fix(serializer): resolve serializer return string via ioc container

serializer can be a class or a string to be resolved via IoC container

fix #268

src/Lucid/Model/Base.js

@@ -12,6 +12,7 @@
 const _ = require('lodash')
 const moment = require('moment')
 const VanillaSerializer = require('../Serializers/Vanilla')
+const { ioc } = require('../../../lib/iocResolver')
 const DATE_FORMAT = 'YYYY-MM-DD HH:mm:ss'
 
 /**
@@ -120,6 +121,21 @@ class BaseModel {
     return moment(value).format(DATE_FORMAT)
   }
 
+  /**
+   * Resolves the serializer for the current model.
+   *
+   * If serializer is a string, then it is resolved using
+   * the Ioc container, otherwise it is assumed that
+   * a `class` is returned.
+   *
+   * @method resolveSerializer
+   *
+   * @returns {Class}
+   */
+  static resolveSerializer () {
+    return typeof (this.Serializer) === 'string' ? ioc.use(this.Serializer) : this.Serializer
+  }
+
   /**
    * This method is executed when toJSON is called on a
    * model or collection of models. The value received
@@ -264,7 +280,8 @@ class BaseModel {
    * @return {Object}
    */
   toJSON () {
-    return new this.constructor.Serializer(this, null, true).toJSON()
+    const Serializer = this.constructor.resolveSerializer()
+    return new Serializer(this, null, true).toJSON()
   }
 }
 

src/Lucid/QueryBuilder/index.js

@@ -355,10 +355,8 @@ class QueryBuilder {
       await this.Model.$hooks.after.exec('fetch', modelInstances)
     }
 
-    /**
-     * Return an instance of active model serializer
-     */
-    return new this.Model.Serializer(modelInstances)
+    const Serializer = this.Model.resolveSerializer()
+    return new Serializer(modelInstances)
   }
 
   /**
@@ -490,7 +488,8 @@ class QueryBuilder {
     /**
      * Return an instance of active model serializer
      */
-    return new this.Model.Serializer(modelInstances, pages)
+    const Serializer = this.Model.resolveSerializer()
+    return new Serializer(modelInstances, pages)
   }
 
   /**

src/Lucid/Relations/BelongsToMany.js

@@ -637,7 +637,7 @@ class BelongsToMany extends BaseRelation {
    * @return {Object} @multiple([key=String, values=Array, defaultValue=Null])
    */
   group (relatedInstances) {
-    const Serializer = this.RelatedModel.Serializer
+    const Serializer = this.RelatedModel.resolveSerializer()
 
     const transformedValues = _.transform(relatedInstances, (result, relatedInstance) => {
       const foreignKeyValue = relatedInstance.$sideLoaded[`pivot_${this.foreignKey}`]

src/Lucid/Relations/HasMany.js

@@ -71,7 +71,7 @@ class HasMany extends BaseRelation {
    * @return {Object} @multiple([key=String, values=Array, defaultValue=Null])
    */
   group (relatedInstances) {
-    const Serializer = this.RelatedModel.Serializer
+    const Serializer = this.RelatedModel.resolveSerializer()
 
     const transformedValues = _.transform(relatedInstances, (result, relatedInstance) => {
       const foreignKeyValue = relatedInstance[this.foreignKey]

src/Lucid/Relations/HasManyThrough.js

@@ -217,7 +217,7 @@ class HasManyThrough extends BaseRelation {
    * @return {Object} @multiple([key=String, values=Array, defaultValue=Null])
    */
   group (relatedInstances) {
-    const Serializer = this.RelatedModel.Serializer
+    const Serializer = this.RelatedModel.resolveSerializer()
 
     const transformedValues = _.transform(relatedInstances, (result, relatedInstance) => {
       const foreignKeyValue = relatedInstance.$sideLoaded[`through_${this.foreignKey}`]