castnow_control

Some scripts to integrate and control castnow via openHAB.

Requirements

Install screen via your pakage manager. (e.g. sudo apt-get install screen)

Get castnow from GitHub: https://github.com/xat/castnow

Here is how it is done on Rasbian Jessie on RaspberryPi.

Add the repository for nodejs

curl -sL https://deb.nodesource.com/setup | sudo bash -

Install nodejs and screen.

sudo apt-get install nodejs screen

Install castnow

sudo npm install castnow -g

Install

Clone this repository or copy the files to your system (e.g. /opt/castnow_control)

Copy or rename the default configuration from castnow_scripts.cfg.defaultto castnow_scripts.cfgand define your own values.

Chown the folder and files to the same user that will run the scripts. (e.g. openhab)

cd /opt
sudo git clone https://github.com/CWempe/castnow_control.git
cd castnow_control
cp castnow_scripts.cfg.default castnow_scripts.cfg
chown -R openhab:openhab /opt/castnow_control

Create a cronjob for castnow_watchdog.shor execute it via watch.

Let the watchdog run every few seconds (depending on the available performance of your system).

Integrating in openHAB

exec binding

Install the exec binding. On rasbian:

sudo apt-get install openhab-addon-binding-exec

chromecast.items

String  CastState       "Status [%s]"   { exec="<[/opt/castnow_control/castnow_get_state.sh state:1000:]" }
String  CastSource      "Title [%s]"    { exec="<[/opt/castnow_control/castnow_get_state.sh source:1000:]" }

String  CastDown        "Volume -"      {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh down]",     "autoupdate"="false"}
String  CastUp          "Volume +"      {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh up]",       "autoupdate"="false"}
String  CastMute        "Mute"          {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh mute]",     "autoupdate"="false"}

String  CastPause       "Pause"         {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh pause]",    "autoupdate"="false"}
String  CastStop        "Stop"  {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh stop]",     "autoupdate"="false"}
String  CastLeft        "Seek backwards"        {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh left]",     "autoupdate"="false"}
String  CastRight       "Seek forward"          {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh right]",    "autoupdate"="false"}

String  CastQuit        "Quit"  {exec=">[TOGGLE:/opt/castnow_control/castnow_send_command.sh quit]",     "autoupdate"="false"}

chromecast.sitemap

sitemap chromecast label="Chromecast"
{
    Frame label="State" {
        Text    item=CastState
        Text    item=CastSource
    }
    Frame label="Control" {
        Switch  item=CastDown
        Switch  item=CastUp
        Switch  item=CastMute

        Switch  item=CastPause
        Switch  item=CastStop
        Switch  item=CastLeft
        Switch  item=CastRight

        Switch  item=CastQuit
    }
}

What do the scripts do?

castnow_get_state.sh

This script reads the output from castnow and returns the Status and/or the Source (e.g. title of video).

castnow_send_command.sh

This script send commands (e.g. play/pause, mute, stop, Vol+, ...) to castnow.

castnow_watchdog.sh

This script (re)starts castnow if it is not running or lost connection to your Chromecast device.

How it works

Because castnow only runs in the foreground in the command line we need a way to put it back in the background and let it run as some kind of deamon.

That is way these scripts use screen.

To get the current state we take a hardcopyof the screen/castnow output, save it to a file and parse it.

We use the -X stufffunction of screento send keypresses to castnow.

Limitations/to-do

• open/start streams via castnow
• support multiple Chromecast devices at the same time
• push buttons do not work correctly in HABdroid and iOS app see: https://community.openhab.org/t/habdroid-not-supporting-push-buttons-toggle/4604