gorm中的外键

Question

here is my code :

package main

import (
    "fmt"
    "github.com/jinzhu/gorm"
    _ "github.com/jinzhu/gorm/dialects/sqlite"
)

type Mongo struct {
    gorm.Model
    Url      string
    Login    string
    Password string
    Env     string
    Base string
    Port string
}



type MicroService struct {
    gorm.Model
    Url        string
    Port       string
    Version    string
    Name       string
    Etat       string
    MongoDb    Mongo `gorm:"foreignkey:MongoId"`
    MongoId int
    Env     string
}



func initDb() {

    var mongoDb Mongo
    result := db.Find(&mongoDb, "env = ?", "Prod").RecordNotFound()
    fmt.Println("not found create mongodb")
    fmt.Println(result)
    if result == true {
        mongoDb = Mongo{}
        // "mongodb://heroku_4n1snp42:f42hkq6n3qfv48uelms7vrclta@:23930/heroku_4n1snp42"
        mongoDb.Url = "mlab.com"
        mongoDb.Login = "toto"
        mongoDb.Password = "titi"
        mongoDb.Base = "tata"
        mongoDb.Port = "23930"
        mongoDb.Env = "Prod"
        db.Create(&mongoDb)

    }
    var microService MicroService
    result = db.Find(&microService, "name = ? and env = ?", "constructProduct","Prod").RecordNotFound()
    fmt.Println("not found create construct Product Micro")
    fmt.Println(result)
    if result == true {
        microService = MicroService{}
        microService.Name  = "totobis"
        microService.Port = "8307"
        microService.Env = "Prod"
        var mongoDbConstructProduct Mongo
        result = db.Find(&mongoDbConstructProduct , "env = ?", "Prod").RecordNotFound()
        fmt.Println(mongoDbConstructProduct)
        microService.MongoDb = mongoDbConstructProduct
        db.Create(&microService)
        fmt.Println("constructProduct microservice created")
    }

}

var db *gorm.DB
var loggued bool





func main() {
    var err error
    loggued = false
    db, err = gorm.Open("sqlite3", "configuration.sqlite3?cache=shared&mode=rwc")
    db.AutoMigrate(&MicroService{})
    db.AutoMigrate(&Mongo{})

    initDb()
    var microService MicroService
    db.Find(&microService, "name = ?", "totobis").RecordNotFound()
    if err != nil {
        panic("failed to connect database")
    }
    defer db.Close()
    fmt.Println(microService)

}

But i don't understand why when i print the object after query it , the mongodb of MicroService is empty.

When i print the field mongodb in the creation it's ok :

{{1 2018-11-26 22:08:16.436503737 +0100 +0100 2018-11-26 22:08:16.504275897 +0100 +0100 } mlab.com toto titi Prod tata 23930}

But when i try to recreate a microservice object the mongo field is empty :

{{2 2018-11-26 22:09:15.73203579 +0100 +0100 2018-11-26 22:09:15.73203579 +0100 +0100 } 8307 totobis {{0 0001-01-01 00:00:00 +0000 UTC 0001-01-01 00:00:00 +0000 UTC } } 1 Prod}

How can I do to get the good microservice struct with the mongo struct I've associated?

Answer 1

MongoId is a uint data type, not int.

in another way you can use an int field in Mongo model as :

type Mongo struct {
gorm.Model
Ms int // for example
....
}

and then in MicroService model :

type MicroService struct {
gorm.Model
Url        string
Port       string
Version    string
Name       string
Etat       string
MongoDb    Mongo `gorm:"foreignkey:MongoId;association_foreignkey:Ms"`
MongoId int
Env     string
}