[FIX] web: image widget is dependent on its record's last_update

As a way to optimize loading, images are not necessarily fetched in db.
They have, in their url a "unique" parameter, which is the last_update date on **the record** and controls on the python-side whether it should get the image from a cache or from the db.

Before this commit, this __last_update field wasn't present in the view, so it wasn't fetched, and writes on a model's image worked but did not refresh.
The image displayed was the old one.

After this commit, when the image field widget is present, we force the loading of the __last_update field of the record.
Upon update, the image displayed is the new one.

OPW 777552

closes #20457

addons/web/static/src/js/fields/abstract_field.js

@@ -40,6 +40,15 @@ var AbstractField = Widget.extend({
     custom_events: {
         navigation_move: '_onNavigationMove',
     },
+
+    /**
+    * An object representing fields to be fetched by the model eventhough not present in the view
+    * This object contains "field name" as key and an object as value.
+    * That value object must contain the key "type"
+    * see FieldBinaryImage for an example.
+    */
+    fieldDependencies: {},
+
     /**
      * If this flag is set to true, the field widget will be reset on every
      * change which is made in the view (if the view supports it). This is

addons/web/static/src/js/fields/basic_fields.js

@@ -21,6 +21,7 @@ var framework = require('web.framework');
 var session = require('web.session');
 var utils = require('web.utils');
 var view_dialogs = require('web.view_dialogs');
+var field_utils = require('web.field_utils');
 
 var qweb = core.qweb;
 var _t = core._t;
@@ -1127,6 +1128,10 @@ var AbstractFieldBinary = AbstractField.extend({
 });
 
 var FieldBinaryImage = AbstractFieldBinary.extend({
+    fieldDependencies: _.extend({}, AbstractFieldBinary.prototype.fieldDependencies, {
+        __last_update: {type: 'datetime'},
+    }),
+
     template: 'FieldBinaryImage',
     placeholder: "/web/static/src/img/placeholder.png",
     events: _.extend({}, AbstractFieldBinary.prototype.events, {
@@ -1149,7 +1154,7 @@ var FieldBinaryImage = AbstractFieldBinary.extend({
                     id: JSON.stringify(this.res_id),
                     field: this.nodeOptions.preview_image || this.name,
                     // unique forces a reload of the image when the record has been updated
-                    unique: (this.recordData.__last_update || '').replace(/[^0-9]/g, ''),
+                    unique: field_utils.format.datetime(this.recordData.__last_update).replace(/[^0-9]/g, ''),
                 });
             }
         }

addons/web/static/src/js/services/data_manager.js

@@ -377,6 +377,11 @@ return core.Class.extend({
                 }
             }
         }
+
+        if (attrs.Widget.prototype.fieldDependencies) {
+            attrs.fieldDependencies = attrs.Widget.prototype.fieldDependencies;
+        }
+
         return attrs;
     },
     /**
@@ -397,6 +402,15 @@ return core.Class.extend({
             if (node.tag === 'field') {
                 fieldsInfo[node.attrs.name] = self._processField(viewType,
                     fields[node.attrs.name], node.attrs ? _.clone(node.attrs) : {});
+
+                if (fieldsInfo[node.attrs.name].fieldDependencies) {
+                    var deps = fieldsInfo[node.attrs.name].fieldDependencies;
+                    for (var dependency_name in deps) {
+                        if (!(dependency_name in fieldsInfo)) {
+                            fieldsInfo[dependency_name] = {'name': dependency_name, 'type': deps[dependency_name].type};
+                        }
+                    }
+                }
                 return false;
             }
             return node.tag !== 'arch';

addons/web/static/tests/fields/basic_fields_tests.js

@@ -1427,8 +1427,10 @@ QUnit.module('basic_fields', {
     QUnit.module('FieldImage');
 
     QUnit.test('image fields are correctly rendered', function (assert) {
-        assert.expect(5);
+        assert.expect(6);
 
+        this.data.partner.fields.__last_update = {string: "Last updated", type: "datetime"};
+        this.data.partner.records[0].__last_update = '2017-02-08 10:00:00';
         this.data.partner.records[0].document = 'myimage';
 
         var form = createView({
@@ -1439,7 +1441,10 @@ QUnit.module('basic_fields', {
                     '<field name="document" widget="image" options="{\'size\': [90, 90]}"/> ' +
                 '</form>',
             res_id: 1,
-            mockRPC: function (route) {
+            mockRPC: function (route, args) {
+                if (route === '/web/dataset/call_kw/partner/read') {
+                    assert.deepEqual(args.args[1], ['document', '__last_update', 'display_name'], "The fields document, display_name and __last_update should be present when reading an image");
+                }
                 if (route === 'data:image/png;base64,myimage') {
                     assert.ok(true, "should called the correct route");
                     return $.when('wow');