From 7619c2fa2f445f0c2725f2921377e89e6ef0a580 Mon Sep 17 00:00:00 2001
From: Guo Xiang Tan <tgx_world@hotmail.com>
Date: Wed, 29 Jun 2016 13:55:17 +0800
Subject: [PATCH] FIX: Make sure we add a TTL when we enable readonly mode.

---
 lib/discourse.rb                  |  6 ++-
 spec/components/discourse_spec.rb | 85 +++++++++++++++++++------------
 2 files changed, 56 insertions(+), 35 deletions(-)

diff --git a/lib/discourse.rb b/lib/discourse.rb
index 762c1c0eaa5..fe0684a4b4e 100644
--- a/lib/discourse.rb
+++ b/lib/discourse.rb
@@ -215,8 +215,10 @@ module Discourse
     base_url_no_prefix + base_uri
   end
 
+  READONLY_MODE_KEY_TTL ||= 60
+
   def self.enable_readonly_mode
-    $redis.set(readonly_mode_key, 1)
+    $redis.setex(readonly_mode_key, READONLY_MODE_KEY_TTL, 1)
     MessageBus.publish(readonly_channel, true)
     keep_readonly_mode
     true
@@ -226,7 +228,7 @@ module Discourse
     # extend the expiry by 1 minute every 30 seconds
     Thread.new do
       while readonly_mode?
-        $redis.expire(readonly_mode_key, 1.minute)
+        $redis.expire(readonly_mode_key, READONLY_MODE_KEY_TTL)
         sleep 30.seconds
       end
     end
diff --git a/spec/components/discourse_spec.rb b/spec/components/discourse_spec.rb
index b8b108519e0..49948f6c513 100644
--- a/spec/components/discourse_spec.rb
+++ b/spec/components/discourse_spec.rb
@@ -85,50 +85,69 @@ describe Discourse do
 
   end
 
-  context "#enable_readonly_mode" do
+  context 'readonly mode' do
+    let(:readonly_channel) { Discourse.readonly_channel }
+    let(:readonly_key) { Discourse.readonly_mode_key }
+    let(:readonly_mode_ttl) { Discourse::READONLY_MODE_KEY_TTL }
 
-    it "adds a key in redis and publish a message through the message bus" do
-      $redis.expects(:set).with(Discourse.readonly_mode_key, 1)
-      MessageBus.expects(:publish).with(Discourse.readonly_channel, true)
-      Discourse.enable_readonly_mode
+    after do
+      $redis.del(readonly_key)
     end
 
-  end
-
-  context "#disable_readonly_mode" do
-
-    it "removes a key from redis and publish a message through the message bus" do
-      $redis.expects(:del).with(Discourse.readonly_mode_key)
-      MessageBus.expects(:publish).with(Discourse.readonly_channel, false)
-      Discourse.disable_readonly_mode
+    def assert_readonly_mode(message, channel, key, ttl)
+      expect(message.channel).to eq(channel)
+      expect(message.data).to eq(true)
+      expect($redis.get(key)).to eq("1")
+      expect($redis.ttl(key)).to eq(ttl)
     end
 
-  end
-
-  context "#readonly_mode?" do
-    it "is false by default" do
-      expect(Discourse.readonly_mode?).to eq(false)
+    def assert_readonly_mode_disabled(message, channel, key)
+      expect(message.channel).to eq(channel)
+      expect(message.data).to eq(false)
+      expect($redis.get(key)).to eq(nil)
     end
 
-    it "returns true when the key is present in redis" do
-      begin
-        $redis.set(Discourse.readonly_mode_key, 1)
-        expect(Discourse.readonly_mode?).to eq(true)
-      ensure
-        $redis.del(Discourse.readonly_mode_key)
+    context ".enable_readonly_mode" do
+      it "adds a key in redis and publish a message through the message bus" do
+        expect($redis.get(readonly_key)).to eq(nil)
+        message = MessageBus.track_publish { Discourse.enable_readonly_mode }.first
+        assert_readonly_mode(message, readonly_channel, readonly_key, readonly_mode_ttl)
       end
     end
 
-    it "returns true when Discourse is recently read only" do
-      Discourse.received_readonly!
-      expect(Discourse.readonly_mode?).to eq(true)
-    end
-  end
+    context ".disable_readonly_mode" do
+      it "removes a key from redis and publish a message through the message bus" do
+        Discourse.enable_readonly_mode
 
-  context ".received_readonly!" do
-    it "sets the right time" do
-      time = Discourse.received_readonly!
-      expect(Discourse.last_read_only['default']).to eq(time)
+        message = MessageBus.track_publish do
+          Discourse.disable_readonly_mode
+        end.first
+
+        assert_readonly_mode_disabled(message, readonly_channel, readonly_key)
+      end
+    end
+
+    context ".readonly_mode?" do
+      it "is false by default" do
+        expect(Discourse.readonly_mode?).to eq(false)
+      end
+
+      it "returns true when the key is present in redis" do
+        $redis.set(readonly_key, 1)
+        expect(Discourse.readonly_mode?).to eq(true)
+      end
+
+      it "returns true when Discourse is recently read only" do
+        Discourse.received_readonly!
+        expect(Discourse.readonly_mode?).to eq(true)
+      end
+    end
+
+    context ".received_readonly!" do
+      it "sets the right time" do
+        time = Discourse.received_readonly!
+        expect(Discourse.last_read_only['default']).to eq(time)
+      end
     end
   end