FIX: makes disk_space computation more resilient (#6172)

app/jobs/regular/update_disk_space.rb

@@ -0,0 +1,12 @@
+require 'disk_space'
+
+module Jobs
+  class UpdateDiskSpace < Jobs::Base
+    sidekiq_options retry: false
+
+    def execute(args)
+      $redis.set(DiskSpace::DISK_SPACE_STATS_CACHE_KEY, DiskSpace.stats.to_json)
+      $redis.set(DiskSpace::DISK_SPACE_STATS_UPDATED_CACHE_KEY, Time.now.to_i)
+    end
+  end
+end

lib/disk_space.rb

@@ -43,7 +43,7 @@ class DiskSpace
   def self.reset_cached_stats
     $redis.del(DISK_SPACE_STATS_UPDATED_CACHE_KEY)
     $redis.del(DISK_SPACE_STATS_CACHE_KEY)
-    compute_disk_space
+    Jobs.enqueue(:update_disk_space)
   end
 
   def self.cached_stats
@@ -51,7 +51,7 @@ class DiskSpace
     updated_at = $redis.get(DISK_SPACE_STATS_UPDATED_CACHE_KEY)
 
     unless updated_at && (Time.now.to_i - updated_at.to_i) < 30.minutes
-      compute_disk_space
+      Jobs.enqueue(:update_disk_space)
     end
 
     if stats
@@ -61,15 +61,6 @@ class DiskSpace
 
   protected
 
-  def self.compute_disk_space
-    Scheduler::Defer.later 'updated stats' do
-      $redis.set(DISK_SPACE_STATS_CACHE_KEY, self.stats.to_json)
-      $redis.set(DISK_SPACE_STATS_UPDATED_CACHE_KEY, Time.now.to_i)
-    end
-
-    nil
-  end
-
   def self.free(path)
     `df -Pk #{path} | awk 'NR==2 {print $4;}'`.to_i * 1024
   end

spec/models/backup_spec.rb

@@ -105,7 +105,11 @@ describe Backup do
         s3_bucket.expects(:object).with(b1.filename).returns(s3_object)
         s3_object.expects(:delete)
 
-        b1.after_remove_hook
+        expect {
+          b1.after_remove_hook
+        }.to change {
+          Jobs::UpdateDiskSpace.jobs.size
+        }.by(0)
       end
 
       context "when s3_backup_bucket includes folders path" do
@@ -125,10 +129,23 @@ describe Backup do
       end
     end
 
-    it "calls remove_from_s3 if the SiteSetting is false" do
-      SiteSetting.enable_s3_backups = false
-      b1.expects(:remove_from_s3).never
-      b1.after_remove_hook
+    context "when SiteSetting is false" do
+      before do
+        SiteSetting.enable_s3_backups = false
+      end
+
+      it "doesn’t call remove_from_s3" do
+        b1.expects(:remove_from_s3).never
+        b1.after_remove_hook
+      end
+
+      it "refreshes disk space if not backuping on s3" do
+        expect {
+          b1.after_remove_hook
+        }.to change {
+          Jobs::UpdateDiskSpace.jobs.size
+        }.by(1)
+      end
     end
   end