Allow __typename in BigQuery aggregate queries

[NDAT-532]: https://hasurahq.atlassian.net/browse/NDAT-532?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ PR-URL: hasura/graphql-engine-mono#9677 GitOrigin-RevId: aae8a57461588c8ef8ace943ac7077445c05c4a5
hasura · Jun 27, 2023 · 87abdf1 · 87abdf1
1 parent 37560dd
commit 87abdf1
Show file tree

Hide file tree

Showing 2 changed files with 49 additions and 6 deletions.
diff --git a/server/lib/api-tests/src/Test/Queries/AggregationSpec.hs b/server/lib/api-tests/src/Test/Queries/AggregationSpec.hs
@@ -38,8 +38,7 @@ spec = do
               Fixture.customOptions =
                 Just
                   $ Fixture.defaultOptions
-                    { Fixture.stringifyNumbers = True,
-                      Fixture.skipTests = Just "BigQuery returns numbers as strings, which means the second test fails"
+                    { Fixture.stringifyNumbers = True
                     }
             },
           (Fixture.fixture $ Fixture.Backend Postgres.backendTypeMetadata)
@@ -240,3 +239,44 @@ tests = do
               |]
 
       shouldReturnYaml testEnvironment actual expected
+
+    it "Fetch __typename for an aggregate" \testEnvironment -> do
+      let schemaName :: Schema.SchemaName
+          schemaName = Schema.getSchemaName testEnvironment
+
+      -- SQL Server returns int type when the input is of int type, which is different than the rest.
+      -- https://learn.microsoft.com/en-us/sql/t-sql/functions/avg-transact-sql?view=sql-server-ver16#return-types
+      let avgResult :: String
+          avgResult
+            | fmap BackendType.backendType (getBackendTypeConfig testEnvironment) == Just Fixture.SQLServer = "3"
+            | otherwise = "3.25"
+
+      let expected :: Value
+          expected =
+            [interpolateYaml|
+              data:
+                #{schemaName}_article_aggregate:
+                  aggregate:
+                    avg:
+                      rating: #{avgResult}
+                      __typename: #{schemaName}_article_avg_fields
+            |]
+
+          actual :: IO Value
+          actual =
+            postGraphql
+              testEnvironment
+              [graphql|
+                query {
+                  #{schemaName}_article_aggregate {
+                    aggregate {
+                      avg {
+                        rating
+                        __typename
+                      }
+                    }
+                  }
+                }
+              |]
+
+      shouldReturnYaml testEnvironment actual expected
diff --git a/server/src-lib/Hasura/Backends/BigQuery/ToQuery.hs b/server/src-lib/Hasura/Backends/BigQuery/ToQuery.hs
@@ -469,6 +469,11 @@ fromNullAggregate = \case
 fromAggregate :: Aggregate -> Printer
 fromAggregate =
   \case
+    -- There's no reason why we'd be aggregating a ValueExpression /unless/
+    -- that ValueExpression is a reserved GraphQL name like __typename. In
+    -- which case, we don't want to run it through the aggregation function;
+    -- we just want to return the value.
+    OpAggregate _ (ValueExpression (TypedValue ty val)) -> fromValue ty val
     CountAggregate countable -> "COUNT(" <+> fromCountable countable <+> ")"
     OpAggregate text arg ->
       UnsafeTextPrinter text <+> "(" <+> fromExpression arg <+> ")"
@@ -480,10 +485,8 @@ fromAggregate =
               ", "
               ( map
                   ( \(alias, arg) ->
-                      UnsafeTextPrinter text
-                        <+> "("
-                        <+> fromExpression arg
-                        <+> ") AS "
+                      fromAggregate (OpAggregate text arg)
+                        <+> " AS "
                         <+> fromNameText alias
                   )
                   (toList args)