlay_image_url + ' -filter_complex "color=color=0x000000@0.0:s= ' + event.Records[0].resized_box_width + 'x' + event.Records[0].resized_box_height + ',drawtext=fontcolor=' + event.Records[0].time_text_color + ':fontsize=' + event.Records[0].time_text_size + ':x=' + event.Records[0].minute_x + ':y=' + event.Records[0].minute_y + ':text=\'%{eif\\:trunc(mod(((' + TimerSec + '-if(between(t, 0, 1),1,if(gte(t,' + TimerSec + '),' + TimerSec + ',t)))/60),60))\\:d\\:2}\',drawtext=fontcolor=' + event.Records[0].time_text_color + ':fontsize=' + event.Records[0].time_text_size + ':x=' + event.Records[0].second_x + ':y=' + event.Records[0].second_y + ':text=\'%{eif\\:trunc(mod(' + TimerSec + '-if(between(t, 0, 1),1,if(gte(t,' + TimerSec + '),' + TimerSec + ',t))\,60))\\:d\\:2}\'[txt]; [txt] rotate=' + event.Records[0].box_angle + '*PI/180:fillcolor=#00000000 [rotated];[0] scale=w=' + BackgroundWidth + ':h=' + BackgroundHeight + '[t];[1] scale=w=' + BackgroundWidth + ':h=' + BackgroundHeight + '[ot];[t][ot] overlay = :x=0 :y=0 [m1];[m1][rotated]overlay = :x=' + event.Records[0].flat_box_coordinate_x + ' :y=' + event.Records[0].flat_box_coordinate_x + ' [m2]" -map "[m2]" -pix_fmt yuv420p -t ' +
                ExtraTimerSec + ' -r 24 -c:a copy ' + videoPath + "";
        }
        else {
            command = ' -stream_loop -1 -t ' + ExtraTimerSec + ' -i ' + bg_value_url + ' -i ' + overlay_image_url + ' -filter_complex "color=color=0x000000@0.0:s= ' + event.Records[0].resized_box_width + 'x' + event.Records[0].resized_box_height + ',drawtext=fontcolor=' + event.Records[0].time_text_color + ':fontsize=' + event.Records[0].time_text_size + ':x=' + event.Records[0].minute_x + ':y=' + event.Records[0].minute_y + ':text=\'%{eif\\:trunc(mod(((' + TimerSec + '-if(between(t, 0, 1),1,if(gte(t,' + TimerSec + '),' + TimerSec + ',t)))/60),60))\\:d\\:2}\',drawtext=fontcolor=' + event.Records[0].time_text_color + ':fontsize=' + event.Records[0].time_text_size + ':x=' + event.Records[0].second_x + ':y=' + event.Records[0].second_y + ':text=\'%{eif\\:trunc(mod(' + TimerSec + '-if(between(t, 0, 1),1,if(gte(t,' + TimerSec + '),' + TimerSec + ',t))\,60))\\:d\\:2}\'[txt]; [txt] rotate=' + event.Records[0].box_angle + '*PI/180:fillcolor=#00000000 [rotated];[0] scale=w=' + BackgroundWidth + ':h=' + BackgroundHeight + '[t];[1] scale=w=' + BackgroundWidth + ':h=' + BackgroundHeight + '[ot];[t][ot] overlay = :x=0 :y=0 [m1];[m1][rotated]overlay = :x=' + event.Records[0].flat_box_coordinate_x + ' :y=' + event.Records[0].flat_box_coordinate_x + ' [m2]" -map "[m2]" -pix_fmt yuv420p -t ' +
                ExtraTimerSec + ' -r 24 -c:a copy ' + videoPath + "";
        }
    }
    var final_command = '/usr/bin/ffmpeg' + command;


    //COMMAND EXECUTE HERE

    await exec(final_command, function (err, stdout, stderr) {
        console.log("data is here")
        console.log('err:', err);
        console.log('stdout:', stdout);
        console.log('stderr:', stderr);
        const params = {
            Bucket: bucketName,
            Key: "countdown/output.mp4",
            Body: stdout,
        }
        s3.upload(params).promise().then(data => {
            console.log("data is here -->", data)
        });
    });
    var tmpFile = fs.createReadStream(videoPath)
    console.log('temp file data:', tmpFile.toString())
};

Answer 1

您只能写入 /tmp 文件夹