Refactor, fix rubocop lint errors

.rubocop.yml

@@ -0,0 +1,4 @@
+Metrics/MethodLength:
+  Max: 25
+Metrics/AbcSize:
+  Enabled: false

unipoly-mlmmj-ldap-sync

@@ -3,120 +3,169 @@
 require 'toml'
 require 'net/ldap'
 
-@configuration_file = "/etc/unipoly-mlmmj-ldap-sync.toml"
+@configuration_file = '/etc/unipoly-mlmmj-ldap-sync.toml'
+@configuration = nil
 
 def read_configuration(path)
-  TOML.load_file(path)
+  begin
+    TOML.load_file(path)
+  rescue Errno::ENOENT => raisedError
+    puts "Could not open configuration file: #{raisedError}"
+    exit(1)
+  end
 end
 
 def connect_ldap(conf)
   conn = Net::LDAP.new(
-    :host => conf["ldap"]["host"],
-    :port => conf["ldap"]["port"],
-    :auth => {
-      :method => :simple,
-      :username => conf["ldap"]["auth"]["username"],
-      :password => conf["ldap"]["auth"]["password"]
-    })
+    host: conf['ldap']['host'],
+    port: conf['ldap']['port'],
+    auth: {
+      method: :simple,
+      username: @configuration['ldap']['auth']['username'],
+      password: @configuration['ldap']['auth']['password']
+    }
+  )
 
   begin
     if conn.bind
       conn
     else
       puts "Failed to authenticate against LDAP server: \
-      #{conf["ldap"]["host"]}:#{conf["ldap"]["port"]}"
+      #{conf['ldap']['host']}:#{conf['ldap']['port']}"
       exit(1)
     end
-  rescue
-      puts "Failed to contact LDAP server: \
-      #{conf["ldap"]["host"]}:#{conf["ldap"]["port"]}"
-      exit(1)
+  rescue LdapError => raised_error
+    puts "Failed to contact LDAP server: \
+      #{conf['ldap']['host']}:#{conf['ldap']['port']}"
+    puts raised_error
+    exit(1)
   end
 end
 
+def get_mlmmj_subscribers(list_name)
+  mlmmj_list_binary = @configuration['mlmmj']['list_binary']
+  mlmmj_basepath = @configuration['mlmmj']['basepath']
+  list = "#{mlmmj_basepath}/#{list_name}@#{@configuration['domain']}"
+
+  unless File.executable?(mlmmj_list_binary)
+    puts "could not execute #{mlmmj_list_binary}"
+    exit(1)
+  end
+
+  # Execute mlmmj-list and check whether it exited successfuly
+  raw = `#{mlmmj_list_binary} -L #{list} -s`
+  unless $CHILD_STATUS.exitstatus.zero?
+    puts 'FAIL'
+    exit(1)
+  end
+
+  # Return a list of mail addresses.
+  raw.split("\n")
+end
+
+def add_subscriber_to(list_name, subscribers, list, addr)
+  if subscribers.include?(addr)
+    # The address is already subscribed to the list: we're done with it.
+    subscribers.delete(addr)
+  else
+    # The address is not subscribed to the list yet.
+    print "Adding #{addr}... "
+
+    # Since the configuration file doesn't say we have to add new subscribers
+    # to this list, we ignore this action.
+    unless @configuration['lists_add'].include?(list_name)
+      puts 'IGNORED'
+      return
+    end
+
+    # Subscribe the address to the list.
+    mlmmj_sub_binary = @configuration['mlmmj']['sub_binary']
+    `#{mlmmj_sub_binary} -L #{list} -a #{addr} -q -f -s`
+    if $CHILD_STATUS.exitstatus.zero?
+      puts 'OK'
+    else
+      puts 'FAILED'
+    end
+  end
+end
+
+def remove_subscriber_from(list_name, list, addr)
+  print "Removing #{addr}... "
+
+  # We ignore this action if the configuration file doesn't say we are allowed
+  # to remove addresses from this list.
+  unless conf['lists_remove'].include?(list_name)
+    puts 'IGNORED'
+    return
+  end
+
+  # Unsubscribe the address from the list.
+  mlmmj_unsub_binary = conf['mlmmj']['unsub_binary']
+  `#{mlmmj_unsub_binary} -L #{list} -a #{s} -q -s`
+  if $CHILD_STATUS.exitstatus.zero?
+    puts 'OK'
+  else
+    puts 'FAILED'
+  end
+end
+
+def sync_list(list_name, ldap_group_entry)
+  # Members are formatted as
+  # 'mail=user@domain.tld,ou=Users,dc=unipoly,dc=epfl,dc=ch': we extract the
+  # mail address.
+  ldap_members = ldap_group_entry.uniquemember.map do |dn|
+    /mail=([^,]+),/.match(dn).values_at(1).first.downcase
+  end
+  puts "Found #{entry.dn} with #{members.size} members"
+
+  # Extract mail addresses from Mlmmj
+  print 'Searchin mlmmj... '
+  mlmmj_subscribers = get_mlmmj_subscribers(list_name)
+  puts 'OK'
+  puts "Found #{entry.cn}@#{@configuration['domain']} with #{subscribers.size} \
+  subscribers"
+  print "\n"
+
+  # Add to the subscribers any missing entry
+  # Remove successful matches
+  ldap_members.each do |addr|
+    add_subscriber_to(list_name, subscribers, list, addr)
+  end
+
+  # Remove remaining "subcribers" (= they did not match with LDAP members)
+  mlmmj_subscribers.each do |addr|
+    remove_subscriber_from(list_name, list, addr)
+  end
+  print "\n"
+end
+
 def main
-  conf = read_configuration(@configuration_file)
+  # Parse configuration, bind to LDAP server
+  @configuration = read_configuration(@configuration_file)
   conn = connect_ldap(conf)
 
-  domain = conf["domain"]
-  basetree = conf["ldap"]["lists"]["basetree"]
-  lists = (conf["lists_add"] + conf["lists_remove"]).uniq
-  lists.each do |cn|
-    puts ">> Processing list #{cn}@#{domain}"
+  domain = @configuration['domain']
+  basetree = @configuration['ldap']['lists']['basetree']
+  lists = (@configuration['lists_add'] + @configuration['lists_remove']).uniq
 
-    filter = Net::LDAP::Filter.eq("cn", cn)
+  # Sync Mlmmj lists with LDAP groups
+  lists.each do |list_name|
+    puts ">> Processing list #{list_name}@#{domain}"
+    print 'Searching LDAP... '
 
-    print "Searching LDAP... "
-    match = conn.search(:base => basetree, :filter => filter)
-    if (match.size > 0)
-      entry = match.first
-      members = entry.uniquemember.map do |dn|
-        /mail=([^,]+),/.match(dn).values_at(1).first.downcase
-      end
-
-      puts "OK"
-      puts "Found #{entry.dn} with #{members.size} members"
-
-      print "Searchin mlmmj... "
-      mlmmj_list_binary = conf["mlmmj"]["list_binary"]
-      mlmmj_basepath = conf["mlmmj"]["basepath"]
-      list = "#{mlmmj_basepath}/#{cn}@#{domain}"
-      if (File.executable?(mlmmj_list_binary))
-        raw = %x(#{mlmmj_list_binary} -L #{list} -s)
-
-        if ($?.exitstatus == 0)
-          puts "OK"
-          subscribers = raw.split("\n")
-          puts "Found #{cn}@#{domain} with #{subscribers.size} subscribers"
-          print "\n"
-
-          # Add to the subscribers any missing entry
-          # Remove successful matches
-          members.each do |m|
-            if (subscribers.include?(m))
-               subscribers.delete(m)
-            else
-              print "Adding #{m}... "
-              if (conf["lists_add"].include?(cn))
-                mlmmj_sub_binary = conf["mlmmj"]["sub_binary"]
-                %x(#{mlmmj_sub_binary} -L #{list} -a #{m} -q -f -s)
-                if ($?.exitstatus == 0)
-                  puts "OK"
-                else
-                  puts "FAILED"
-                end
-              else
-                puts "IGNORED"
-              end
-            end
-          end
-
-          # Remove remaining "subcribers" (= they did not match with members)
-          subscribers.each do |s|
-            print "Removing #{s}... "
-            if (conf["lists_remove"].include?(cn))
-              mlmmj_unsub_binary = conf["mlmmj"]["unsub_binary"]
-              %x(#{mlmmj_unsub_binary} -L #{list} -a #{s} -q -s)
-              if ($?.exitstatus == 0)
-                puts "OK"
-              else
-                puts "FAILED"
-              end
-            else
-              puts "IGNORED"
-            end
-          end
-          print "\n"
-        else
-          puts "FAIL"
-        end
-      else
-        puts "could not execute #{mlmmj_list_binary}"
-      end
+    filter = Net::LDAP::Filter.eq('cn', list_name)
+    matched_ldap_groups = conn.search(base: basetree, filter: filter)
+    if matched_ldap_groups.empty?
+      # Could not find matching LDAP group
+      puts 'NOT FOUND'
     else
-      puts "FAIL"
+      puts 'OK'
+      ldap_group_entry = matched_ldap_groups.first
+      sync_list_with(list_name, ldap_group_entry)
     end
   end
 end
 
-main()
+###
+# Execute script:
+main