Question

我在访问aws-sdk-go时遇到问题，我正在尝试使用aws-sdk-go连接到dynamo DB。我能够建立与数据库的连接并且插入操作工作正常，但是当我尝试从表中检索数据时，我得到了＃34;恐慌运行时错误无效的内存地址或者nil指针取消引用golang＆＃34;错误。请查找我使用的代码。我是这两种技术的新手。

package main 
import (
  "github.com/aws/aws-sdk-go/aws"
  "github.com/aws/aws-sdk-go/aws/session"
  "github.com/aws/aws-sdk-go/aws/credentials"
  "github.com/aws/aws-sdk-go/service/dynamodb"
  "github.com/user/dynamo_connect/data"
  "github.com/user/insert_api/read"
)
import (
  "fmt"
  "log"
  "net/http"
  "crypto/md5"
  "encoding/hex"
  "io"
  "time"
  "github.com/gorilla/mux"
)

func main() {
  router := mux.NewRouter().StrictSlash(true)
  router.HandleFunc("/get", GetCampaignRecord)
  log.Fatal(http.ListenAndServe(":8080", router))
}

func GetCampaignRecord(w http.ResponseWriter, r *http.Request) {
  var testCredentials = credentials.NewStaticCredentials("AKIxxxxxxxxxxxxxxxxx", "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", "")
  sess, err := session.NewSession()
  svc := dynamodb.New(sess, &aws.Config{
    Region: aws.String("ap-south-1"),
    Credentials: testCredentials,
  })

  resp, err := read.GetCampaignData(svc)
  if err != nil {
    fmt.Println("An error occurred while writing to the Employee table")
    fmt.Println(err.Error())
  }

  if resp != nil {
    fmt.Println("An error occurred while writing to the Employee table")
    fmt.Println(err.Error())
  }
}

包阅读

    package read
    import "github.com/aws/aws-sdk-go/service/dynamodb"
    import "github.com/aws/aws-sdk-go/aws"

    func GetCampaignData(svc *dynamodb.DynamoDB) (*dynamodb.BatchGetItemOutput, error) {
      params := &dynamodb.BatchGetItemInput{
        RequestItems: map[string]*dynamodb.KeysAndAttributes{
            "employee": {
                Keys: []map[string]*dynamodb.AttributeValue{
                    {
                        "employee_id": {
                            S:    aws.String("1"),
                        },
                    },
                },
                ProjectionExpression: aws.String("employee_id, employee_name"),
            },
        },
        ReturnConsumedCapacity: aws.String("TOTAL"),
    }

    return svc.BatchGetItem(params)
    }

完全错误我正在

http：panic serving 127.0.0.1:36034：运行时错误：无效的内存地址或无指针取消引用 goroutine 18 [跑步]：净/ HTTP（*康恩）.serve.func1（0xc820102000） /usr/local/go/src/net/http/server.go:1389 + 0xc1 恐慌（0x8919a0,0xc82000a110） /usr/local/go/src/runtime/panic.go:443 + 0x4e9 github.com/aws/aws-sdk-go/aws/session.(*Session).Copy(0x0,0xc82012a020,0x1,0x1,0x0） /home/MyUser/work/src/github.com/aws/aws-sdk-go/aws/session/session.go:365 + 0x2a github.com/aws/aws-sdk-go/aws/session.(*Session).ClientConfig(0x0,0x935410,0x8,0xc82012a020,0x1,0x1,0x0,0x0,0x0,0x0, ......） /home/MyUser/work/src/github.com/aws/aws-sdk-go/aws/session/session.go:378 + 0x72 github.com/aws/aws-sdk-go/service/dynamodb.New(0x7f20477cd248,0x0,0xc82012a020,0x1,0x1,0xc820112260） /home/MyUser/work/src/github.com/aws/aws-sdk-go/service/dynamodb/service.go:153 + 0x78 main.GetCampaignRecord（0x7f20477cd058,0xc820122000,0xc82010e000） /home/MyUser/work/src/github.com/user/insert_api/insert_api.go:80 + 0x329 net / http.HandlerFunc.ServeHTTP（0xa07d38,0x7f20477cd058,0xc820122000,0xc82010e000） /usr/local/go/src/net/http/server.go:1618 + 0x3a github.com/gorilla/mux.(*Router).ServeHTTP(0xc8200125a0,0x7f20477cd058,0xc820122000,0xc82010e000） /home/MyUser/work/src/github.com/gorilla/mux/mux.go:114 + 0x2a8 net / http.serverHandler.ServeHTTP（0xc82006e180,0x7f20477cd058,0xc820122000,0xc82010e000） /usr/local/go/src/net/http/server.go:2081 + 0x19e 净/ HTTP（*康恩）.serve（0xc820102000） /usr/local/go/src/net/http/server.go:1472 + 0xf2e 由net / http。（* Server）.Serve创建 /usr/local/go/src/net/http/server.go:2137 + 0x44e 2016/11/19 13:31:34 http：panic serving 127.0.0.1:36035：运行时错误：无效的内存地址或nil指针取消引用 goroutine 5 [正在运行]：净/ HTTP（*康恩）.serve.func1（0xc82006e200） /usr/local/go/src/net/http/server.go:1389 + 0xc1 恐慌（0x8919a0,0xc82000a110） /usr/local/go/src/runtime/panic.go:443 + 0x4e9 github.com/aws/aws-sdk-go/aws/session.(*Session).Copy(0x0,0xc82012a038,0x1,0x1,0x0） /home/MyUser/work/src/github.com/aws/aws-sdk-go/aws/session/session.go:365 + 0x2a github.com/aws/aws-sdk-go/aws/session.(*Session).ClientConfig(0x0,0x935410,0x8,0xc82012a038,0x1,0x1,0x0,0x0,0x0,0x0, ......） /home/MyUser/work/src/github.com/aws/aws-sdk-go/aws/session/session.go:378 + 0x72 github.com/aws/aws-sdk-go/service/dynamodb.New(0x7f20477cd248,0x0,0xc82012a038,0x1,0x1,0xc820112540） /home/MyUser/work/src/github.com/aws/aws-sdk-go/service/dynamodb/service.go:153 + 0x78 main.GetCampaignRecord（0x7f20477cd058,0xc8201224e0,0xc8200d20e0） /home/MyUser/work/src/github.com/user/insert_api/insert_api.go:80 + 0x329 net / http.HandlerFunc.ServeHTTP（0xa07d38,0x7f20477cd058,0xc8201224e0,0xc8200d20e0） /usr/local/go/src/net/http/server.go:1618 + 0x3a github.com/gorilla/mux.(*Router).ServeHTTP(0xc8200125a0,0x7f20477cd058,0xc8201224e0,0xc8200d20e0） /home/MyUser/work/src/github.com/gorilla/mux/mux.go:114 + 0x2a8 net / http.serverHandler.ServeHTTP（0xc82006e180,0x7f20477cd058,0xc8201224e0,0xc8200d20e0） /usr/local/go/src/net/http/server.go:2081 + 0x19e 净/ HTTP（*康恩）.serve（0xc82006e200） /usr/local/go/src/net/http/server.go:1472 + 0xf2e 由net / http。（* Server）.Serve创建 /usr/local/go/src/net/http/server.go:2137 + 0x44e 2016/11/19 13:31:34 http：panic serving 127.0.0.1:36036：运行时错误：无效的内存地址或nil指针取消引用 goroutine 34 [跑步]：净/ HTTP（*康恩）.serve.func1（0xc820114280） /usr/local/go/src/net/http/server.go:1389 + 0xc1 恐慌（0x8919a0,0xc82000a110） /usr/local/go/src/runtime/panic.go:443 + 0x4e9 github.com/aws/aws-sdk-go/aws/session.(*Session).Copy(0x0,0xc82012a058,0x1,0x1,0x0） /home/MyUser/work/src/github.com/aws/aws-sdk-go/aws/session/session.go:365 + 0x2a github.com/aws/aws-sdk-go/aws/session.(*Session).ClientConfig(0x0,0x935410,0x8,0xc82012a058,0x1,0x1,0x0,0x0,0x0,0x0, ......） /home/MyUser/work/src/github.com/aws/aws-sdk-go/aws/session/session.go:378 + 0x72 github.com/aws/aws-sdk-go/service/dynamodb.New(0x7f20477cd248,0x0,0xc82012a058,0x1,0x1,0xc820112840） /home/MyUser/work/src/github.com/aws/aws-sdk-go/service/dynamodb/service.go:153 + 0x78 main.GetCampaignRecord（0x7f20477cd058,0xc820122820,0xc82016c000） /home/MyUser/work/src/github.com/user/insert_api/insert_api.go:80 + 0x329 net / http.HandlerFunc.ServeHTTP（0xa07d38,0x7f20477cd058,0xc820122820,0xc82016c000） /usr/local/go/src/net/http/server.go:1618 + 0x3a github.com/gorilla/mux.(*Router).ServeHTTP(0xc8200125a0,0x7f20477cd058,0xc820122820,0xc82016c000） /home/MyUser/work/src/github.com/gorilla/mux/mux.go:114 + 0x2a8 net / http.serverHandler.ServeHTTP（0xc82006e180,0x7f20477cd058,0xc820122820,0xc82016c000） /usr/local/go/src/net/http/server.go:2081 + 0x19e 净/ HTTP（*康恩）.serve（0xc820114280） /usr/local/go/src/net/http/server.go:1472 + 0xf2e 由net / http。（* Server）.Serve创建 /usr/local/go/src/net/http/server.go:2137 + 0x44e

Answer 1

我已经完成了您的代码，在我看来，您的数据库连接存在问题。您正在尝试连接到某个不同的区域。所以，请先重新检查你所在的地区。它存在于您的dynamodb的AWS账户的URL中（例如us-east-2）。您还可以通过在终端中键入以下命令来检查或配置您的区域：aws configure。然后它会要求您输入您的访问密钥，密钥，区域名称等。在此处输入所有详细信息。而已。干杯。

使用golang

1 个答案: