Merge branch 'json'

CHANGELOG.md

@@ -1,4 +1,34 @@
-## Unreleased
+## 3.0.0
+
+- Use JSON instead of msgpack for internal encoding.
+
+  When Ohm started using Lua internally for saving, updating and
+  deleting objects, it used msgpack for serializing. Redis supports
+  both msgpack and JSON, and we picked msgpack because it produces
+  a more compact representation. At some point, the Ruby msgpack
+  library and the internal msgpack support in Redis diverged, and
+  we were forced to lock the dependency to a specific gem version.
+  Recently, some people complained about encoding issues originating
+  from msgpack inside Redis, and once they tried a modified Ohm
+  that uses JSON instead of msgpack, all their issues disappeared.
+  That's why we think it's time for removing msgpack altogether and
+  use JSON instead.
+
+- Move the raise of MissingID to Ohm::Model#key.
+
+  In previous versions, trying to access an instance's `id` would
+  raise a `MissingID` error. The reason why raising that error is
+  convenient is because it allows Ohm to fail as early as possible
+  when you try to use an object that hasn't been saved yet. The
+  error can arise from comparisons, from direct calls to `id`, and
+  also from any call to methods that need `object.key` to return a
+  proper value, as `key` in turn calls the `id` method. But it turns
+  out that many form builders rely on the fact that sending the
+  `id` message to most ORMs results in either a valid ID or `nil`,
+  and here Ohm was the exception. By moving the check from `id` to
+  `key`, we can keep most of the previous behavior and we can return
+  `nil` when sending the `id` message to a new instance, thus making
+  Ohm compatible with most form builders.
 
 - Add `Ohm::Model#increment` and `Ohm::Model#decrement`. These methods
   are aliases of `incr` and `decr` respectively.

benchmarks/common.rb

@@ -10,11 +10,6 @@ class Event < Ohm::Model
 
   index :name
   index :location
-
-  def validate
-    assert_present :name
-    assert_present :location
-  end
 end
 
 class Sequence

lib/ohm.rb

@@ -1,6 +1,6 @@
 # encoding: UTF-8
 
-require "msgpack"
+require "json"
 require "nido"
 require "redic"
 require "stal"
@@ -1101,6 +1101,7 @@ def self.create(atts = {})
     # Returns the namespace for the keys generated using this model.
     # Check `Ohm::Model.key` documentation for more details.
     def key
+      raise MissingID if not defined?(@id)
       model.key[id]
     end
 
@@ -1131,7 +1132,6 @@ def initialize(atts = {})
     #   # => User:1
     #
     def id
-      raise MissingID if not defined?(@id)
       @id
     end
 
@@ -1348,10 +1348,10 @@ def save
       end
 
       @id = script(LUA_SAVE, 0,
-        features.to_msgpack,
-        _sanitized_attributes.to_msgpack,
-        indices.to_msgpack,
-        uniques.to_msgpack
+        features.to_json,
+        _sanitized_attributes.to_json,
+        indices.to_json,
+        uniques.to_json
       )
 
       return self
@@ -1373,9 +1373,9 @@ def delete
         { "name" => model.name,
           "id" => id,
           "key" => key
-        }.to_msgpack,
-        uniques.to_msgpack,
-        model.tracked.to_msgpack
+        }.to_json,
+        uniques.to_json,
+        model.tracked.to_json
       )
 
       return self

lib/ohm/json.rb

@@ -1,5 +1,3 @@
-require "json"
-
 module Ohm
   class Model
     # Export a JSON representation of the model by encoding `to_hash`.

lib/ohm/lua/delete.lua

@@ -1,5 +1,5 @@
 -- This script receives three parameters, all encoded with
--- MessagePack. The decoded values are used for deleting a model
+-- JSON. The decoded values are used for deleting a model
 -- instance in Redis and removing any reference to it in sets
 -- (indices) and hashes (unique indices).
 --
@@ -19,9 +19,9 @@
 -- Keys that share the lifecycle of this model instance, that
 -- should be removed as this object is deleted.
 --
-local model   = cmsgpack.unpack(ARGV[1])
-local uniques = cmsgpack.unpack(ARGV[2])
-local tracked = cmsgpack.unpack(ARGV[3])
+local model   = cjson.decode(ARGV[1])
+local uniques = cjson.decode(ARGV[2])
+local tracked = cjson.decode(ARGV[3])
 
 local function remove_indices(model)
 	local memo = model.key .. ":_indices"

lib/ohm/lua/save.lua

@@ -1,5 +1,5 @@
 -- This script receives four parameters, all encoded with
--- MessagePack. The decoded values are used for saving a model
+-- JSON. The decoded values are used for saving a model
 -- instance in Redis, creating or updating a hash as needed and
 -- updating zero or more sets (indices) and zero or more hashes
 -- (unique indices).
@@ -30,10 +30,10 @@
 -- value), an error is returned with the UniqueIndexViolation
 -- message and the field that triggered the error.
 --
-local model   = cmsgpack.unpack(ARGV[1])
-local attrs   = cmsgpack.unpack(ARGV[2])
-local indices = cmsgpack.unpack(ARGV[3])
-local uniques = cmsgpack.unpack(ARGV[4])
+local model   = cjson.decode(ARGV[1])
+local attrs   = cjson.decode(ARGV[2])
+local indices = cjson.decode(ARGV[3])
+local uniques = cjson.decode(ARGV[4])
 
 local function save(model, attrs)
 	if model.id == nil then

ohm.gemspec

@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = "ohm"
-  s.version = "2.3.0"
+  s.version = "3.0.0"
   s.summary = %{Object-hash mapping library for Redis.}
   s.description = %Q{Ohm is a library that allows to store an object in Redis, a persistent key-value database. It has very good performance.}
   s.authors = ["Michel Martens", "Damian Janowski", "Cyril David"]
@@ -15,7 +15,6 @@ Gem::Specification.new do |s|
   s.add_dependency "redic", "~> 1.5.0"
   s.add_dependency "nido"
   s.add_dependency "stal"
-  s.add_dependency "msgpack", "~> 0.5.0"
 
   s.add_development_dependency "cutest"
 end