Concurrent Mutations Fail with Unique Index Constraint After v24.0.5 Upgrade

[escquery]

After upgrading Dgraph to v24.0.5 and adding a unique index to system_id, executing multiple Mutations concurrently results in an error.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/dgraph-io/dgo/v240"
	"github.com/dgraph-io/dgo/v240/protos/api"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
)

func mutation() {
	conn, err := grpc.NewClient("localhost:9080", grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil {
		log.Fatal(err)
	}
	defer conn.Close()
	dg := dgo.NewDgraphClient(api.NewDgraphClient(conn))
	mu1 := &api.Mutation{
		SetNquads: []byte(`_:system <system_id> "test1" .
_:system <system_name> "test1" .
_:system <create_time> "2023-04-01T06:34:52.643148+08:00" .
_:system <update_time> "2023-04-01T06:34:52.643148+08:00" .
_:system <dgraph.type> "System" .
`),
		CommitNow: true,
	}
	mu2 := &api.Mutation{
		DelNquads: []byte(`<0xef9093> * * .
<0x4fb5> <env_systems> <0xef9093> .
`),
		CommitNow: true,
	}
	req := &api.Request{
		Mutations: []*api.Mutation{mu1, mu2},
		CommitNow: true,
	}

	response, err := dg.NewTxn().Do(context.Background(), req)
	if err != nil {
		log.Fatal(err)
	}
	fmt.Printf("%v\n", response)
}

func main() {
	mutation()
}

The error details are as follows:

2024/12/04 14:10:44 rpc error: code = Unknown desc = while lexing {__dgraph_uniquecheck_0__ as var(func: eq(system_id,"test1"))__dgraph_uniquecheck_0__ as var(func: eq(system_id,"test1"))}} at line 1 column 122: Too many right curl
exit status 1

If I swap the order of m1 and m2, the issue does not occur. It appears that multiple set mutations cannot be performed simultaneously.

[shivaji-kharse]

This is not related to Dgo. It is a bug in Dgraph, and this PR will fix the issue.