raise an exception if retry is called when no transaction is open

lib/kestrel/client/transactional.rb

@@ -4,10 +4,14 @@ class Kestrel::Client::Transactional < Kestrel::Client::Proxy
   # multiple queues.
   class MultipleQueueException < StandardError; end
 
+  # Raised when a caller attempts to retry a job if
+  # there is no current open transaction
+  class NoOpenTransaction < StandardError; end
+
   class RetryableJob < Struct.new(:retries, :job); end
 
   # Number of times to retry a job before giving up
-  DEFAULT_RETRIES = 100
+  DEFAULT_RETRIES = 10
 
   # Pct. of the time during 'normal' processing we check the error queue first
   ERROR_PROCESSING_RATE = 0.1
@@ -39,6 +43,9 @@ def initialize(client, max_retries = nil, error_rate = nil)
   # ==== Returns
   # Job, possibly retryable, or nil
   #
+  # ==== Raises
+  # MultipleQueueException
+  #
   def get(key, opts = {})
     raise MultipleQueueException if current_queue && key != current_queue
 
@@ -69,20 +76,21 @@ def close_last_transaction #:nodoc:
   # retry. If the job has been retried DEFAULT_RETRIES times,
   # gives up entirely.
   #
+  # ==== Parameters
+  # item (optional):: if specified, the job set to the error
+  #                   queue with the given payload instead of what
+  #                   was originally fetched.
+  #
   # ==== Returns
   # Boolean:: true if the job is enqueued in the retry queue, false otherwise
   #
+  # ==== Raises
+  # NoOpenTransaction
   #
   def retry(item = nil)
-    job =
-      if item
-        current_retries = (@job ? @job.retries : 0)
-        RetryableJob.new(current_retries, item)
-      else
-        @job.dup
-      end
-
-    return unless job
+    raise NoOpenTransaction unless @last_read_queue
+
+    job = item ? RetryableJob.new(@job.retries, item) : @job.dup
 
     job.retries += 1
 

spec/kestrel/client/transactional_spec.rb

@@ -18,6 +18,7 @@ def get_job
       returns = [:mcguffin]
       stub(@raw_kestrel_client).get(@queue, anything) { returns.shift }
       stub(@raw_kestrel_client).get(@queue + "_errors", anything)
+
       mock(@raw_kestrel_client).get_from_last(@queue + "/close")
 
       get_job.should == :mcguffin
@@ -29,6 +30,7 @@ def get_job
       returns = [Kestrel::Client::Transactional::RetryableJob.new(1, :mcguffin)]
       stub(@raw_kestrel_client).get(@queue + "_errors", anything) { returns.shift }
       stub(@raw_kestrel_client).get(@queue, anything)
+
       mock(@raw_kestrel_client).get_from_last(@queue + "_errors/close")
 
       get_job.should == :mcguffin
@@ -40,6 +42,7 @@ def get_job
       returns = [:mcguffin]
       stub(@raw_kestrel_client).get(@queue, anything) { returns.shift }
       stub(@raw_kestrel_client).get(@queue + "_errors", anything)
+
       mock(@raw_kestrel_client).set(@queue + "_errors", anything) do |q,j|
         j.retries.should == 1
         j.job.should == :mcguffin
@@ -155,6 +158,16 @@ def get_job
         @kestrel.get(@queue)
       end
 
+      it "raises an exception if called when there is no open transaction" do
+        @kestrel.close_last_transaction
+        lambda { @kestrel.retry }.should raise_error(Kestrel::Client::Transactional::NoOpenTransaction)
+      end
+
+      it "raises an exception if retry has already been called" do
+        @kestrel.retry
+        lambda { @kestrel.retry }.should raise_error(Kestrel::Client::Transactional::NoOpenTransaction)
+      end
+
       it "enqueues a fresh failed job to the errors queue with a retry count" do
         mock(@raw_kestrel_client).set(@queue + "_errors", anything) do |queue, job|
           job.retries.should == 1