如何在v2 Go SDK中使用KeyConditionExpression查询AWS DynamoDb

我用以下命令在dynamodb中创建了一个现有表

aws dynamodb create-table \
  --region us-east-1 \
  --table-name notifications \
  --attribute-definitions AttributeName=CustomerId,AttributeType=S AttributeName=Timestamp,AttributeType=N AttributeName=MessageId,AttributeType=S \
  --key-schema AttributeName=CustomerId,KeyType=HASH AttributeName=Timestamp,KeyType=RANGE \
  --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5 \
  --global-secondary-indexes '[
      {
          "IndexName": "MessageId",
          "KeySchema": [
              {
                  "AttributeName": "MessageId",
                  "KeyType": "HASH"
              }
          ],
          "Projection": {
              "ProjectionType": "ALL"
          },
          "ProvisionedThroughput": {
              "ReadCapacityUnits": 5,
              "WriteCapacityUnits": 5
          }
      }
  ]'
}

我想在前面放一个API包装器，它允许我从CustomerId的表中获取所有记录，所以我try 使用v2 Go SDK中的查询

// GET /notifications/
func (api NotificationsApi) getNotifications(w http.ResponseWriter, r *http.Request) {
    var err error

    customerId := r.URL.Query().Get("customerId")
    if customerId == "" {
        api.errorResponse(w, "customerId query parameter required", http.StatusBadRequest)
        return
    }
    span, ctx := tracer.StartSpanFromContext(r.Context(), "notification.get")
    defer span.Finish(tracer.WithError(err))

    keyCond := expression.Key("CustomerId").Equal(expression.Value(":val"))
    expr, err := expression.NewBuilder().WithKeyCondition(keyCond).Build()

    input := &dynamodb.QueryInput{
        TableName:              aws.String("notifications"),
        KeyConditionExpression: expr.KeyCondition(),
        ExpressionAttributeValues: map[string]dynamodbTypes.AttributeValue{
            ":val": &dynamodbTypes.AttributeValueMemberS{Value: customerId},
        },
    }

    fmt.Println(*expr.KeyCondition())
    output, err := api.dynamoClient.Query(ctx, input)

    fmt.Println(output)
    fmt.Println(err)
}

但是，我从dynamodb得到了400分.

operation error DynamoDB: Query, https response error StatusCode: 400, RequestID: *****, api error ValidationException: Invalid KeyConditionExpression: An expression attribute name used in the document path is not defined; attribute name: #0

fmt.PrintLn(*expr.KeyCondition())的输出是#0 = :0

在本地运行此查询将返回预期结果

awslocal dynamodb query \
    --table-name notifications \
    --key-condition-expression "CustomerId = :val" \
    --expression-attribute-values '{":val":{"S":"localTesting"}}'

我也try 过包括时间戳，但我不认为这是必需的，因为我的终端命令没有它的工作.我不认为我取消引用是不恰当的.我知道我的发电机会话是有效的，因为我可以发布到我的包装器，并通过终端命令查看更新.