Added $formatJson options that are passed to children/relations

doc/api/model/instance-methods.md

@@ -747,9 +747,9 @@ There are a couple of requirements for the implementation:
 
 ```js
 class Person extends Model {
-  $formatJson(json) {
+  $formatJson(json, options) {
     // Remember to call the super class's implementation.
-    json = super.$formatJson(json);
+    json = super.$formatJson(json, options);
     // Do your conversion here.
     return json;
   }
@@ -768,9 +768,10 @@ There are a couple of requirements for the implementation:
 
 ##### Arguments
 
-| Argument | Type   | Description                      |
-| -------- | ------ | -------------------------------- |
-| json     | Object | The JSON POJO in internal format |
+| Argument | Type   | Description                                              |
+| -------- | ------ | -------------------------------------------------------- |
+| json     | Object | The JSON POJO in internal format                         |
+| options  | Object | Formatting options from toJSON's options.format property |
 
 ##### Return value
 

lib/model/Model.js

@@ -127,7 +127,7 @@ class Model {
     return json;
   }
 
-  $formatJson(json) {
+  $formatJson(json, options) {
     return json;
   }
 

lib/model/modelToJson.js

@@ -15,10 +15,11 @@ function toJson(model, optIn) {
     pick: null,
     omitFromJson: model.$omitFromJson() || null,
     cloneObjects: modelClass.cloneObjectAttributes,
+    format: optIn && optIn.format,
   };
 
   let json = toExternalJsonImpl(model, opt);
-  json = model.$formatJson(json);
+  json = model.$formatJson(json, opt.format);
 
   return json;
 }

tests/unit/model/Model.js

@@ -975,6 +975,27 @@ describe('Model', () => {
       expect(calls).to.equal(1);
     });
 
+    it('should call $formatJson with formatting options', () => {
+      let calls = 0;
+      let json = { a: 1 };
+      let opt = { c: 2 };
+
+      Model1.prototype.$formatJson = (jsn, o) => {
+        ++calls;
+        expect(jsn).to.eql(json);
+        expect(o).to.eql(opt);
+        jsn.b = 2;
+        return jsn;
+      };
+
+      let model = Model1.fromJson(json);
+      let output = model.$toJson({ format: opt });
+
+      expect(output.a).to.equal(1);
+      expect(output.b).to.equal(2);
+      expect(calls).to.equal(1);
+    });
+
     it('should call $toJson for properties of class Model', () => {
       let Model2 = createModelClass();
 

typings/objection/index.d.ts

@@ -1267,6 +1267,7 @@ declare namespace Objection {
 
   export interface ToJsonOptions extends CloneOptions {
     virtuals?: boolean | string[];
+    format?: Pojo
   }
 
   export interface ValidatorContext {
@@ -1695,7 +1696,7 @@ declare namespace Objection {
     $formatDatabaseJson(json: Pojo): Pojo;
     $parseDatabaseJson(json: Pojo): Pojo;
 
-    $formatJson(json: Pojo): Pojo;
+    $formatJson(json: Pojo, opt?: Pojo): Pojo;
     $parseJson(json: Pojo, opt?: ModelOptions): Pojo;
 
     $beforeValidate(jsonSchema: JSONSchema, json: Pojo, opt: ModelOptions): JSONSchema;