如何在golang中编写bson形式的mongo查询?
我可以使用命令行查询查询mongodb集合以基于nfType和最小距离获取ipv4Addresses
db.nfinstancesdb.aggregate([ {
"$match": {
"nfType": "AMF"
}
},
{
"$unwind": "$ipv4Addresses"
},
{
$group: {
"_id": "$distance",
"ipv4Addresses": {
"$addToSet": "$ipv4Addresses"
}
}
},
{
"$sort": {
"_id": 1
}
},
{
"$limit": 1
}
])
这使输出预期为
[{"_id": 10,"ipv4Addresses": ["172.16.0.11","172.16.0.10"]}]
如何在Go上编写上述查询的bson形式?
我在下面的函数中执行了操作,但是获取了所有ipv4Addresses而不是上面的结果。
func (m *NfInstanceDataAccess) FindIp(nfType string) ([]NfInstance, error) { var ip []NfInstance
collection := db.C(COLLECTION)
pipeline := mongo.Pipeline{
{{"$match", bson.D{
{"nfType", "AMF"},
}}},
{{"$unwind", "$ipv4Addresses"}},
{{"$group", bson.D{
{"_id", "$distance"},
{"ipv4Addresses", bson.D{
{"$addToSet", "$ipv4Addresses"},
}},
}}},
{{"$sort", bson.D{
{"_id", 1},
}}},
{{"$limit", 1}},
}
cursor, err := collection.Aggregate(context.Background(), pipeline)
defer cursor.Close(context.Background())
for cursor.Next(context.Background()) {
var ip []NfInstance
err := cursor.Decode(&ip)
if err != nil {
log.Fatal(err)
}
//fmt.Println(doc)
}
return ip, nil
}
我的有以下物品
{ "nfInstanceID": "1",
"nfType": [
"AMF"
],
"nfStatus": [
"REGISTERED"
],
"ipv4Addresses": [
"172.16.0.10"
],
"distance": 10
},
{
"nfInstanceID": "2",
"nfType": [
"UPF"
],
"nfStatus": [
"REGISTERED"
],
"ipv4Addresses": [
"172.16.0.20"
],
"distance": 20
},
{
"nfInstanceID": "3",
"nfType": [
"AMF"
],
"nfStatus": [
"REGISTERED"
],
"ipv4Addresses": [
"172.16.0.30"
],
"distance": 30
},
{
"nfInstanceID": "4",
"nfType": [
"AMF"
],
"nfStatus": [
"REGISTERED"
],
"ipv4Addresses": [
"172.16.0.11"
],
"distance": 10
}
我期望输出相同或相似。
回答:
您的golang代码存在的问题是您没有分组。
您可以利用Pipe
它来准备管道以进行聚合:
pipe := db.C(COLLECTION).Pipe([]bson.M{ {"$match": bson.M{"nfType": "AMF"}},
{"$unwind": "$ipv4Addresses"},
{"$group": bson.M{
"_id": "$distance",
"ipv4Addresses": bson.M{"$addToSet": "$ipv4Addresses"},
}},
{"$sort": bson.M{"_id": 1}},
{"$limit": 1},
})
err := pipe.All(&ip)
以上是 如何在golang中编写bson形式的mongo查询? 的全部内容, 来源链接: utcz.com/qa/428157.html