From c3eb0ea9db42b8ac25263c9b0ab283efc3bf20ae Mon Sep 17 00:00:00 2001
From: Moxie Marlinspike <moxie@thoughtcrime.org>
Date: Tue, 21 Oct 2014 13:50:38 -0700
Subject: [PATCH] Check job requirements are satisfied in between retry
 iterations.

// FREEBIE
---
 .../java/org/whispersystems/jobqueue/Job.java |  9 +++++
 .../whispersystems/jobqueue/JobConsumer.java  | 36 +++++++++++++------
 2 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/jobqueue/src/main/java/org/whispersystems/jobqueue/Job.java b/jobqueue/src/main/java/org/whispersystems/jobqueue/Job.java
index 3a38759225..202f95c993 100644
--- a/jobqueue/src/main/java/org/whispersystems/jobqueue/Job.java
+++ b/jobqueue/src/main/java/org/whispersystems/jobqueue/Job.java
@@ -26,6 +26,7 @@ public abstract class Job implements Serializable {
   private final JobParameters parameters;
 
   private transient long persistentId;
+  private transient int  runIteration;
 
   public Job(JobParameters parameters) {
     this.parameters = parameters;
@@ -71,6 +72,14 @@ public abstract class Job implements Serializable {
     return persistentId;
   }
 
+  public int getRunIteration() {
+    return runIteration;
+  }
+
+  public void setRunIteration(int runIteration) {
+    this.runIteration = runIteration;
+  }
+
   public abstract void onAdded();
   public abstract void onRun() throws Throwable;
   public abstract void onCanceled();
diff --git a/jobqueue/src/main/java/org/whispersystems/jobqueue/JobConsumer.java b/jobqueue/src/main/java/org/whispersystems/jobqueue/JobConsumer.java
index 773a7a874e..4419dc62e3 100644
--- a/jobqueue/src/main/java/org/whispersystems/jobqueue/JobConsumer.java
+++ b/jobqueue/src/main/java/org/whispersystems/jobqueue/JobConsumer.java
@@ -20,6 +20,12 @@ import org.whispersystems.jobqueue.persistence.PersistentStorage;
 
 public class JobConsumer extends Thread {
 
+  enum JobResult {
+    SUCCESS,
+    FAILURE,
+    DEFERRED
+  }
+
   private final JobQueue          jobQueue;
   private final PersistentStorage persistentStorage;
 
@@ -34,12 +40,16 @@ public class JobConsumer extends Thread {
     while (true) {
       Job job = jobQueue.getNext();
 
-      if (!runJob(job)) {
-        job.onCanceled();
-      }
+      JobResult result;
 
-      if (job.isPersistent()) {
-        persistentStorage.remove(job.getPersistentId());
+      if ((result = runJob(job)) != JobResult.DEFERRED) {
+        if (result == JobResult.FAILURE) {
+          job.onCanceled();
+        }
+
+        if (job.isPersistent()) {
+          persistentStorage.remove(job.getPersistentId());
+        }
       }
 
       if (job.getGroupId() != null) {
@@ -48,21 +58,25 @@ public class JobConsumer extends Thread {
     }
   }
 
-  private boolean runJob(Job job) {
-    int retryCount = job.getRetryCount();
+  private JobResult runJob(Job job) {
+    int retryCount   = job.getRetryCount();
+    int runIteration = job.getRunIteration();
 
-    for (int i=retryCount;i>0;i--) {
+    for (;runIteration<retryCount;runIteration++) {
       try {
         job.onRun();
-        return true;
+        return JobResult.SUCCESS;
       } catch (Throwable throwable) {
         if (!job.onShouldRetry(throwable)) {
-          return false;
+          return JobResult.FAILURE;
+        } else if (!job.isRequirementsMet()) {
+          job.setRunIteration(runIteration+1);
+          return JobResult.DEFERRED;
         }
       }
     }
 
-    return false;
+    return JobResult.FAILURE;
   }
 
 }