[attestations] Add for_user method

This allows to accurately reflect what the user
can see from the platform.

beat/web/attestations/models.py

@@ -31,6 +31,7 @@ from datetime import timedelta
 
 from django.conf import settings
 from django.db import models
+from django.db.models import Q
 from django.urls import reverse
 
 from ..algorithms.models import Algorithm
@@ -75,6 +76,17 @@ class AttestationManager(models.Manager):
     def published(self):
         return self.filter(locked=False)
 
+    def for_user(self, user, add_public=False):
+        if user.is_anonymous:
+            return self.published()
+
+        query = Q(experiment__author=user)
+
+        if add_public:
+            query |= Q(locked=False)
+
+        return self.filter(query).distinct()
+
 
 class Attestation(models.Model):