Dashboard Client

The idea of this repo is to be a redesign of the remotechrome code. Each TV will run Consul which will connect to the admin server as well as this application. This app watches paths in Consul and if they change it will call Chromium dev tools to either open a URL or reload the browser.

Previously, I thought about using confd to watch Consul and then have confd execute a script but I realized that this app could do the same work with less moving parts.

Configuration

[chrome]
host = "localhost"
port = 9222

[consul]
address = "localhost:8500"
scheme = "http"
datacenter = "datacenter1"
action = "foo/action"
newurl = "foo/url"
runningurl = "foo/current"

[delay]
interval = 1000

Config Section - Chrome

The address and port the Chromium dev tools are listening on. localhost and 9222 are the defaults.

Config Section - Consul

address is the address and port of the local Consul server.

scheme is the http protocol used to talk to the Consul server. Since it is only talking to the localhost, http is being used.

datacenter is the Consul configured datacenter

action is the path the application will watch for action commands. If the application were called tv1 the path would be tv1/action. The TV name is where the dashboard-admin will write the action. At the moment the only valid actions are open and reload

newurl is the path the application will watch for what URL to open in the browser. If the application were called tv1 the path would be tv1/url. The application keeps the currently running URL stored in runningURL and with compare the value stored in tv1/url to runningURL if they match the URL will not be loaded. If they do not match the URL will be opened in the browser.

runningurl is the path the application will write the currently running URL. It is possible that the new URL and the running URL could be different. A future plan is to setup a temp URL path so that a URL would be shown for some short amount of time and after that time the value of runningurl could be used to reopen the normal path the TV should show.

Config Section - Delay

interval the number of milliseconds the application will wait before looking at the Consul paths to see if they have changed.

Execution

% ./dashboard-client -help
Usage of ./dashboard-client:
-conf string
Config file chromium, Consul, delay interval.

% ./dashboard-client -conf config.toml

Starting Chromium

#!/usr/bin/env bash
CHROME_DATA_DIR=$(mktemp -d)
trap "rm -rf ${CHROME_DATA_DIR}" SIGINT SIGTERM EXIT

# this will take over your screen
/usr/bin/chromium --remote-debugging-port=9222 --user-data-dir="${CHROME_DATA_DIR}" --disable-infobars --kiosk "about:blank"

# to test without it chromium going full screen
#/usr/bin/chromium --remote-debugging-port=9222 --user-data-dir="${CHROME_DATA_DIR}"

References

Dependencies

https://github.com/BurntSushi/toml

https://github.com/hashicorp/consul/api

https://github.com/raff/godet

https://consul.io

Code being superseded

https://github.com/mikeplem/remotechrome

Testing

Consul Setup

Here is a simple Consul config

{
"datacenter": "datacenter1",
"data_dir": "/tmp/consul",
}

mkdir -p /tmp/consul

Run Consul like this

./consul agent -dev -config-file test.hcl

Since we are in dev mode nothing exists in Consul so create test values

./consul kv put foo/url https://osu.edu
./consul kv put foo/action open

Chromium Setup

Use the script above to start Chromium but make sure it does not go full screen