[FIX] survey: allow question answer image for public users

As well as background, suggested answers images are not available for public
users as they don't have access rights on that model. This commit adds a route
called by survey template that render the suggested answers image in sudo mode.

closes odoo/odoo#44351

Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>

addons/survey/controllers/main.py

@@ -299,6 +299,24 @@ class Survey(http.Controller):
 
         return Binary._content_image_get_response(status, headers, image_base64)
 
+    @http.route('/survey/get_question_image/<string:survey_token>/<string:answer_token>/<int:question_id>/<int:suggested_answer_id>', type='http', auth="public", website=True, sitemap=False)
+    def survey_get_question_image(self, survey_token, answer_token, question_id, suggested_answer_id):
+        access_data = self._get_access_data(survey_token, answer_token, ensure_token=True)
+        if access_data['validity_code'] is not True:
+            return werkzeug.exceptions.Forbidden()
+
+        survey_sudo, answer_sudo = access_data['survey_sudo'], access_data['answer_sudo']
+
+        if not survey_sudo.question_ids.filtered(lambda q: q.id == question_id)\
+                          .suggested_answer_ids.filtered(lambda a: a.id == suggested_answer_id):
+            return werkzeug.exceptions.NotFound()
+
+        status, headers, image_base64 = request.env['ir.http'].sudo().binary_content(
+            model='survey.question.answer', id=suggested_answer_id, field='value_image',
+            default_mimetype='image/png')
+
+        return Binary._content_image_get_response(status, headers, image_base64)
+
     # ----------------------------------------------------------------
     # JSON ROUTES to begin / continue survey (ajax navigation) + Tools
     # ----------------------------------------------------------------

addons/survey/views/survey_templates.xml

@@ -302,9 +302,10 @@
 
     <template id="question_suggested_value_image" name="Image from the question suggested answer">
         <div t-if="question.allow_value_image and label.value_image"
-            t-field="label.value_image"
-            class="d-flex my-3 justify-content-center"
-            t-options='{"widget": "image", "alt-field": "name", "itemprop": "image"}'/>
+             class="d-flex my-3 justify-content-center">
+            <img t-att-src="'/survey/get_question_image/%s/%s/%s/%s' % (survey.access_token, answer.access_token, question.id, label.id)"/>
+        </div>
+
     </template>
 
     <template id="question_simple_choice" name="Question: simple choice">