test: added e2e test

Signed-off-by: Harshit Gangal <harshit@planetscale.com>

go/test/endtoend/vtgate/foreignkey/fk_test.go

@@ -53,3 +53,32 @@ func TestInsertions(t *testing.T) {
 	_, err = utils.ExecAllowError(t, conn, `insert into multicol_tbl2(cola, colb, colc, msg) values (103, 'c', 'd', 'msg2')`)
 	require.ErrorContains(t, err, "Cannot add or update a child row: a foreign key constraint fails")
 }
+
+// TestDeletions tests that deletions work as expected when foreign key management is enabled in Vitess.
+func TestDeletions(t *testing.T) {
+	conn, closer := start(t)
+	defer closer()
+
+	// insert some data.
+	utils.Exec(t, conn, `insert into t1(id, col) values (100, 123),(10, 12),(1, 13),(1000, 1234)`)
+	utils.Exec(t, conn, `insert into t2(id, col) values (100, 125), (1, 132)`)
+	utils.Exec(t, conn, `insert into t4(id, col) values (1, 321)`)
+	utils.Exec(t, conn, `insert into multicol_tbl1(cola, colb, colc, msg) values (100, 'a', 'b', 'msg'), (101, 'c', 'd', 'msg2')`)
+	utils.Exec(t, conn, `insert into multicol_tbl2(cola, colb, colc, msg) values (100, 'a', 'b', 'msg3')`)
+
+	// child foreign key is shard scoped. Query will fail at mysql due to On Delete Restrict.
+	_, err := utils.ExecAllowError(t, conn, `delete from t2 where col = 132`)
+	require.ErrorContains(t, err, "Cannot delete or update a parent row: a foreign key constraint fails")
+
+	// child row does not exist so query will succeed.
+	qr := utils.Exec(t, conn, `delete from t2 where col = 125`)
+	require.EqualValues(t, 1, qr.RowsAffected)
+
+	// table's child foreign key has cross shard fk, so query will fail at vtgate.
+	_, err = utils.ExecAllowError(t, conn, `delete from t1 where id = 42`)
+	require.ErrorContains(t, err, "VT12002: unsupported: foreign keys management at vitess (errno 1235) (sqlstate 42000)")
+
+	// child foreign key is cascade, so query will fail at vtgate.
+	_, err = utils.ExecAllowError(t, conn, `delete from multicol_tbl1 where cola = 100`)
+	require.ErrorContains(t, err, "VT12002: unsupported: foreign keys management at vitess (errno 1235) (sqlstate 42000)")
+}

go/test/endtoend/vtgate/foreignkey/main_test.go

@@ -91,7 +91,7 @@ func start(t *testing.T) (*mysql.Conn, func()) {
 
 	deleteAll := func() {
 		_ = utils.Exec(t, conn, "use `ks/-80`")
-		tables := []string{"t3", "t2", "t1", "multicol_tbl2", "multicol_tbl1"}
+		tables := []string{"t4", "t3", "t2", "t1", "multicol_tbl2", "multicol_tbl1"}
 		for _, table := range tables {
 			_ = utils.Exec(t, conn, "delete from "+table)
 		}

go/test/endtoend/vtgate/foreignkey/sharded_schema.sql

@@ -10,15 +10,15 @@ create table t2
     id    bigint,
     col   bigint,
     primary key (id),
-    foreign key (id) references t1 (id)
+    foreign key (id) references t1 (id) on delete restrict
 ) Engine = InnoDB;
 
 create table t3
 (
     id    bigint,
     col   bigint,
     primary key (id),
-    foreign key (col) references t1 (id)
+    foreign key (col) references t1 (id) on delete restrict
 ) Engine = InnoDB;
 
 create table multicol_tbl1
@@ -37,5 +37,13 @@ create table multicol_tbl2
     colc varchar(50),
     msg  varchar(50),
     primary key (cola, colb, colc),
-    foreign key (cola, colb, colc) references multicol_tbl1 (cola, colb, colc)
+    foreign key (cola, colb, colc) references multicol_tbl1 (cola, colb, colc) on delete cascade
+) Engine = InnoDB;
+
+create table t4
+(
+    id    bigint,
+    col   bigint,
+    primary key (id),
+    foreign key (id) references t2 (id) on delete restrict
 ) Engine = InnoDB;

go/test/endtoend/vtgate/foreignkey/sharded_vschema.json

@@ -39,6 +39,14 @@
         }
       ]
     },
+    "t4": {
+      "column_vindexes": [
+        {
+          "column": "id",
+          "name": "xxhash"
+        }
+      ]
+    },
     "multicol_tbl1": {
       "column_vindexes": [
         {