go版本：1.20
nebula-graph版本：3.4.0
NebulaGraph Go客户端版本：V3，3.4.0
----a.go文件—
package my_nebula_graph
import (
"fmt"
nebula "github.com/vesoft-inc/nebula-go/v3"
)
type NebulaGraphConfig struct {
Address string
Port int
Username string
Password string
}
var NebulaGraphSession *nebula.Session
func Init(c *NebulaGraphConfig) {
hostAddress := nebula.HostAddress{Host: c.Address, Port: c.Port}
hostList := []nebula.HostAddress{hostAddress}
testPoolConfig := nebula.GetDefaultConf()
var logInfo = nebula.DefaultLogger{}
pool, err := nebula.NewConnectionPool(hostList, testPoolConfig, logInfo)
if err != nil {
fmt.Println("----123----", err)
}
defer pool.Close()
session, err := pool.GetSession(c.Username, c.Password)
if err != nil {
fmt.Println("----456----", err)
}
defer session.Release()
NebulaGraphSession = session
}
----b.go文件—
package test
import (
"fmt"
"testing"
"demo/common/my_nebula_graph"
)
func TestGolang(t *testing.T) {
my_nebula_graph.Init(&my_nebula_graph.NebulaGraphConfig{
Address: "192.168.1.201",
Port: 9669,
Username: "root",
Password: "test",
})
sql := "USE test;"
res, err := my_nebula_graph.NebulaGraphSession.Execute(sql)
if err != nil {
fmt.Print("报错00：", err.Error())
}
if !res.IsSucceed() {
fmt.Sprintf("45600, %s, ErrorCode: %v, ErrorMsg: %s", sql, res.GetErrorCode(), res.GetErrorMsg())
}
}
报错如下
=== RUN TestGolang
报错00：failed to execute: Session has been released
--- FAIL: TestGolang (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x0 pc=0xcae4c4]
重新编辑了，报错已贴上，
我就想在一个地方初始化，然后多个地方使用，不能这样使用吗？
1 个赞
Aiee
6
你 init 里 release 掉了后面自然用不了
init 里 不要 defer session.Release() 这句吗，，去掉这句就会报下面的错误
=== RUN TestGolang
报错00：Connection not open
--- FAIL: TestGolang (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x0 pc=0x108d8c4]
因为我要在接口中操作 NebulaGraph
改成下面这样也不行
-----a.go------
package my_nebula_graph
import (
nebula "github.com/vesoft-inc/nebula-go/v3"
)
type NebulaGraphConfig struct {
Address string
Port int
Username string
Password string
}
func Init(c *NebulaGraphConfig) (*nebula.Session, error) {
hostAddress := nebula.HostAddress{Host: c.Address, Port: c.Port}
hostList := []nebula.HostAddress{hostAddress}
testPoolConfig := nebula.GetDefaultConf()
var logInfo = nebula.DefaultLogger{}
pool, err := nebula.NewConnectionPool(hostList, testPoolConfig, logInfo)
if err != nil {
return nil, err
}
defer pool.Close()
session, err := pool.GetSession(c.Username, c.Password)
if err != nil {
return nil, err
}
defer session.Release()
return session, nil
}
------b.go-------
package test
import (
"fmt"
"demo/common/my_nebula_graph"
nebula "github.com/vesoft-inc/nebula-go/v3"
)
type TestInterface interface {
RunQuery(query string)
}
type TestStruct struct {
client *nebula.Session
}
func NewTest() *TestStruct {
c, err := my_nebula_graph.Init(&my_nebula_graph.NebulaGraphConfig{
Address: "192.168.1.201",
Port: 9669,
Username: "root",
Password: "nebula123",
})
if err != nil {
fmt.Println(err)
}
return &TestStruct{
client: c,
}
}
func (s *TestStruct) RunQuery(query string) {
res, err := s.client.Execute(query)
if err != nil {
fmt.Println(err)
}
if !res.IsSucceed() {
fmt.Sprintf("%s, ErrorCode: %v, ErrorMsg: %s", query, res.GetErrorCode(), res.GetErrorMsg())
}
}
------c.go------
package test
import (
"testing"
)
func TestGolang(t *testing.T) {
l := NewTest()
l.RunQuery("USE test;")
}
c.go运行报下面的错
=== RUN TestGolang
failed to execute: Session has been released
--- FAIL: TestGolang (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x0 pc=0x116e28f]
我在处理redis或者其他数据库（包括dgraph），都是这样来操作的，，都没问题，就是nebula-graph老报错，指点一下，不会每次运行nebula-graph命令，都要重新初始化，
nebula.NewConnectionPool(）
pool.GetSession(）
生成session吧，如果这样，是不是太鸡肋了
你的函数在 Init 方法结束后就执行了 defer session.Release() 此时，session 已经关闭。而且在日志中也说明了 failed to execute: Session has been released
哪要怎么改，init中把 defer session.Release() 干掉，会报下面的错
=== RUN TestGolang
Connection not open
--- FAIL: TestGolang (0.00s)
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x0 pc=0xbcd66f]
不会每次运行nebula-graph命令，都要重新初始化
nebula.NewConnectionPool(）
pool.GetSession(）
生成session吧，如果这样，是不是太鸡肋了