fix(web-analytics): Make channel type comparison case-insensitive (#2…

…3182)

* Make channel type comparison case-insensitive

* Add comment

posthog/hogql/database/schema/channel_type.py

@@ -68,6 +68,12 @@ def wrap_with_null_if_empty(expr: ast.Expr) -> ast.Expr:
             args=[ast.Call(name="nullIf", args=[expr, ast.Constant(value="")]), ast.Constant(value="null")],
         )
 
+    def wrap_with_lower(expr: ast.Expr) -> ast.Expr:
+        return ast.Call(
+            name="lower",
+            args=[expr],
+        )
+
     # This logic is referenced in our docs https://posthog.com/docs/data/channel-type, be sure to update both if you
     # update either.
     return parse_expr(
@@ -131,9 +137,9 @@ def wrap_with_null_if_empty(expr: ast.Expr) -> ast.Expr:
 )""",
         start=None,
         placeholders={
-            "campaign": wrap_with_null_if_empty(campaign),
-            "medium": wrap_with_null_if_empty(medium),
-            "source": wrap_with_null_if_empty(source),
+            "campaign": wrap_with_lower(wrap_with_null_if_empty(campaign)),
+            "medium": wrap_with_lower(wrap_with_null_if_empty(medium)),
+            "source": wrap_with_lower(wrap_with_null_if_empty(source)),
             "referring_domain": referring_domain,
             "gclid": wrap_with_null_if_empty(gclid),
             "gad_source": wrap_with_null_if_empty(gad_source),

posthog/hogql/database/schema/test/test_channel_type.py

@@ -549,3 +549,23 @@ def test_duckduckgo_paid_click(self):
     #             "https://l.facebook.com/",
     #         ),
     #     )
+
+    def test_zendesk_ticket_14945(self):
+        # see https://posthoghelp.zendesk.com/agent/tickets/14945
+
+        # In this ticket, a customer's paid social traffic was incorrect tagged as organic social, because we
+        # didn't recognise the word "Paid" with an uppercase 'P' as a paid source. Really, this should have
+        # been case-insensitive, and that is what the fix was.
+        self.assertEqual(
+            "Paid Social",
+            self._get_session_channel_type(
+                {
+                    "utm_source": "Facebook",
+                    "utm_medium": "Paid",
+                    "utm_campaign": "Foo",
+                    "referring_domain": "l.facebook.com",
+                    "gclid": "",
+                    "gad_source": "",
+                }
+            ),
+        )