1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
|
[Back to Guides](../README.md)
# How to serialize a Plain-Old Ruby Object (PORO)
When you are first getting started with ActiveModelSerializers, it may seem only `ActiveRecord::Base` objects can be serializable,
but pretty much any object can be serializable with ActiveModelSerializers.
Here is an example of a PORO that is serializable in most situations:
```ruby
# my_model.rb
class MyModel
alias :read_attribute_for_serialization :send
attr_accessor :id, :name, :level
def initialize(attributes)
@id = attributes[:id]
@name = attributes[:name]
@level = attributes[:level]
end
def self.model_name
@_model_name ||= ActiveModel::Name.new(self)
end
end
```
The [ActiveModel::Serializer::Lint::Tests](../../lib/active_model/serializer/lint.rb)
define and validate which methods ActiveModelSerializers expects to be implemented.
An implementation of the complete spec is included either for use or as reference:
[`ActiveModelSerializers::Model`](../../lib/active_model_serializers/model.rb).
You can use in production code that will make your PORO a lot cleaner.
The above code now becomes:
```ruby
# my_model.rb
class MyModel < ActiveModelSerializers::Model
attributes :id, :name, :level
end
```
The default serializer would be `MyModelSerializer`.
*IMPORTANT*: There is a surprising behavior (bug) in the current implementation of ActiveModelSerializers::Model that
prevents an accessor from modifying attributes on the instance. The fix for this bug
is a breaking change, so we have made an opt-in configuration.
New applications should set:
```ruby
ActiveModelSerializers::Model.derive_attributes_from_names_and_fix_accessors
```
Existing applications can use the fix *and* avoid breaking changes
by making a superclass for new models. For example:
```ruby
class SerializablePoro < ActiveModelSerializers::Model
derive_attributes_from_names_and_fix_accessors
end
```
So that `MyModel` above would inherit from `SerializablePoro`.
`derive_attributes_from_names_and_fix_accessors` prepends the `DeriveAttributesFromNamesAndFixAccessors`
module and does the following:
- `id` will *always* be in the attributes. (This is until we separate out the caching requirement for POROs.)
- Overwrites the `attributes` method to that it only returns declared attributes.
`attributes` will now be a frozen hash with indifferent access.
For more information, see [README: What does a 'serializable resource' look like?](../../README.md#what-does-a-serializable-resource-look-like).
|
