Need help parsing cypher result

[Beetroot2314]

Hey, I have the following code on my golang project -

result, err := neo4j.ExecuteQuery(ctx, driver, query, nil, neo4j.EagerResultTransformer, neo4j.ExecuteQueryWithDatabase("neo4j"))
if err != nil {
	panic(err)
}
log.Printf("results: %v", result)
for _, record := range result.Records {
	log.Printf("Record: %v", record)
	if value, ok := record.Get("friend"); ok {
		log.Printf("Value: %v", value)
	}
}

I am unable to properly parse the result.
These are the following logs I am getting-

2024/05/28 23:32:30 results: &{[friend] [0xc000088240] 0xc000067c60}
2024/05/28 23:32:30 Record: &{[{0 4:a88a8293-4d0c-4906-9910-f5401dc8950d:0 [Student] map[class:5 id:1 name:John]}] [friend]}
2024/05/28 23:32:30 Value: {0 4:a88a8293-4d0c-4906-9910-f5401dc8950d:0 [Student] map[class:5 id:1 name:John]}

What I wish to pick from this is map[class:5 id:1 name:John]
Please tell me how that can be done?

[fbiville]

Hello @Beetroot2314, can you share what the query looks like as well, please?

[Beetroot2314]

Hey, sorry for the late reply. I appreciate your response.

I was using the following query in my code -

MATCH (start:Student {id: 2})-[:FRIEND* 3 .. 3]->(friend:Student)
WHERE NOT start = friend
RETURN DISTINCT friend

I figured that this would work on Neo4j Workspace but for my code I should've simply selected the fields that I wanted to retrieve, so I used the following -

MATCH (start:Student {id: 2})-[:FRIEND* 3 .. 3]->(friend:Student)
WHERE NOT start = friend
RETURN DISTINCT {
class: friend.class,
id: friend.id,
name: friend.name
}
AS friendMap

I had to end up parsing this as a json and converting it into a map and then finally I was able to pick values from this map (but do let me know if there's a better way to do that, I'm actually new to golang and neo4j altogether)

Thanks! :)

[fbiville]

There's no direct support for mapping from/to JSON but there a few generic helpers that can help you with what you're doing, see the calls to neo4j.GetRecordValue (to map a raw record to instance of type T) and neo4j.GetProperty (to extract properties of nodes and relationships and map them to a type T):

import (
	"context"
	"fmt"
	"github.com/neo4j/neo4j-go-driver/v5/neo4j"
)

func fetchFriendsOf(ctx context.Context, driver neo4j.DriverWithContext, id int) ([]Student, error) {
	query := `
		MATCH (start:Student {id: $id})-[:FRIEND*3..3]->(friend:Student)
		WHERE start <> friend
		RETURN DISTINCT friend
	`
	parameters := map[string]any{
		"id": id,
	}
	result, err := neo4j.ExecuteQuery(ctx, driver, query, parameters, neo4j.EagerResultTransformer, neo4j.ExecuteQueryWithDatabase("neo4j"))
	// handleError(err)
	var results []Student
	for _, record := range result.Records {
		friend, _, err := neo4j.GetRecordValue[neo4j.Node](record, "friend")
		// handleError(err)
		id, err := neo4j.GetProperty[int64](friend, "id")
		// handleError(err)
		class, err := neo4j.GetProperty[string](friend, "class")
		// handleError(err)
		name, err := neo4j.GetProperty[string](friend, "name")
		// handleError(err)
		results = append(results, Student{
			Id:    id,
			Class: class,
			Name:  name,
		})
	}
        return results, nil
}
	
type Student struct {
	Id    int64
	Class string
	Name  string
}

func (s Student) String() string {
	return fmt.Sprintf("Student {Id: %s, Class: %s, Name: %s}", s.Id, s.Class, s.Name)
}	

note: I haven't tested this code, so you may need to adjust it a little bit (and I omitted error handling for brevity)