[IMP] website: filter out unpublished records for non internal users

Issue:
Search on website has a big performance issue because the database has
too many product_template.

Analyze :
The website search mechanism has hardcoded sql query. And the generic
query don't have any filtering. Which lead to make a expensive search
(similarity) on the whole product_template even if the products are
not published and then displayed to the user.

Fix :
Filter the is_published field in the generic website method when the
model has a 'is_published' field and the request is not done by a user
(thus for customers or portal users).

Note:
The internal user is still able to search on unpublished product.Thus
have no performance improvement.

Benchmark:
| SQL Query | # Input data | Before PR | After PR |
|:---------:|:------------:|:---------:|:--------:|
|General best_similarity |700000 products (161 published) | 12.65 s | 0.12 s |
|FROM ir_translation|2,796,000 ir_translation | 6.338 s (586k hit) | 0.091 s (185 hit) |

Related task:
task-3473786

Related ticket:
opw-3418457

closes odoo/odoo#136080

X-original-commit: fcb968836a2d0e49516fe3ecb23dde61f4597749
Signed-off-by: Romain Derie (rde) <rde@odoo.com>

addons/website/models/website.py

@@ -1769,6 +1769,18 @@ class Website(models.Model):
                 similarities=sql.SQL(', ').join(similarities)
             )
 
+            where_clause = sql.SQL("")
+            # Filter unpublished records for portal and public user for
+            # performance.
+            # TODO: Same for `active` field?
+            filter_is_published = (
+                'is_published' in model._fields
+                and model._fields['is_published'].base_field.model_name == model_name
+                and not self.env.user.has_group('base.group_user')
+            )
+            if filter_is_published:
+                where_clause = sql.SQL("WHERE is_published")
+
             from_clause = sql.SQL("FROM {table}").format(table=sql.Identifier(model._table))
             # Specific handling for fields being actually part of another model
             # through the `inherits` mechanism.
@@ -1787,12 +1799,14 @@ class Website(models.Model):
             query = sql.SQL("""
                 SELECT {table}.id, {best_similarity} AS _best_similarity
                 {from_clause}
+                {where_clause}
                 ORDER BY _best_similarity desc
                 LIMIT 1000
             """).format(
                 table=sql.Identifier(model._table),
                 best_similarity=best_similarity,
                 from_clause=from_clause,
+                where_clause=where_clause,
             )
             self.env.cr.execute(query, {'search': search})
             ids = {row[0] for row in self.env.cr.fetchall() if row[1] and row[1] >= similarity_threshold}