From e24fe507a0ca2c852a3c6ac0f63d532cc20fbf19 Mon Sep 17 00:00:00 2001
From: Jai Radhakrishnan <55522316+jairad26@users.noreply.github.com>
Date: Fri, 20 Dec 2024 00:04:25 -0800
Subject: [PATCH] fix query after delete

---
 api_helper.go  |  9 +++++++--
 api_reflect.go | 14 ++++++++++++--
 api_test.go    |  9 ++++++---
 api_types.go   |  6 ++++++
 4 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/api_helper.go b/api_helper.go
index bcd4928..0cda75b 100644
--- a/api_helper.go
+++ b/api_helper.go
@@ -187,6 +187,7 @@ func getByGid[T any](ctx context.Context, n *Namespace, gid uint64) (uint64, *T,
 	  obj(func: uid(%d)) {
 		uid
 		expand(_all_)
+		dgraph.type
 	  }
 	}
 	  `, gid)
@@ -203,6 +204,7 @@ func getByConstrainedField[T any](ctx context.Context, n *Namespace, cf Constrai
 	  obj(func: eq(%s, %s)) {
 		uid
 		expand(_all_)
+		dgraph.type
 	  }
 	}
 	  `, getPredicateName(t.Name(), cf.Key), cf.Value)
@@ -246,12 +248,15 @@ func executeGet[T any](ctx context.Context, n *Namespace, query string, cf *Cons
 
 	// Check if we have at least one object in the response
 	if len(result.Obj) == 0 {
-		return 0, nil, fmt.Errorf("no object found")
+		return 0, nil, ErrNoObjFound
 	}
 
 	// Map the dynamic struct to the final type T
 	finalObject := reflect.New(t).Interface()
-	gid := mapDynamicToFinal(result.Obj[0], finalObject)
+	gid, err := mapDynamicToFinal(result.Obj[0], finalObject)
+	if err != nil {
+		return 0, nil, err
+	}
 
 	return gid, finalObject.(*T), nil
 }
diff --git a/api_reflect.go b/api_reflect.go
index 817736e..be32e69 100644
--- a/api_reflect.go
+++ b/api_reflect.go
@@ -80,11 +80,15 @@ func createDynamicStruct(t reflect.Type, jsonFields map[string]string) reflect.T
 		Name: "Uid",
 		Type: reflect.TypeOf(""),
 		Tag:  reflect.StructTag(`json:"uid"`),
+	}, reflect.StructField{
+		Name: "DgraphType",
+		Type: reflect.TypeOf([]string{}),
+		Tag:  reflect.StructTag(`json:"dgraph.type"`),
 	})
 	return reflect.StructOf(fields)
 }
 
-func mapDynamicToFinal(dynamic any, final any) uint64 {
+func mapDynamicToFinal(dynamic any, final any) (uint64, error) {
 	vFinal := reflect.ValueOf(final).Elem()
 	vDynamic := reflect.ValueOf(dynamic).Elem()
 
@@ -99,6 +103,12 @@ func mapDynamicToFinal(dynamic any, final any) uint64 {
 			finalField = vFinal.FieldByName("Gid")
 			gidStr := value.String()
 			gid, _ = strconv.ParseUint(gidStr, 0, 64)
+		} else if field.Name == "DgraphType" {
+			fieldArr := value.Interface().([]string)
+			if len(fieldArr) == 0 {
+				final = nil
+				return 0, ErrNoObjFound
+			}
 		} else {
 			finalField = vFinal.FieldByName(field.Name)
 		}
@@ -111,5 +121,5 @@ func mapDynamicToFinal(dynamic any, final any) uint64 {
 			}
 		}
 	}
-	return gid
+	return gid, nil
 }
diff --git a/api_test.go b/api_test.go
index 4d2c7aa..5b1c6bc 100644
--- a/api_test.go
+++ b/api_test.go
@@ -181,9 +181,12 @@ func TestDeleteApi(t *testing.T) {
 	_, _, err = modusdb.Delete[User](db, gid, db1.ID())
 	require.NoError(t, err)
 
-	// TODO: when getting with uid, it returns an object with values set to 0 instead of an error
-	// _, queriedUser, err := modusdb.Get[User](db, gid, db1.ID())
-	_, queriedUser, err := modusdb.Get[User](db, modusdb.ConstrainedField{
+	_, queriedUser, err := modusdb.Get[User](db, gid, db1.ID())
+	require.Error(t, err)
+	require.Equal(t, "no object found", err.Error())
+	require.Nil(t, queriedUser)
+
+	_, queriedUser, err = modusdb.Get[User](db, modusdb.ConstrainedField{
 		Key:   "clerk_id",
 		Value: "123",
 	}, db1.ID())
diff --git a/api_types.go b/api_types.go
index 5d2f90d..9cea571 100644
--- a/api_types.go
+++ b/api_types.go
@@ -1,5 +1,11 @@
 package modusdb
 
+import "fmt"
+
+var (
+	ErrNoObjFound = fmt.Errorf("no object found")
+)
+
 type UniqueField interface {
 	uint64 | ConstrainedField
 }