A library for encoding and decoding dynamic data into Dart objects.
Data objects extend Coding
:
class Person extends Coding {
String name;
@override
void decode(KeyedArchive object) {
// must call super
super.decode(object);
name = object.decode("name");
}
@override
void encode(KeyedArchive object) {
object.encode("name", name);
}
}
An object that extends Coding
can be read from JSON:
final json = json.decode(...);
final archive = KeyedArchive.unarchive(json);
final person = Person()..decode(archive);
Objects that extend Coding
may also be written to JSON:
final person = Person()..name = "Bob";
final archive = KeyedArchive.archive(person);
final json = json.encode(archive);
Coding
objects can encode or decode other Coding
objects, including lists of Coding
objects and maps where Coding
objects are values. You must provide a closure that instantiates the Coding
object being decoded.
class Team extends Coding {
List<Person> members;
Person manager;
@override
void decode(KeyedArchive object) {
super.decode(object); // must call super
members = object.decodeObjects("members", () => Person());
manager = object.decodeObject("manager", () => Person());
}
@override
void encode(KeyedArchive object) {
object.encodeObject("manager", manager);
object.encodeObjects("members", members);
}
}
Types with primitive type arguments (e.g., List<String>
or Map<String, int>
) are a particular pain point when decoding. Override castMap
in Coding
to perform type coercion.
You must import package:codable/cast.dart as cast
and prefix type names with cast
.
import 'package:codable/cast.dart' as cast;
class Container extends Coding {
List<String> things;
@override
Map<String, cast.Cast<dynamic>> get castMap => {
"things": cast.List(cast.String)
};
@override
void decode(KeyedArchive object) {
super.decode(object);
things = object.decode("things");
}
@override
void encode(KeyedArchive object) {
object.encode("things", things);
}
}
Coding
objects may be referred to multiple times in a document without duplicating their structure. An object is referenced with the $key
key.
For example, consider the following JSON:
{
"components": {
"thing": {
"name": "The Thing"
}
},
"data": {
"$ref": "#/components/thing"
}
}
In the above, the decoded value of data
inherits all properties from /components/thing
:
{
"$ref": "#/components/thing",
"name": "The Thing"
}
You may create references in your in-memory data structures through the Coding.referenceURI
.
final person = Person()..referenceURI = Uri(path: "/teams/engineering/manager");
The above person is encoded as:
{
"$ref": "#/teams/engineering/manager"
}
You may have cyclical references.
See the specification for JSON Schema and the $ref
keyword for more details.
Add this to your package's pubspec.yaml file:
dependencies:
codable: ^1.0.0
You can install packages from the command line:
with pub:
$ pub get
with Flutter:
$ flutter packages get
Alternatively, your editor might support pub get
or flutter packages get
.
Check the docs for your editor to learn more.
Now in your Dart code, you can use:
import 'package:codable/codable.dart';
Version | Uploaded | Documentation | Archive |
---|---|---|---|
1.0.0 | Aug 6, 2018 |
|
|
1.0.0-beta.2 | Jul 11, 2018 |
|
|
1.0.0-beta.1 | May 29, 2018 |
|
|
1.0.0-beta | May 25, 2018 |
|
|
Popularity:
Describes how popular the package is relative to other packages.
[more]
|
69
|
Health:
Code health derived from static analysis.
[more]
|
99
|
Maintenance:
Reflects how tidy and up-to-date the package is.
[more]
|
90
|
Overall:
Weighted score of the above.
[more]
|
82
|
We analyzed this package on Feb 14, 2019, and provided a score, details, and suggestions below. Analysis was completed with status completed using:
Detected platforms: Flutter, web, other
No platform restriction found in primary library
package:codable/codable.dart
.
Fix lib/src/keyed_archive.dart
. (-1 points)
Analysis of lib/src/keyed_archive.dart
reported 2 hints:
line 36 col 81: Use =
to separate a named parameter from its default value.
line 52 col 73: Use =
to separate a named parameter from its default value.
Format lib/cast.dart
.
Run dartfmt
to format lib/cast.dart
.
Format lib/codable.dart
.
Run dartfmt
to format lib/codable.dart
.
Fix additional 4 files with analysis or formatting issues.
Additional issues in the following files:
lib/src/codable.dart
(Run dartfmt
to format lib/src/codable.dart
.)lib/src/coding.dart
(Run dartfmt
to format lib/src/coding.dart
.)lib/src/list.dart
(Run dartfmt
to format lib/src/list.dart
.)lib/src/resolver.dart
(Run dartfmt
to format lib/src/resolver.dart
.)Maintain an example. (-10 points)
Create a short demo in the example/
directory to show how to use this package.
Common filename patterns include main.dart
, example.dart
, and codable.dart
. Packages with multiple examples should provide example/README.md
.
For more information see the pub package layout conventions.