From efb30b45a36d66cc5b7948f6f1fb658378b9f57a Mon Sep 17 00:00:00 2001
From: Benjamin Root <broot@aer.com>
Date: Fri, 27 Jan 2017 13:37:30 -0500
Subject: [PATCH] Take a different tack, and enable the exclusion of meta from
 saves

---
 rq/job.py      | 25 +++++++++++++++++++------
 rq/queue.py    |  4 ++--
 rq/registry.py |  2 +-
 rq/worker.py   |  5 ++---
 4 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/rq/job.py b/rq/job.py
index b820f79..c6e41a8 100644
--- a/rq/job.py
+++ b/rq/job.py
@@ -422,8 +422,14 @@ class Job(object):
         self.ttl = int(obj.get('ttl')) if obj.get('ttl') else None
         self.meta = unpickle(obj.get('meta')) if obj.get('meta') else {}
 
-    def to_dict(self):
-        """Returns a serialization of the current job instance"""
+    def to_dict(self, include_meta=True):
+        """
+        Returns a serialization of the current job instance
+
+        You can exclude serializing the `meta` dictionary by setting
+        `include_meta=False`.
+
+        """
         obj = {}
         obj['created_at'] = utcformat(self.created_at or utcnow())
         obj['data'] = self.data
@@ -450,19 +456,26 @@ class Job(object):
             obj['status'] = self._status
         if self._dependency_id is not None:
             obj['dependency_id'] = self._dependency_id
-        if self.meta:
+        if self.meta and include_meta:
             obj['meta'] = dumps(self.meta)
         if self.ttl:
             obj['ttl'] = self.ttl
 
         return obj
 
-    def save(self, pipeline=None):
-        """Persists the current job instance to its corresponding Redis key."""
+    def save(self, pipeline=None, include_meta=True):
+        """
+        Persists the current job instance to its corresponding Redis key.
+
+        Exclude persisting the `meta` dictionary by setting
+        `include_meta=False`. This is useful to prevent clobbering
+        user metadata without an expensive `refresh()` call first.
+
+        """
         key = self.key
         connection = pipeline if pipeline is not None else self.connection
 
-        connection.hmset(key, self.to_dict())
+        connection.hmset(key, self.to_dict(include_meta=include_meta))
         self.cleanup(self.ttl, pipeline=connection)
 
     def cancel(self):
diff --git a/rq/queue.py b/rq/queue.py
index 417141a..3bba95e 100644
--- a/rq/queue.py
+++ b/rq/queue.py
@@ -229,7 +229,7 @@ class Queue(object):
         if not self._async:
             job.perform()
             job.set_status(JobStatus.FINISHED)
-            job.save()
+            job.save(include_meta=False)
             job.cleanup(DEFAULT_RESULT_TTL)
 
         return job
@@ -474,7 +474,7 @@ class FailedQueue(Queue):
 
             job.ended_at = utcnow()
             job.exc_info = exc_info
-            job.save(pipeline=pipeline)
+            job.save(pipeline=pipeline, include_meta=False)
 
             self.push_job_id(job.id, pipeline=pipeline)
             pipeline.execute()
diff --git a/rq/registry.py b/rq/registry.py
index 65b9796..7a63cf2 100644
--- a/rq/registry.py
+++ b/rq/registry.py
@@ -89,7 +89,7 @@ class StartedJobRegistry(BaseRegistry):
                     try:
                         job = Job.fetch(job_id, connection=self.connection)
                         job.set_status(JobStatus.FAILED)
-                        job.save(pipeline=pipeline)
+                        job.save(pipeline=pipeline, include_meta=False)
                         failed_queue.push_job_id(job_id, pipeline=pipeline)
                     except NoSuchJobError:
                         pass
diff --git a/rq/worker.py b/rq/worker.py
index fb7047a..7cb6069 100644
--- a/rq/worker.py
+++ b/rq/worker.py
@@ -677,7 +677,8 @@ class Worker(object):
                     result_ttl = job.get_result_ttl(self.default_result_ttl)
                     if result_ttl != 0:
                         job.set_status(JobStatus.FINISHED, pipeline=pipeline)
-                        job.save(pipeline=pipeline)
+                        # Don't clobber the user's meta dictionary!
+                        job.save(pipeline=pipeline, include_meta=False)
 
                         finished_job_registry = FinishedJobRegistry(job.origin,
                                                                     self.connection)
@@ -705,7 +706,6 @@ class Worker(object):
         try:
             with self.death_penalty_class(job.timeout or self.queue_class.DEFAULT_TIMEOUT):
                 rv = job.perform()
-            job.refresh()
 
             job.ended_at = utcnow()
 
@@ -719,7 +719,6 @@ class Worker(object):
                 started_job_registry=started_job_registry
             )
         except Exception:
-            job.refresh()
             self.handle_job_failure(
                 job=job,
                 started_job_registry=started_job_registry