Working with content-type quicktime in ffmpeg throwing error `moov not found`

Question

So my program is setup to download a video and stream it into a file. These videos are .mp4 and .mov.

The problem is that .mov files do not work and I think it's just the way I am streaming the file. But I am not sure. Because .mp4 files work without any errors. But when I use .mov files I get an error saying

Powershell Errors: [mov,mp4,m4a,3gp,3g2,mj2 @ 000002707b9cb700] moov atom not found

Which is coming from this powershell script:

ffmpeg -i $Args[0] -vcodec copy -acodec copy -movflags +faststart $Args[1]

The code that calls this script is as follows:

    streamVideos_PROMISES.push(
      axios({
        method: "get",
        url: video.url,
        responseType: "stream"
      })
    );
  }
});
Promise.all(streamVideos_PROMISES)
  .then(function(response) {
    response.map(response_item => {
      let tempFileName = new Date().valueOf();
      let videoType = response_item.headers["content-type"].split("/")[1];
      if (videoType === "quicktime") videoType = "mov"; <---Maybe the issue?
      const file = fs.createWriteStream(
        `./cache/videos/${tempFileName + "."}${videoType}`
      );
      var spawn = require("child_process").spawn,
        child;
      response_item.data.pipe(file);
      child = spawn("powershell.exe", [
        "./scripts/ffmpeg_convert.ps1",
        `./cache/videos/${tempFileName + "."}${videoType}`,
        ` ./cache/converted_videos/${tempFileName + "."}${videoType}`
      ]);
      child.stdout.on("data", function(data) {
        console.log("Powershell Data: " + data);
      });
      child.stderr.on("data", function(data) {
        console.log("Powershell Errors: " + data);
      });
      child.on("exit", function() {
        console.log("Finished converting thumbnails");
        return thumbsupply.generateThumbnail(
          `./cache/converted_videos/${tempFileName + "."}${videoType}`,
          {
            mimetype: response_item.headers["content-type"]
          }
        );
      });
      child.stdin.end(); //end input
    });
  })
  .catch(err => {
    console.log(err);
    res.status(500).json({ Error: "Could not generate thumbnail" });
  });

note The response_item.headers["content-type"].split("/") for .mov is quicktime, so I assumed that I could interchange the extensions...Which is probably wrong.

Edit So I manually typed in the $args as follows:

ffmpeg -i "./cache/videos/1556897345129.mov" -vcodec copy -acodec copy -movflags +faststart "./cache/converted_videos/are_you_kidding_me.mov"

and it works.

Edit 2

child = spawn("powershell.exe", [
    "./scripts/ffmpeg_convert.ps1",
    "./cache/videos/1556897345129.mov", <-- Using the string literal works.
    ` ./cache/converted_videos/${tempFileName + "."}${videoType}`
  ]);

Answer 1

MOV and MP4 use the same internal structure. MP4 is just the name after MOV was standardized by ISO, so no issue in renaming between the two.

You should wait till your video file is completely written before trying to extract anything from it.