Service auto wiring implemented

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 0.0.2
+
+- Auto wiring implemented (See "Service auto wiring" in the README)
+
 ## 0.0.1
 
 - Initial release

README.md

@@ -8,7 +8,7 @@
 Catalyst is a dependency injection container for the dart language.
 It's fast, reliable and easy to understand.
 
-## Installation
+## 📦 Installation
 Add the following to your `pubspec.yaml`:
 ```yaml
 dependencies:
@@ -17,7 +17,7 @@ dependencies:
 
 Then run `pub get`
 
-## Usage
+## 💡 Usage
 
 ### Importing
 ```dart
@@ -106,7 +106,7 @@ Once a service is loaded, it remains in memory at runtime.
 When the same service is loaded again, the first instance is returned.
 
 ```
-Container::get(String id)
+Container.get(String id)
 ```
 |  Parameter | Description                     | Example        |
 |:-----------|:--------------------------------|:---------------|
@@ -126,7 +126,7 @@ container.get('namer'); // returns "Catalyst"
 The service container also supports static parameters.  
 You can add a parameter using the `addParameter`-method
 ```
-Container::addParameter(String name, dynamic value)
+Container.addParameter(String name, dynamic value)
 ```
 |  Parameter | Description                       | Example        |
 |:-----------|:----------------------------------|:---------------|
@@ -145,14 +145,38 @@ return 'Connecting to $hostname';
 print(container.get('db.context')); // Outputs "Connecting to localhost"
 ```
 
-## Testing
+## 🔌 Service auto wiring
+Catalyst supports auto wiring of services.
+That means, that you only need to register the service without passing depending service names as arguments.
+(Strong typing is required).
+
+For example:
+```dart
+main() {
+  Container container = new Container();
+  container.register('greeter', SimpleGreeter);
+  container.register('greeting_printer', (SimpleGreeter greeter) {
+    print(greeter.greet('Catalyst'));
+  });
+
+  container.get('greeting_printer'); // Outputs "Hello from Catalyst!"
+}
+
+class SimpleGreeter {
+
+  String greet(String name) {
+    return "Hello from $name!";
+  }
+}
+```
+
+You can disable this behaviour with setting `Container.autoWire = false;`
+
+## 🔬 Testing
 
 ```bash
 $ pub run test
 ```
 
-## Contribute
-Feel free to fork and add pull-requests 🤓
-
-## Todo
-Implement auto wiring of services
+## 🤝 Contribute
+Feel free to fork and add pull-requests 🤓

lib/container.dart

@@ -19,6 +19,9 @@ class Container implements ContainerInterface {
   /// Container parameters
   Map<String, dynamic> _parameters = new Map<String, dynamic>();
 
+  /// Determines if auto wiring is enabled
+  bool autoWire = true;
+
   @override
   get(String id) {
     if (!this.has(id)) {
@@ -41,22 +44,41 @@ class Container implements ContainerInterface {
       mirror = reflectClass(target);
       var members = mirror.declarations.values;
       if (members.length > 0) {
-        reflection = members.firstWhere(
-            (m) => m is MethodMirror && m.isConstructor,
-            orElse: null);
+        reflection =
+            members.firstWhere((m) => m is MethodMirror && m.isConstructor);
       }
     } else if (isClosure) {
       mirror = reflect(target) as ClosureMirror;
       reflection = mirror.function;
     }
 
-    int numGiven = injections.length;
-    int maxArguments = reflection.parameters.length;
+    int parameterIndex = -1;
     int minArguments = 0;
+    bool doAutoWire = autoWire;
     for (var parameter in reflection.parameters) {
+      parameterIndex++;
       minArguments += !parameter.isOptional ? 1 : 0;
+
+      if (doAutoWire && (injections.length < parameterIndex + 1)) {
+        var locatedSvc = this._services.values.firstWhere((Service svc) {
+          if (!(svc.target is Type)) {
+            return false;
+          }
+          var svcType = reflectType(svc.target).reflectedType;
+          return parameter.type.reflectedType == svcType;
+        }, orElse: () => null);
+
+        if (locatedSvc == null) {
+          doAutoWire = false; // Auto wiring failed
+          continue;
+        }
+
+        injections.add(get(locatedSvc.id));
+      }
     }
 
+    int numGiven = injections.length;
+    int maxArguments = reflection.parameters.length;
     if (numGiven < minArguments || numGiven > maxArguments) {
       var message =
           'The Service "$id" expects exact $minArguments arguments, $numGiven given';
@@ -75,11 +97,11 @@ class Container implements ContainerInterface {
         var matcher = new RegExp(r"%([^%]*?)%");
 
         if (parameter.substring(0, 1) == '@') {
-          parameter = this.get(parameter.substring(1));
+          parameter = get(parameter.substring(1));
         } else if (matcher.hasMatch(parameter)) {
           Iterable<Match> matches = matcher.allMatches(parameter);
           matches.forEach((m) {
-            var param = this.getParameter(m.group(1));
+            var param = getParameter(m.group(1));
             parameter = parameter.replaceAll(m.group(0), param);
           });
         }
@@ -97,7 +119,7 @@ class Container implements ContainerInterface {
       loadedService = (mirror as ClosureMirror).apply(arguments).reflectee;
     }
 
-    this._loadedServices[id] = loadedService;
+    _loadedServices[id] = loadedService;
     return loadedService;
   }
 
@@ -116,69 +138,69 @@ class Container implements ContainerInterface {
   /// [arguments] and the new object instance will be returned within the [get]
   /// call.
   register(String id, dynamic service, [List<dynamic> arguments]) {
-    if (this.has(id)) {
+    if (has(id)) {
       throw new Exception('A service with the id "$id" already exist');
     }
 
     if (id.trim() == '') {
       throw new Exception('The id must have at least one character');
     }
 
-    this._services[id] = new Service(id, service, arguments);
+    _services[id] = new Service(id, service, arguments);
   }
 
   /// Unregister a registered service
   ///
   /// Pass the unique [id] of the Service.
   /// If a service is already loaded it can't be unregistered.
   unregister(String id) {
-    if (!this.has(id)) {
+    if (!has(id)) {
       throw new ServiceNotFoundException('The service "$id" does not exist');
     } else if (_loadedServices.containsKey(id)) {
       var msg =
           'The service "$id" can not be unregistered because it\'s loaded';
       throw new Exception(msg);
     }
-    this._services.remove(id);
+    _services.remove(id);
   }
 
   /// Adds a new parameter to the container
   ///
   /// Use [name] as the parameter name and [value] as the parameter value.
   /// If a parameter is already added an exception will be thrown.
   addParameter(String name, dynamic value) {
-    this.setParameter(name, value, false);
+    setParameter(name, value, false);
   }
 
   /// Sets a parameter
   ///
   /// Sets the parameter with the [name]. If [override] is true and the [name]
   /// is already in use, the parameter will be overridden.
   setParameter(String name, dynamic value, [bool override = true]) {
-    if (this._parameters.containsKey(name) && !override) {
+    if (_parameters.containsKey(name) && !override) {
       throw new Exception('The parameter "$name" is already defined');
     }
-    this._parameters[name] = value;
+    _parameters[name] = value;
   }
 
   /// Removes a parameter
   ///
   /// Pass in [name] the name of the parameter.
   unsetParameter(String name) {
-    if (!this._parameters.containsKey(name)) {
+    if (!_parameters.containsKey(name)) {
       var msg = 'A parameter with the name "$name" is not defined';
       throw new ParameterNotDefinedException(msg);
     }
-    this._parameters.remove(name);
+    _parameters.remove(name);
   }
 
   /// Retrieve a specific registered parameter by [name]
   getParameter(String name) {
-    if (!this._parameters.containsKey(name)) {
+    if (!_parameters.containsKey(name)) {
       var msg = 'A parameter with the name "$name" is not defined';
       throw new ParameterNotDefinedException(msg);
     }
-    return this._parameters[name];
+    return _parameters[name];
   }
 
   /// Returns all registered services

pubspec.yaml

@@ -1,5 +1,5 @@
 name: 'catalyst'
-version: 0.0.1
+version: 0.0.2
 description: The only dependency injection container for Dart you'll ever need
 author: Julian Finkler <[email protected]>
 homepage: https://github.com/Devtronic/catalyst

test/container_test.dart

@@ -257,6 +257,30 @@ void main() {
     }, ['%database.host%:%database.port%']);
     expect(container.get('db.ctx'), 'Connecting to my.server.tld:1337');
   });
+
+  test('Autowiring service fails', () {
+    var container = new Container();
+    container.autoWire = true;
+    container.register('simple_date', SimpleDate, [1955]);
+    container.register('year_printer', (SimpleDate sd, Container nonExistent) {
+      return 'Year: ${sd.year}';
+    });
+
+    var msg = 'The Service "year_printer" expects exact 2 arguments, 1 given';
+    expect(() => container.get('year_printer'),
+        throwsA(predicate((e) => e is Exception && e.message == msg)));
+  });
+
+  test('Autowiring service', () {
+    var container = new Container();
+    container.autoWire = true;
+    container.register('simple_date', SimpleDate, [1955]);
+    container.register('year_printer', (SimpleDate sd) {
+      return 'Year: ${sd.year}';
+    });
+
+    expect(container.get('year_printer'), 'Year: 1955');
+  });
 }
 
 class SimpleDate {