initial prototype

sbin/symbiosis-dns-generate

@@ -0,0 +1,258 @@
+#!/usr/bin/ruby
+#
+# NAME
+#
+#   symbiosis-dns-generate - Generate DNS snippet files for Symbiosis domains.
+#
+# USAGE
+#
+#   symbiosis-dns-generate [ --sleep SEC | -s SEC ] [ --template TEMPLATE | -t TEMPLATE ]
+#          [ --force | -f ] [ --verbose | -v ]
+#          [ --help | -h ] [ DOMAIN ]
+#
+# SYNOPSIS
+#
+#   --sleep SEC            sleep for a random amount of time before doing
+#                          anything, up to a maximum of SEC seconds.
+#
+#   --template TEMPLATE    Specify an alternative template file to read.
+#
+#   --force              Force the re-creation of all DNS data.
+#   --upload             Force the upload of all DNS data.
+#   --help               Show the help information for this script.
+#   --verbose            Show debugging information.
+#
+# DETAILS
+#
+# This script is designed to iterate over the domains hosted upon a Symbiosis
+# system, and create TinyDNS snippets for each one. This can then be uploaded
+# to the Bytemark content DNS service.
+#
+# Domains can also be specified manually on the command line, in which case
+# only those domains will be processed.
+#
+# AUTHOR
+#
+# Steve Kemp <steve@bytemark.co.uk>
+# Adapted for Mythic Beasts by Ben Charlton <ben@spod.cx>
+#
+
+
+require 'getoptlong'
+
+
+#
+#  Entry point to the code
+#
+force    = false
+help     = false
+$VERBOSE  = false
+
+#
+# Do we need to re-upload the data?
+#
+upload=true
+
+#
+# The root directory -- '/' by default.
+#
+root             = "/"
+dns_template     = nil
+sleep_for        = nil
+
+opts = GetoptLong.new(
+         [ '--force',    '-f', GetoptLong::NO_ARGUMENT ],
+         [ '--help',     '-h', GetoptLong::NO_ARGUMENT ],
+         [ '--sleep',    '-s', GetoptLong::REQUIRED_ARGUMENT ],
+         [ '--template', '-t', GetoptLong::REQUIRED_ARGUMENT ],
+         [ '--upload',   '-u', GetoptLong::NO_ARGUMENT ],
+         [ '--verbose',  '-v', GetoptLong::NO_ARGUMENT ]
+       )
+
+opts.each do |opt, arg|
+  case opt
+  when '--help'
+    help = true
+  when '--verbose'
+    $VERBOSE = true
+  when '--template'
+    dns_template = arg
+  when '--sleep'
+    sleep_for = arg
+  when '--root'
+    root = arg
+  when '--force'
+    force = true
+  when '--upload'
+    upload = true
+  end
+end
+
+#
+# CAUTION! Here be quality kode.
+#
+if help
+  # Open the file, stripping the shebang line
+  lines = File.open(__FILE__){|fh| fh.readlines}[2..-1]
+
+  lines.each do |line|
+    line.chomp!
+    break if line.empty?
+    puts line[2..-1].to_s
+  end
+
+  exit 0
+end
+
+def verbose(s)
+  puts s if $VERBOSE
+end
+
+require 'symbiosis/domains'
+require 'symbiosis/domain'
+require 'symbiosis/config_files/mythicdns'
+
+#
+# Set the default paths.
+#
+dns_template    = File.join(root, "/etc/symbiosis/dns.d/mythicdns.template.erb") if dns_template.nil?
+
+#
+# Bail out if the template is missing
+#
+unless File.file?(dns_template)
+  verbose "Unable generate DNS data because the template #{dns_template.inspect} is missing."
+  exit 1
+end
+
+#
+# Work out if we need to sleep.
+#
+unless sleep_for.nil?
+  sleep_for = (sleep_for =~ /(\d+)/ ? rand($1.to_i) : 0)
+  verbose "Sleeping for #{sleep_for}s before starting work"
+  sleep sleep_for
+end
+
+#
+# Any arguments on the command line specify which domains to do.
+#
+domains_to_configure = ARGV
+string_to_hash = []
+
+#
+# For each domain.
+#
+Symbiosis::Domains.each do |domain|
+
+  verbose "Domain: #{domain.name} "
+
+  next unless domains_to_configure.empty? or domains_to_configure.include?(domain.name)
+
+  begin
+    output        = File.join(domain.config_dir, "dns", domain.name+".txt")
+    output_dir    = File.dirname(output)
+    config        = Symbiosis::ConfigFiles::Tinydns.new(output, "#")
+    config.domain   = domain
+    config.template = dns_template
+
+    #
+    # Should the snippet be created?
+    #
+    do_create = false
+
+    if ( force )
+      verbose "\tForcing re-creation of snippet due to --force."
+      do_create = true
+
+    elsif config.exists?
+
+      if config.changed?
+        verbose "\tNot updating snippet, as it has been edited by hand."
+
+      elsif config.outdated?
+        verbose "\tRe-creating snippet as it is out of date."
+        do_create = true
+
+      else
+        verbose "\tDomain already present and up-to date."
+
+      end
+
+    else
+      verbose "\tConfiguring site for the first time"
+      do_create = true
+
+    end
+
+    #
+    #
+    # Check the TinyDNS syntax.. TODO!
+    #
+    if do_create
+      if config.ok?
+
+        verbose "\tWriting snippet to #{output}"
+
+        #
+        # Create directory with the same ownership as the parent
+        #
+        domain.create_dir(output_dir) unless File.exist?(output_dir)
+
+        #
+        # Write the snippet
+        #
+        config.write
+
+        #
+        # Make sure the ownership is correct.
+        #
+        File.chown(domain.uid, domain.gid, config.filename)
+
+      else
+        verbose "\tThe new DNS snippet is invalid -- no changes have been made."
+      end
+    end
+
+
+    #
+    # Rescue errors for this domain, but continue for others.
+    #
+  rescue StandardError => err
+    verbose "\tUnable to create DNS data for #{domain.name} because #{err.to_s}"
+    verbose "\t"+err.backtrace.join("\n\t")
+  end
+end
+
+begin
+
+  if upload
+    upload_script = "/usr/sbin/symbiosis-mythic-dns"
+
+    verbose "Uploading using #{upload_script}"
+
+    IO.popen("#{upload_script} 2>&1","r") do |io|
+      while !io.eof? do
+        verbose io.readline
+      end
+    end
+
+    unless 0 == $?
+      raise StandardError, "#{upload_script.inspect} failed."
+    end
+
+  else
+    verbose "No need to upload as no changes in the data have been detected."
+  end
+rescue StandardError => err
+  warn "Unable to upload DNS data because #{err.to_s}"
+  verbose "\t"+err.backtrace.join("\n\t")
+  exit 1
+end
+
+#
+#  All done.
+#
+
+exit 0
+