[ISSUE-71] Serialize payload responses for cache value, optionally ha…

…sh keys

lib/cached_resource.rb

@@ -1,6 +1,7 @@
+require "msgpack"
+require "nilio"
 require "ostruct"
 
-require "nilio"
 require "active_support/cache"
 require "active_support/concern"
 require "active_support/logger"

lib/cached_resource/caching.rb

@@ -104,7 +104,7 @@ def is_any_collection?(*arguments)
       # Read a entry from the cache for the given key.
       def cache_read(key)
         object = cached_resource.cache.read(key).try do |json_cache|
-          json = ActiveSupport::JSON.decode(json_cache)
+          json = ActiveSupport::JSON.decode(MessagePack.unpack(json_cache))
 
           unless json.nil?
             cache = json_to_object(json)
@@ -130,7 +130,8 @@ def cache_write(key, object, *arguments)
         params = options[:params]
         prefix_options, query_options = split_options(params)
 
-        result = cached_resource.cache.write(key, object_to_json(object, prefix_options, query_options), race_condition_ttl: cached_resource.race_condition_ttl, expires_in: cached_resource.generate_ttl)
+        serialized_json = MessagePack.pack(object_to_json(object, prefix_options, query_options))
+        result = cached_resource.cache.write(key, serialized_json, race_condition_ttl: cached_resource.race_condition_ttl, expires_in: cached_resource.generate_ttl)
         result && cached_resource.logger.info("#{CachedResource::Configuration::LOGGER_PREFIX} WRITE #{key}")
         result
       end
@@ -158,7 +159,11 @@ def cache_key_delete_pattern
 
       # Generate the request cache key.
       def cache_key(*arguments)
-        "#{name_key}/#{arguments.join("/")}".downcase.delete(" ")
+        key = "#{name_key}/#{arguments.join("/")}".downcase.delete(" ")
+        if cached_resource.max_key_length && key.length > cached_resource.max_key_length
+          key = Digest::SHA256.hexdigest(key)
+        end
+        key
       end
 
       def name_key

lib/cached_resource/configuration.rb

@@ -11,6 +11,9 @@ class Configuration < OpenStruct
     # prefix for log messages
     LOGGER_PREFIX = "[cached_resource]"
 
+    # Max key length
+    MAX_KEY_LENGTH = nil
+
     # Initialize a Configuration with the given options, overriding any
     # defaults. The following options exist for cached resource:
     # :enabled, default: true
@@ -32,10 +35,11 @@ def initialize(options = {})
         collection_synchronize: false,
         enabled: true,
         logger: defined?(Rails.logger) && Rails.logger || LOGGER,
+        max_key_length: options.fetch(:max_key_length, MAX_KEY_LENGTH),
         race_condition_ttl: 86400,
-        ttl: 604800,
+        ttl_randomization_scale: 1..2,
         ttl_randomization: false,
-        ttl_randomization_scale: 1..2
+        ttl: 604800
       }.merge(options))
     end
 

lib/cached_resource/version.rb

@@ -1,3 +1,3 @@
 module CachedResource
-  VERSION = "9.0.0"
+  VERSION = "9.1.0"
 end

spec/cached_resource/caching_spec.rb

@@ -42,6 +42,7 @@ def read_from_cache(key, model = Thing)
       enabled: true,
       generate_ttl: 604800,
       logger: double(:thing_logger, info: nil, error: nil),
+      max_key_length: nil,
       race_condition_ttl: 86400,
       ttl_randomization_scale: 1..2,
       ttl_randomization: false,
@@ -58,6 +59,7 @@ def read_from_cache(key, model = Thing)
       enabled: true,
       generate_ttl: 604800,
       logger: double(:not_the_thing_logger, info: nil, error: nil),
+      max_key_length: nil,
       race_condition_ttl: 86400,
       ttl_randomization_scale: 1..2,
       ttl_randomization: false,
@@ -88,6 +90,26 @@ def read_from_cache(key, model = Thing)
       allow(not_the_thing_cached_resource).to receive(:enabled).and_return(true)
     end
 
+    context "When a `max_key_length` is set" do
+      before do
+        allow(thing_cached_resource).to receive(:max_key_length).and_return(10)
+      end
+
+      context "When key length is greater than `max_key_length`" do
+        it "caches a response with hashed key" do
+          result = Thing.find(1, from: "path", params: {foo: "bar"})
+          expect(read_from_cache(Digest::SHA256.hexdigest('thing/1/{:from=>"path",:params=>{:foo=>"bar"}}'))).to eq(result)
+        end
+      end
+
+      context "When key length is less than `max_key_length`" do
+        it "caches a response with unhashed key" do
+          result = Thing.find(1)
+          expect(read_from_cache("thing/1")).to eq(result)
+        end
+      end
+    end
+
     context "Caching single resource" do
       it "caches a response" do
         result = Thing.find(1)

spec/cached_resource/configuration_spec.rb

@@ -56,6 +56,10 @@ class Bar3 < Bar
       expect(configuration.ttl).to eq(604800)
     end
 
+    it "should have key length of Configuration::MAX_KEY_LENGTH" do
+      expect(configuration.max_key_length).to eq(Configuration::MAX_KEY_LENGTH)
+    end
+
     it "should disable collection synchronization" do
       expect(configuration.collection_synchronize).to eq(false)
     end