Document more scripts and introduce a config file.

.gitignore

@@ -0,0 +1,2 @@
+.DS_Store
+config.yml

README.md

@@ -56,6 +56,30 @@ You must also make sure your filesystem is mounted with ACL support, e.g.:
 
 Don't forget to update /etc/fstab too.
 
+### display-queue - Display statistics for local RabbitMQ queues
+
+This tool displays statistics for RabbitMQ queues in a more friendly formatter than `rabbitmqctl list_queues`. The meanings of the columns are as follows:
+
+ * Messages - Total number of messages in the queue. Equal to `Ready + Unack`.
+ * Ready - Number of messages in the queue not yet consumed.
+ * Unack - Number of messages in the queue that have been consumed, but not yet acknowledged.
+ * Consumers - Number of consumers subscribed to this queue.
+ * Memory - The amount of memory that RabbitMQ is using for this queue.
+
+### watch-queue - Display changes in local RabbitMQ queues
+
+`watch-queue` combines the `watch` tool with `display-queue`. It continuously displays the latest queue statistics and highlights changes.
+
+### purge-queue - Removes all messages from a local RabbitMQ queue
+
+`purge-queue` removes all messages from given given RabbitMQ queue. It connects to a RabbitMQ server on localhost on the default port. Note that consumed-but-unacknowledged messages in the queue cannot be removed.
+
+    purge-queue <QUEUE NAME HERE>
+
+### truncate
+
+Truncates the all passed files to 0 bytes.
+
 ### silcence-unless-failed
 
 Runs the given command but only print its output (both STDOUT and STDERR) if its exit code is non-zero. The script's own exit code is the same as the command's exit code.

config.yml.example

@@ -0,0 +1,9 @@
+git-gc-repos:
+  glob:
+    - /u/apps/**/.git
+
+notify-if-queue-becomes-large:
+  threshold: 1000
+  to: your@email.com
+  from: your@server.com
+  subject: Queue going out of control

gc-git-repos

@@ -1,20 +1,14 @@
 #!/usr/bin/env ruby
-# This script is automatically called in a cron job by root.
+require File.expand_path(File.dirname(__FILE__) + '/shared')
 require 'etc'
 
-DIRS = Dir[
-	"/u/apps/**/.git"
-]
+DIRS = Dir[*config(:glob)]
 DIRS.each do |dir|
 	puts "# Garbage collecting #{dir}"
 	Dir.chdir(dir) do
 		stat = File.stat(dir)
 		username = Etc.getpwuid(stat.uid).name
-		command = "su -c 'git gc' #{username}"
-		puts command
-		if !system(command)
-			abort "'git gc' failed"
-		end
+		quiet_sh "su -c 'git gc' #{username}"
 	end
 	puts
 end

notify-if-queue-becomes-large

@@ -1,5 +1,9 @@
 #!/usr/bin/env ruby
-THRESHOLD=1000
+require File.expand_path(File.dirname(__FILE__) + '/shared')
+THRESHOLD = config(:threshold)
+FROM      = config(:from)
+TO        = config(:to)
+SUBJECT   = config(:subject)
 
 warnings = []
 `rabbitmqctl list_queues -q name messages`.split("\n").each do |line|
@@ -12,9 +16,9 @@ end
 
 if !warnings.empty?
 	IO.popen("sendmail -t", "w") do |f|
-		f.puts "To: info@phusion.nl"
-		f.puts "From: noreply@unionstationapp.com"
-		f.puts "Subject: [Union Station] Queue going out of control"
+		f.puts "To: #{TO}"
+		f.puts "From: #{FROM}"
+		f.puts "Subject: #{SUBJECT}"
 		f.puts
 		f.puts warnings.join("\n")
 	end

shared.rb

@@ -3,9 +3,12 @@
 
 def sh(command, *args)
 	puts "# #{command} #{args.join(' ')}"
+	quiet_sh(command, *args)
+end
+
+def quiet_sh(command, *args)
 	if !system(command, *args)
-		STDERR.puts "*** ERROR"
-		exit 1
+		abort "*** COMMAND FAILED: #{command} #{args.join(' ')}".strip
 	end
 end
 
@@ -35,3 +38,22 @@ def pv_or_cat
 		return 'cat'
 	end
 end
+
+def load_config
+	require 'yaml'
+	if !File.exist?("#{TOOLS_DIR}/config.yml")
+		abort "*** ERROR: you must create a #{TOOLS_DIR}/config.yml. " +
+			"Please see #{TOOLS_DIR}/config.yml.example for an example."
+	end
+	all_config = YAML.load_file("#{TOOLS_DIR}/config.yml")
+	$TOOL_CONFIG = all_config[File.basename($0)]
+end
+
+def config(name)
+	load_config if !$TOOL_CONFIG
+	value = $TOOL_CONFIG[name.to_s]
+	if !value
+		abort "*** ERROR: configuration option #{File.basename($0)}.#{name} not set."
+	end
+	return value
+end