Add code to disable individual actions.

config/config.example.yml

@@ -45,9 +45,13 @@
 :login:               [your login name]
 :password:            [your password]
 
-# Disable the default built-in actions
+# Disable all the default built-in actions
 # :disable_default_actions: true
 
+# Disable specific actions for the node
+# Use this if you want to disable a limited number of actions
+# :disabled_actions: ['word_count']
+
 # By default, CloudCrowd looks for installed actions inside the 'actions'
 # subdirectory of this configuration folder. 'actions_path' allows you to load
 # additional actions from a location of your choice.

lib/cloud_crowd/node.rb

@@ -1,57 +1,57 @@
 module CloudCrowd
-  
+
   # A Node is a Sinatra/Thin application that runs a single instance per-machine
-  # It registers with the central server, receives WorkUnits, and forks off 
+  # It registers with the central server, receives WorkUnits, and forks off
   # Workers to process them. The actions are:
   #
   # [get /heartbeat] Returns 200 OK to let monitoring tools know the server's up.
   # [post /work] The central server hits <tt>/work</tt> to dispatch a WorkUnit to this Node.
   class Node < Sinatra::Default
-    
+
     # A Node's default port. You only run a single node per machine, so they
     # can all use the same port without any problems.
     DEFAULT_PORT        = 9063
-    
-    # A list of regex scrapers, which let us extract the one-minute load 
+
+    # A list of regex scrapers, which let us extract the one-minute load
     # average and the amount of free memory on different flavors of UNIX.
-    
+
     SCRAPE_UPTIME       = /\d+\.\d+/
     SCRAPE_LINUX_MEMORY = /MemFree:\s+(\d+) kB/
-    SCRAPE_MAC_MEMORY   = /Pages free:\s+(\d+)./   
+    SCRAPE_MAC_MEMORY   = /Pages free:\s+(\d+)./
     SCRAPE_MAC_PAGE     = /page size of (\d+) bytes/
-    
+
     # The interval at which the node monitors the machine's load and memory use
     # (if configured to do so in config.yml).
     MONITOR_INTERVAL    = 3
-    
+
     # The interval at which the node regularly checks in with central (5 min).
     CHECK_IN_INTERVAL   = 300
-    
+
     # The response sent back when this node is overloaded.
     OVERLOADED_MESSAGE  = 'Node Overloaded'
-    
+
     attr_reader :enabled_actions, :host, :port, :central
-            
+
     set :root, ROOT
     set :authorization_realm, "CloudCrowd"
-    
+
     helpers Helpers
-    
+
     # methodoverride allows the _method param.
     enable :methodoverride
-    
+
     # Enabling HTTP Authentication turns it on for all requests.
     # This works the same way as in the central CloudCrowd::Server.
     before do
       login_required if CloudCrowd.config[:http_authentication]
     end
-    
-    # To monitor a Node with Monit, God, Nagios, or another tool, you can hit 
+
+    # To monitor a Node with Monit, God, Nagios, or another tool, you can hit
     # /heartbeat to make sure its still online.
     get '/heartbeat' do
       "buh-bump"
     end
-    
+
     # Posts a WorkUnit to this Node. Forks a Worker and returns the process id.
     # Returns a 503 if this Node is overloaded.
     post '/work' do
@@ -61,22 +61,22 @@ class Node < Sinatra::Default
       Process.detach(pid)
       json :pid => pid
     end
-    
+
     # When creating a node, specify the port it should run on.
     def initialize(port=nil, daemon=false)
       require 'json'
       CloudCrowd.identity = :node
       @central          = CloudCrowd.central_server
       @host             = Socket.gethostname
-      @enabled_actions  = CloudCrowd.actions.keys
+      @enabled_actions  = CloudCrowd.actions.keys - (CloudCrowd.config[:disabled_actions] || [])
       @port             = port || DEFAULT_PORT
       @daemon           = daemon
       @overloaded       = false
       @max_load         = CloudCrowd.config[:max_load]
       @min_memory       = CloudCrowd.config[:min_free_memory]
       start unless test?
     end
-    
+
     # Starting up a Node registers with the central server and begins to listen
     # for incoming WorkUnits.
     def start
@@ -94,9 +94,9 @@ def start
       monitor_system if @max_load || @min_memory
       @server_thread.join
     end
-    
-    # Checking in with the central server informs it of the location and 
-    # configuration of this Node. If it can't check-in, there's no point in 
+
+    # Checking in with the central server informs it of the location and
+    # configuration of this Node. If it can't check-in, there's no point in
     # starting.
     def check_in(critical=false)
       @central["/node/#{@host}"].put(
@@ -109,31 +109,31 @@ def check_in(critical=false)
       puts "Failed to connect to the central server (#{@central.to_s})."
       raise SystemExit if critical
     end
-    
+
     # Before exiting, the Node checks out with the central server, releasing all
     # of its WorkUnits for other Nodes to handle
     def check_out
       @central["/node/#{@host}"].delete
     end
-    
+
     # Lazy-initialize the asset_store, preferably after the Node has launched.
     def asset_store
       @asset_store ||= AssetStore.new
     end
-    
-    # Is the node overloaded? If configured, checks if the load average is 
+
+    # Is the node overloaded? If configured, checks if the load average is
     # greater than 'max_load', or if the available RAM is less than
     # 'min_free_memory'.
     def overloaded?
       (@max_load && load_average > @max_load) ||
       (@min_memory && free_memory < @min_memory)
     end
-    
+
     # The current one-minute load average.
     def load_average
       `uptime`.match(SCRAPE_UPTIME).to_s.to_f
     end
-    
+
     # The current amount of free memory in megabytes.
     def free_memory
       case RUBY_PLATFORM
@@ -147,12 +147,12 @@ def free_memory
         raise NotImplementedError, "'min_free_memory' is not yet implemented on your platform"
       end
     end
-    
-    
+
+
     private
-    
-    # Launch a monitoring thread that periodically checks the node's load 
-    # average and the amount of free memory remaining. If we transition out of 
+
+    # Launch a monitoring thread that periodically checks the node's load
+    # average and the amount of free memory remaining. If we transition out of
     # the overloaded state, let central know.
     def monitor_system
       @monitor_thread = Thread.new do
@@ -164,9 +164,9 @@ def monitor_system
         end
       end
     end
-    
-    # If communication is interrupted for external reasons, the central server 
-    # will assume that the node has gone down. Checking in will let central know 
+
+    # If communication is interrupted for external reasons, the central server
+    # will assume that the node has gone down. Checking in will let central know
     # it's still online.
     def check_in_periodically
       @check_in_thread = Thread.new do
@@ -176,15 +176,15 @@ def check_in_periodically
         end
       end
     end
-    
+
     # Trap exit signals in order to shut down cleanly.
     def trap_signals
       Signal.trap('QUIT') { shut_down }
       Signal.trap('INT')  { shut_down }
       Signal.trap('KILL') { shut_down }
       Signal.trap('TERM') { shut_down }
     end
-    
+
     # At shut down, de-register with the central server before exiting.
     def shut_down
       @check_in_thread.kill if @check_in_thread
@@ -193,7 +193,7 @@ def shut_down
       @server_thread.kill if @server_thread
       Process.exit
     end
-    
+
   end
-  
+
 end