Start after stop does not work for "zms mjpeg" on Watch page

[IgorA100]

Is it just me or is something broken?
On the Watch page, select the "ZMS MJPEG" player, refresh the page, click the "Stop" button, and then click the "Play" button
Play does NOT start.
At the same time, "nph-zms" are multiplying and consuming resources.

[connortechnology]

That's not good.
First thing we need to check is if stop is actually stopping the zms process (it should).
Next... is the src= value valid? If they reuse the connKey, there is a lock, and so subsequent zms processes will be waiting on the lock. So we need to make sure the first process dies. Maybe we should just generate a new connKey on play.

[IgorA100]

thing we need to check is if stop is actually stopping the zms process (it should).

If you execute .kill(), the process continues to work actively (consuming resources).
If you remove the line stream.src = ''; in the .kill() method, then zms process remains hanging, but does not consume resources.

src= value valid?

When normal playback is in progress:
http://192.168.111.245:30020/zm/cgi-bin/nph-zms?monitor=20&auth=dd89cf2f5c7db76ed9c208d0a2dbc114&connkey=649500
After stopping:
http://192.168.111.245/zm/index.php?view=watch&mid=20&mode=single
After subsequent start:
http://192.168.111.245:30020/zm/cgi-bin/nph-zms?monitor=20&auth=dd89cf2f5c7db76ed9c208d0a2dbc114&connkey=649500

connkey does not change

Yes, I tried changing the connkey and it helped!

[IgorA100]

thing we need to check is if stop is actually stopping the zms process (it should).

No, zms process continues to consume resources even if you do not execute stream.src = '';
That is, it does not stop.
In this case, the request to stop looks like this:
http://192.168.111.245:30020/zm/index.php?auth=dd89cf2f5c7db76ed9c208d0a2dbc114&view=request&request=stream&connkey=151785&command=3

[connortechnology]

Are you using apache or nginx or something else?
I have seen cases under non-apache envs where zms doesn't get SIGPIPE. So it never knows to exit. Which is weird, but is what I have seen. Under apache it generally gets SIGPIPE and dies.

So it is important if you want zms to exit cleanly, to send the QUIT command as well as src='';

[IgorA100]

I created a fix for #4413
Because now in some cases the CMD_STOP command was not sent via AJAX.
But sending the command has not affected ZMS stopping yet.
This is due to the implementation of player switching.
I use Apache on Ubuntu.

[connortechnology]

One thing I don't like is how src=''; results in a broken image link. I'm thinking we should set it to a 1px blank image instead.

[IgorA100]

One thing I don't like is how src=''; results in a broken image link. I'm thinking we should set it to a 1px blank image instead.

I don't like it either. I agree with you.

I tried using this.streamCommand(CMD_QUIT); instead of this.streamCommand(CMD_STOP); and the ZMS process is completely killed.
Now I'm wondering if it's necessary to do it sequentially

    this.streamCommand(CMD_QUIT);
   /this.streamCommand(CMD_STOP);

or is it enough just this.streamCommand(CMD_QUIT);

[connortechnology]

Sending CMD_QUIT should be sufficient. CMD_STOP just stops playback, and it lingers waiting for a new command. STOP/PAUSE are actually the same thing, except pause may buffer frames so you can step back.

[connortechnology]

I'm going to push a couple more fixes, but there remains an issue where after STOP, clicking play doesn't start it back up. Beacuse it calls start() instead of play().

[IgorA100]

where after STOP, clicking play doesn't start

Try this: #4414
This fixed the problem. And I didn't even have to change the connkey
Start after stop now works.