Fix custom function calls on the HTTP interface (#4998)

The problem was that, if no global variables were passed,
we were passing in NULL for the global variable JSON object,
which causes strict functions to spuriously return NULL.

Fixes #4989

edb/server/protocol/edgeql_ext.pyx

@@ -125,7 +125,7 @@ async def handle_request(
             db,
             query,
             variables=variables or {},
-            globals_=globals_ or {},
+            globals_=globals_,
         )
     except Exception as ex:
         if debug.flags.server:

edb/server/protocol/execute.pyx

@@ -400,7 +400,7 @@ async def parse_execute_json(
     query: str,
     *,
     variables: Mapping[str, Any] = immutables.Map(),
-    globals_: Mapping[str, Any] = immutables.Map(),
+    globals_: Optional[Mapping[str, Any]] = None,
     output_format: compiler.OutputFormat = compiler.OutputFormat.JSON,
     query_cache_enabled: Optional[bool] = None,
 ) -> bytes:
@@ -443,20 +443,19 @@ async def execute_json(
     dbv: dbview.DatabaseConnectionView,
     compiled: dbview.CompiledQuery,
     variables: Mapping[str, Any] = immutables.Map(),
-    globals_: Mapping[str, Any] = immutables.Map(),
+    globals_: Optional[Mapping[str, Any]] = None,
     *,
     fe_conn: Optional[frontend.FrontendConnection] = None,
     use_prep_stmt: bint = False,
 ) -> bytes:
-    if globals_:
-        dbv.set_globals(immutables.Map({
-            "__::__edb_json_globals__": config.SettingValue(
-                name="__::__edb_json_globals__",
-                value=_encode_json_value(globals_),
-                source='global',
-                scope=qltypes.ConfigScope.GLOBAL,
-            )
-        }))
+    dbv.set_globals(immutables.Map({
+        "__::__edb_json_globals__": config.SettingValue(
+            name="__::__edb_json_globals__",
+            value=_encode_json_value(globals_),
+            source='global',
+            scope=qltypes.ConfigScope.GLOBAL,
+        )
+    }))
 
     qug = compiled.query_unit_group
 

tests/schemas/graphql.esdl

@@ -162,8 +162,14 @@ function get_glob() -> optional str using (global test_global_str);
 
 alias GlobalTest := {
     gstr := global test_global_str,
-	garray := global test_global_array,
-	gid := global test_global_id,
-	gdef := global test_global_def,
-	gdef2 := global test_global_def2,
+    garray := global test_global_array,
+    gid := global test_global_id,
+    gdef := global test_global_def,
+    gdef2 := global test_global_def2,
+};
+
+function id_func(s: str) -> str using (s);
+
+alias FuncTest := {
+    fstr := id_func('test'),
 };

tests/test_http_edgeql.py

@@ -326,3 +326,23 @@ def test_http_edgeql_query_globals_03(self):
                 globals={'default::test_global_str': 'foo'},
                 use_http_post=use_http_post,
             )
+
+    def test_http_edgeql_query_globals_04(self):
+        Q = r'''select get_glob()'''
+
+        for use_http_post in [True, False]:
+            self.assert_edgeql_query_result(
+                Q,
+                [],
+                use_http_post=use_http_post,
+            )
+
+    def test_http_edgeql_query_func_01(self):
+        Q = r'''select id_func('foo')'''
+
+        for use_http_post in [True, False]:
+            self.assert_edgeql_query_result(
+                Q,
+                ['foo'],
+                use_http_post=use_http_post,
+            )

tests/test_http_graphql_query.py

@@ -4136,6 +4136,20 @@ def test_graphql_globals_01(self):
                 use_http_post=use_http_post,
             )
 
+    def test_graphql_func_01(self):
+        Q = r'''query { FuncTest { fstr } }'''
+
+        for use_http_post in [True, False]:
+            self.assert_graphql_query_result(
+                Q,
+                {
+                    "FuncTest": [{
+                        'fstr': 'test',
+                    }]
+                },
+                use_http_post=use_http_post,
+            )
+
 
 class TestGraphQLInit(tb.GraphQLTestCase):
     """Test GraphQL initialization on an empty database."""