feat:#10 added new minimal backend

datamanager/backend/dbx/db.go

@@ -0,0 +1,90 @@
+package dbx
+
+import (
+	"context"
+	"database/sql"
+	"github.com/neo4j/neo4j-go-driver/v5/neo4j"
+	"log/slog"
+)
+
+type (
+	DB struct {
+		driver neo4j.DriverWithContext
+		ctx    context.Context
+	}
+
+	// Errors represents a list of errors.
+	Errors []error
+)
+
+func NewDB(username string, password string) *DB {
+	driver, err := neo4j.NewDriverWithContext("bolt://localhost:7687", neo4j.BasicAuth(username, password, ""))
+	if err != nil {
+		slog.Error("Failed to create a new driver: %v", err)
+		return nil
+	}
+
+	return &DB{
+		driver: driver,
+		ctx:    context.Background(),
+	}
+}
+
+// Context returns the context associated with the DB instance.
+// It returns nil if no context is associated.
+func (db *DB) Context() context.Context {
+	return db.ctx
+}
+
+// Close closes the database, releasing any open resources.
+func (db *DB) Close() error {
+	if db.driver != nil {
+		return db.driver.Close(db.ctx)
+	}
+	return nil
+
+}
+
+// Executor prepares, executes, or queries a SQL statement.
+type Executor interface {
+	Query(query string, args ...interface{}) (*neo4j.ResultWithContext, error)
+	// QueryContext queries a SQL statement with the given context
+	QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)
+	// Prepare creates a prepared statement
+	Prepare(query string) (*sql.Stmt, error)
+}
+
+// Query represents a neo4j query that can be executed.
+type Query struct {
+	Executor          Executor
+	cypher, rawCypher string
+}
+
+func helloWorld(ctx context.Context, uri, username, password string) (string, error) {
+	driver, err := neo4j.NewDriverWithContext(uri, neo4j.BasicAuth(username, password, ""))
+	if err != nil {
+		return "", err
+	}
+
+	session := driver.NewSession(ctx, neo4j.SessionConfig{AccessMode: neo4j.AccessModeWrite})
+
+	greeting, err := session.ExecuteWrite(ctx, func(transaction neo4j.ManagedTransaction) (any, error) {
+		result, err := transaction.Run(ctx,
+			"CREATE (a:Greeting) SET a.message = $message RETURN a.message + ', from node ' + id(a)",
+			map[string]any{"message": "hello, world"})
+		if err != nil {
+			return nil, err
+		}
+
+		if result.Next(ctx) {
+			return result.Record().Values[0], nil
+		}
+
+		return nil, result.Err()
+	})
+	if err != nil {
+		return "", err
+	}
+
+	return greeting.(string), nil
+}