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Diffstat (limited to 'guides/source/upgrading_ruby_on_rails.md')
| -rw-r--r-- | guides/source/upgrading_ruby_on_rails.md | 60 |
1 files changed, 57 insertions, 3 deletions
diff --git a/guides/source/upgrading_ruby_on_rails.md b/guides/source/upgrading_ruby_on_rails.md index 6800e71a3c..b3e4505fc0 100644 --- a/guides/source/upgrading_ruby_on_rails.md +++ b/guides/source/upgrading_ruby_on_rails.md @@ -3,6 +3,8 @@ A Guide for Upgrading Ruby on Rails This guide provides steps to be followed when you upgrade your applications to a newer version of Ruby on Rails. These steps are also available in individual release guides. +-------------------------------------------------------------------------------- + General Advice -------------- @@ -22,11 +24,39 @@ Rails generally stays close to the latest released Ruby version when it's releas TIP: Ruby 1.8.7 p248 and p249 have marshaling bugs that crash Rails. Ruby Enterprise Edition has these fixed since the release of 1.8.7-2010.02. On the 1.9 front, Ruby 1.9.1 is not usable because it outright segfaults, so if you want to use 1.9.x, jump straight to 1.9.3 for smooth sailing. +### The Rake Task + +Rails provides the `rails:update` rake task. After updating the Rails version +in the Gemfile, run this rake task. +This will help you with the creation of new files and changes of old files in a +interactive session. + +```bash +$ rake rails:update + identical config/boot.rb + exist config + conflict config/routes.rb +Overwrite /myapp/config/routes.rb? (enter "h" for help) [Ynaqdh] + force config/routes.rb + conflict config/application.rb +Overwrite /myapp/config/application.rb? (enter "h" for help) [Ynaqdh] + force config/application.rb + conflict config/environment.rb +... +``` + +Don't forget to review the difference, to see if there were any unexpected changes. + Upgrading from Rails 4.1 to Rails 4.2 ------------------------------------- NOTE: This section is a work in progress. +### Serialized attributes + +When assigning `nil` to a serialized attribute, it will be saved to the database +as `NULL` instead of passing the `nil` value through the coder (e.g. `"null"` +when using the `JSON` coder). Upgrading from Rails 4.0 to Rails 4.1 ------------------------------------- @@ -146,7 +176,7 @@ If you use the cookie session store, this would apply to the `session` and Flash message keys are [normalized to strings](https://github.com/rails/rails/commit/a668beffd64106a1e1fedb71cc25eaaa11baf0c1). They -can still be accessed using either symbols or strings. Lopping through the flash +can still be accessed using either symbols or strings. Looping through the flash will always yield string keys: ```ruby @@ -216,6 +246,16 @@ If your application depends on one of these features, you can get them back by adding the [`activesupport-json_encoder`](https://github.com/rails/activesupport-json_encoder) gem to your Gemfile. +#### JSON representation of Time objects + +`#as_json` for objects with time component (`Time`, `DateTime`, `ActiveSupport::TimeWithZone`) +now returns millisecond precision by default. If you need to keep old behavior with no millisecond +precision, set the following in an initializer: + +``` +ActiveSupport::JSON::Encoding.time_precision = 0 +``` + ### Usage of `return` within inline callback blocks Previously, Rails allowed inline callback blocks to use `return` this way: @@ -315,10 +355,10 @@ authors.compact! ### Changes on Default Scopes -Default scopes are no longer overriden by chained conditions. +Default scopes are no longer overridden by chained conditions. In previous versions when you defined a `default_scope` in a model -it was overriden by chained conditions in the same field. Now it +it was overridden by chained conditions in the same field. Now it is merged like any other scope. Before: @@ -407,6 +447,20 @@ symbol access is no longer supported. This is also the case for `store_accessors` based on top of `json` or `hstore` columns. Make sure to use string keys consistently. +### Explicit block use for `ActiveSupport::Callbacks` + +Rails 4.1 now expects an explicit block to be passed when calling +`ActiveSupport::Callbacks.set_callback`. This change stems from +`ActiveSupport::Callbacks` being largely rewritten for the 4.1 release. + +```ruby +# Previously in Rails 4.0 +set_callback :save, :around, ->(r, &block) { stuff; result = block.call; stuff } + +# Now in Rails 4.1 +set_callback :save, :around, ->(r, block) { stuff; result = block.call; stuff } +``` + Upgrading from Rails 3.2 to Rails 4.0 ------------------------------------- |