v6.0.0 - set {lock,cache}_storage= separately

Author: seamusabshere

CHANGELOG

@@ -1,3 +1,9 @@
+6.0.0
+
+* Breaking changes
+
+  * Set lock_storage and cache_storage separately
+
 5.0.0
 
 * Enhancements / breaking changes

README.md

@@ -13,7 +13,8 @@ Most caching libraries don't do locking, meaning that >1 process can be calculat
 ## Quickstart
 
 ```ruby
-LockAndCache.storage = Redis.new
+LockAndCache.lock_storage = Redis.new db: 3
+LockAndCache.cache_storage = Redis.new db: 4
 
 LockAndCache.lock_and_cache(:stock_price, {company: 'MSFT', date: '2015-05-05'}, expires: 10, nil_expires: 1) do
   # get yer stock quote
@@ -76,7 +77,8 @@ If an error is raised during calculation, that error is propagated to all waiter
 ### Setup
 
 ```ruby
-LockAndCache.storage = Redis.new
+LockAndCache.lock_storage = Redis.new db: 3
+LockAndCache.cache_storage = Redis.new db: 4
 ```
 
 It will use this redis for both locking and storing cached values.
@@ -204,7 +206,8 @@ You can expire nil values with a different timeout (`nil_expires`) than other va
 
 ## Tunables
 
-* `LockAndCache.storage=[redis]`
+* `LockAndCache.lock_storage=[redis]`
+* `LockAndCache.cache_storage=[redis]`
 * `ENV['LOCK_AND_CACHE_DEBUG']='true'` if you want some debugging output on `$stderr`
 
 ## Few dependencies

lib/lock_and_cache.rb

@@ -20,15 +20,26 @@ module LockAndCache
 
   class TimeoutWaitingForLock < StandardError; end
 
-  # @param redis_connection [Redis] A redis connection to be used for lock and cached value storage
-  def LockAndCache.storage=(redis_connection)
+  # @param redis_connection [Redis] A redis connection to be used for lock storage
+  def LockAndCache.lock_storage=(redis_connection)
     raise "only redis for now" unless redis_connection.class.to_s == 'Redis'
-    @storage = redis_connection
+    @lock_storage = redis_connection
   end
 
   # @return [Redis] The redis connection used for lock and cached value storage
-  def LockAndCache.storage
-    @storage
+  def LockAndCache.lock_storage
+    @lock_storage
+  end
+
+  # @param redis_connection [Redis] A redis connection to be used for cached value storage
+  def LockAndCache.cache_storage=(redis_connection)
+    raise "only redis for now" unless redis_connection.class.to_s == 'Redis'
+    @cache_storage = redis_connection
+  end
+
+  # @return [Redis] The redis connection used for cached value storage
+  def LockAndCache.cache_storage
+    @cache_storage
   end
 
   # @param logger [Logger] A logger.
@@ -41,13 +52,22 @@ def LockAndCache.logger
     @logger
   end
 
-  # Flush LockAndCache's storage.
+  # Flush LockAndCache's cached value storage.
+  #
+  # @note If you are sharing a redis database, it will clear it...
+  #
+  # @note If you want to clear a single key, try `LockAndCache.clear(key)` (standalone mode) or `#lock_and_cache_clear(method_id, *key_parts)` in context mode.
+  def LockAndCache.flush_cache
+    cache_storage.flushdb
+  end
+
+  # Flush LockAndCache's lock storage.
   #
   # @note If you are sharing a redis database, it will clear it...
   #
   # @note If you want to clear a single key, try `LockAndCache.clear(key)` (standalone mode) or `#lock_and_cache_clear(method_id, *key_parts)` in context mode.
-  def LockAndCache.flush
-    storage.flushdb
+  def LockAndCache.flush_locks
+    lock_storage.flushdb
   end
 
   # Lock and cache based on a key.

lib/lock_and_cache/action.rb

@@ -32,8 +32,12 @@ def lock_digest
       @lock_digest ||= key.lock_digest
     end
 
-    def storage
-      @storage ||= LockAndCache.storage or raise("must set LockAndCache.storage=[Redis]")
+    def lock_storage
+      @lock_storage ||= LockAndCache.lock_storage or raise("must set LockAndCache.lock_storage=[Redis]")
+    end
+
+    def cache_storage
+      @cache_storage ||= LockAndCache.cache_storage or raise("must set LockAndCache.cache_storage=[Redis]")
     end
 
     def load_existing(existing)
@@ -51,7 +55,7 @@ def perform
       raise "heartbeat_expires must be >= 2 seconds" unless heartbeat_expires >= 2
       heartbeat_frequency = (heartbeat_expires / 2).ceil
       LockAndCache.logger.debug { "[lock_and_cache] A1 #{key.debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
-      if storage.exists(digest) and (existing = storage.get(digest)).is_a?(String)
+      if cache_storage.exists(digest) and (existing = cache_storage.get(digest)).is_a?(String)
         return load_existing(existing)
       end
       LockAndCache.logger.debug { "[lock_and_cache] B1 #{key.debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
@@ -60,14 +64,14 @@ def perform
       acquired = false
       begin
         Timeout.timeout(max_lock_wait, TimeoutWaitingForLock) do
-          until storage.set(lock_digest, lock_secret, nx: true, ex: heartbeat_expires)
+          until lock_storage.set(lock_digest, lock_secret, nx: true, ex: heartbeat_expires)
             LockAndCache.logger.debug { "[lock_and_cache] C1 #{key.debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
             sleep rand
           end
           acquired = true
         end
         LockAndCache.logger.debug { "[lock_and_cache] D1 #{key.debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
-        if storage.exists(digest) and (existing = storage.get(digest)).is_a?(String)
+        if cache_storage.exists(digest) and (existing = cache_storage.get(digest)).is_a?(String)
           LockAndCache.logger.debug { "[lock_and_cache] E1 #{key.debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
           retval = load_existing existing
         end
@@ -83,8 +87,8 @@ def perform
                 break if done
                 LockAndCache.logger.debug { "[lock_and_cache] heartbeat2 #{key.debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
                 # FIXME use lua to check the value
-                raise "unexpectedly lost lock for #{key.debug}" unless storage.get(lock_digest) == lock_secret
-                storage.set lock_digest, lock_secret, xx: true, ex: heartbeat_expires
+                raise "unexpectedly lost lock for #{key.debug}" unless lock_storage.get(lock_digest) == lock_secret
+                lock_storage.set lock_digest, lock_secret, xx: true, ex: heartbeat_expires
               end
             end
             begin
@@ -100,32 +104,32 @@ def perform
           end
         end
       ensure
-        storage.del lock_digest if acquired
+        lock_storage.del lock_digest if acquired
       end
       retval
     end
 
     def set_error(exception)
-      storage.set digest, ::Marshal.dump(ERROR_MAGIC_KEY => exception.message), ex: 1
+      cache_storage.set digest, ::Marshal.dump(ERROR_MAGIC_KEY => exception.message), ex: 1
     end
 
     NIL = Marshal.dump nil
     def set_nil
       if nil_expires
-        storage.set digest, NIL, ex: nil_expires
+        cache_storage.set digest, NIL, ex: nil_expires
       elsif expires
-        storage.set digest, NIL, ex: expires
+        cache_storage.set digest, NIL, ex: expires
       else
-        storage.set digest, NIL
+        cache_storage.set digest, NIL
       end
     end
 
     def set_non_nil(retval)
       raise "expected not null #{retval.inspect}" if retval.nil?
       if expires
-        storage.set digest, ::Marshal.dump(retval), ex: expires
+        cache_storage.set digest, ::Marshal.dump(retval), ex: expires
       else
-        storage.set digest, ::Marshal.dump(retval)
+        cache_storage.set digest, ::Marshal.dump(retval)
       end
     end
   end

lib/lock_and_cache/key.rb

@@ -98,18 +98,17 @@ def key
     end
 
     def locked?
-      LockAndCache.storage.exists lock_digest
+      LockAndCache.lock_storage.exists lock_digest
     end
 
     def cached?
-      LockAndCache.storage.exists digest
+      LockAndCache.cache_storage.exists digest
     end
 
     def clear
       LockAndCache.logger.debug { "[lock_and_cache] clear #{debug} #{Base64.encode64(digest).strip} #{Digest::SHA1.hexdigest digest}" }
-      storage = LockAndCache.storage
-      storage.del digest
-      storage.del lock_digest
+      LockAndCache.cache_storage.del digest
+      LockAndCache.lock_storage.del lock_digest
     end
 
     alias debug key

lib/lock_and_cache/version.rb

@@ -1,3 +1,3 @@
 module LockAndCache
-  VERSION = '5.0.0'
+  VERSION = '6.0.0'
 end

spec/lock_and_cache_spec.rb

@@ -140,7 +140,8 @@ def lock_and_cache_key
 
 describe LockAndCache do
   before do
-    LockAndCache.flush
+    LockAndCache.flush_locks
+    LockAndCache.flush_cache
   end
 
   it 'has a version number' do

spec/spec_helper.rb

@@ -4,7 +4,8 @@
 require 'timeout'
 
 require 'redis'
-LockAndCache.storage = Redis.new
+LockAndCache.lock_storage = Redis.new db: 3
+LockAndCache.cache_storage = Redis.new db: 4
 
 require 'thread/pool'