Question

I’m trying to stream a mp4 file to iOS devices (iPhone and iPad) from a Grails controller:

def streamContent() {
    def contentPath = "/path/to/file"
    File f = new File(contentPath)
    if(f.exists()) {
        response.setContentType("video/mp4")
        response.outputStream << f.newInputStream()
        response.outputStream.flush()
        response.outputStream.close()
    } else {
        render status: 404
    }
}

this code works well on desktop browsers like safari (I see the video), but when I access to the same page with an iPhone or an iPad the video won’t play. Note that if I put the same video on Apache httpd and I request it from iOS devices, there is no problem. So it must be a streaming problem.

On the html page the video is embedded using HTML5 video tag:

<video width="360" height="200" controls>
    <source src="http://localhost:8080/myapp/controller/streamContent" type='video/mp4'>
</video>

Answer 1

I solved this problem by handling Partial Content and Range Requests (HTTP 206 status). It seems that mobile browsers/media players are using partial requests the avoid to much data transfer all at once.
So instead of doing a simple

response.outputStream << f.newInputStream()

I read only the requested bytes when the request is for a range of bytes:

if (isRange) {
    //start and end are requested bytes offsets
    def bytes = new byte[end-start]
    f.newInputStream().read(bytes, start, bytes.length)
    response.outputStream << bytes
    response.status = 206
} else {
    response.outputStream << f.newInputStream()
    response.status = 200
}