Stream Status - Revision history

Kieran: updated script

2020-02-22T00:05:00Z

updated script

Kieran at 23:42, 21 February 2020

2020-02-21T23:42:47Z

Kieran: /* Stream Status */

2020-02-21T23:41:37Z

Stream Status

Kieran: Created page with "= Stream Status = The Stream Status tool is comprised of a command that checks for stream silence and a PHP page that reports this for the uptime monitor. == Command == The c..."

2020-02-21T23:40:50Z

Created page with "= Stream Status = The Stream Status tool is comprised of a command that checks for stream silence and a PHP page that reports this for the uptime monitor. == Command == The c..."

New page

= Stream Status =
The Stream Status tool is comprised of a command that checks for stream silence and a PHP page that reports this for the uptime monitor.

== Command ==
The command is as follows:
<syntaxhighlight lang="bash">
ffmpeg -i http://garfield.standrewsradio.com:8080/stream/1.mp3 -y -nostats -loglevel 0 -f mp3 -t 00:00.05 - | sox -t mp3 - -n stat 2>&1 | grep "Maximum amplitude" | cut -d' ' -f 7
</syntaxhighlight>

This is split into four different parts, each operating on the output of the part before:

# <syntaxhighlight lang="bash" inline>ffmpeg -i http://garfield.standrewsradio.com:8080/stream/1.mp3 -y -nostats -loglevel 0 -f mp3 -t 00:00.5 -</syntaxhighlight>: silently records half a second of the stream as an mp3.
# <syntaxhighlight lang="bash" inline>sox -t mp3 - -n stat 2>&1</syntaxhighlight>: using sox, read the MP3 recording and get some statistics on it, piping stderr and stdout into stdout.
# <syntaxhighlight lang="bash" inline>grep "Maximum amplitude"</syntaxhighlight>: gets the line of the output that contains information about the maximum amplitude.
# <syntaxhighlight lang="bash" inline>cut -d' ' -f 7</syntaxhighlight>: cuts the input into parts around spaces and returns the 7th part (this is the maximum amplitude in seconds).

== PHP ==
The PHP script is as follows:
<syntaxhighlight lang="php">
<?php
$output = exec("<the command>");
$val = floatval($output);

if ($val === 0.0) {
http_response_code(503);
} else {
echo "all good :)";
http_response_code(200);
}
</syntaxhighlight>

This script simply gets the output of the command that is run and checks the value. If it is 0, it returns a server error response code for the uptime robot to detect.

← Older revision		Revision as of 23:42, 21 February 2020
Line 1:		Line 1:
−	The Stream Status tool is comprised of a command that checks for stream silence and a PHP page that reports this for the uptime monitor.	+	The Stream Status tool is comprised of a command that checks for stream silence and a PHP page that reports this for the uptime monitor. The script is hosted at [https://standrewsradio.com/stream-status.php standrewsradio.com/stream-status.php].

	== Command ==		== Command ==

@@ Line 18: / Line 18: @@
 <syntaxhighlight lang="php">
 <?php
 $output = exec("<the command>");
 $val = floatval($output);
-if ($val === 0.0) {
+if ($val < 0.00025) {
      http_response_code(503);
 } else {
-     echo "all good :)";
+     echo "all good :) max amplitude was $val!";
      http_response_code(200);
+}
 </syntaxhighlight>
-This script simply gets the output of the command that is run and checks the value. If it is 0, it returns a server error response code for the uptime robot to detect.
+This script simply gets the output of the command that is run and checks the value. If it less than 0.00025, it returns a server error response code for the uptime robot to detect. This number has been chosen completely arbitrarily based on the fact that "silence" appears to fluctuate between 0.0001 and 0.0002.

@@ Line 1: / Line 1: @@
 The Stream Status tool is comprised of a command that checks for stream silence and a PHP page that reports this for the uptime monitor.
@@ Line 5: / Line 4: @@
 The command is as follows:
 <syntaxhighlight lang="bash">
-ffmpeg -i http://garfield.standrewsradio.com:8080/stream/1.mp3 -y -nostats -loglevel 0 -f mp3 -t 00:00.05 - | sox -t mp3 - -n stat 2>&1 | grep "Maximum amplitude" | cut -d' ' -f 7
+ffmpeg -i http://garfield.standrewsradio.com:8080/stream/1.mp3 -y -nostats -loglevel 0 -f mp3 -t 00:00.5 - | sox -t mp3 - -n stat 2>&1 | grep "Maximum amplitude" | cut -d' ' -f 7
 </syntaxhighlight>