Unable to run Go server due to "panic: reflect.StructOf: duplicate field"-CodePudding

I'm trying to create a backend API that contains 3 main models and 3 controllers but I'm running into trouble whenever I run go run main.go because it gives me this error message stating that I have a duplicate DeveloperID field:

[GIN-debug] [WARNING] Creating an Engine instance with the Logger and Recovery middleware already attached.

[GIN-debug] [WARNING] Running in "debug" mode. Switch to "release" mode in production.
 - using env:   export GIN_MODE=release
 - using code:  gin.SetMode(gin.ReleaseMode)

panic: reflect.StructOf: duplicate field DeveloperID

goroutine 1 [running]:
reflect.StructOf({0xc0003ee000, 0x3, 0xc00039e980})
        /snap/go/8627/src/reflect/type.go:2597  0x1d45
gorm.io/gorm/schema.(*Schema).buildMany2ManyRelation(0xc00000c3c0, 0xc0001fcab0, 0xc0003cb6c0, {0x9a9922, 0xc0003b7470})
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/schema/relationship.go:270  0xc25
gorm.io/gorm/schema.(*Schema).parseRelation(0xc00000c3c0, 0xc0003cb6c0)
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/schema/relationship.go:79  0x31f
gorm.io/gorm/schema.ParseWithSpecialTableName({0x9ab3c0, 0xc0000de580}, 0xc0003b74d0, {0xb35250, 0xc0003b7470}, {0x0, 0x0})
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/schema/schema.go:275  0x2105
gorm.io/gorm.(*Statement).ParseWithSpecialTableName(0xc0003ca540, {0x9ab3c0, 0xc0000de580}, {0x0, 0x203000})
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/statement.go:463  0x67
gorm.io/gorm.(*Statement).Parse(...)
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/statement.go:459
gorm.io/gorm/migrator.Migrator.ReorderModels.func1({0x9ab3c0, 0xc0000de580}, 0x1)
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/migrator/migrator.go:702  0x179
gorm.io/gorm/migrator.Migrator.ReorderModels({{0x60, 0xc0003b77a0, {0xb37360, 0xc0003b77d0}}}, {0xc0003d8460, 0x1, 0xa51940}, 0x1)
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/migrator/migrator.go:765  0x630
gorm.io/gorm/migrator.Migrator.AutoMigrate({{0x0, 0xc0003b77a0, {0xb37360, 0xc0003b77d0}}}, {0xc0003d8460, 0x0, 0x0})
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/migrator/migrator.go:90  0x6d
gorm.io/gorm.(*DB).AutoMigrate(0xb371a8, {0xc0003d8460, 0x1, 0x1})
        /home/nero/go/pkg/mod/gorm.io/gorm@v1.22.3/migrator.go:26  0x43
SMS-Go/models.ConnectDatabase()
        /home/nero/go/src/SMS-Go/models/setup.go:17  0x111
main.main()
        /home/nero/go/src/SMS-Go/main.go:13  0x27
exit status 2

Here are my models and the controller that is being read: trigger_controller.go:


/controllers/trigger_controller.go

package controllers

import (
    "SMS-Go/models"
    "net/http"
    "time"

    "github.com/gin-gonic/gin"
    uuid "github.com/nu7hatch/gouuid"
)

type MessageInput struct {
    TeamID  int    `json:"team_id" binding:"required"`
    Title   string `json:"title" binding:"required"`
    Content string `json:"content" binding:"required"`
}

// type Response struct {
//  TeamID string `json:"team_id"`
//  Sms    Sms    `json:"sms"`
//  Email  Email  `json:"email"`
// }
// type Sms struct {
//  ID      string   `json:"id"`
//  Mobiles []string `json:"mobiles"`
//  Content string   `json:"content"`
//  SentAt  string   `json:"sent_at"`
// }
// type Email struct {
//  ID      string   `json:"id"`
//  Emails  []string `json:"emails"`
//  Title   string   `json:"title"`
//  Content string   `json:"content"`
//  SentAt  string   `json:"sent_at"`
// }

func Notification(c *gin.Context) {
    var input MessageInput //input validation
    if err := c.ShouldBindJSON(&input); err != nil {
        c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
        return
    }
    u1, err := uuid.NewV4()
    _ = err
    message := models.Message{TeamID: input.TeamID, Title: input.Title, Content: input.Content}
    models.DB.Create(&message)
    mob := models.DB.Raw(`SELECT "developers"."mobile" FROM "developers" INNER JOIN "developer_teams" ON "developers"."id" = "developer_teams"."developer_id" WHERE "developer_teams"."team_id"`)
    mail := models.DB.Raw(`SELECT "developers"."email" FROM "developers" INNER JOIN "developer_teams" ON "developers"."id" = "developer_teams"."developer_id" WHERE "developer_teams"."team_id"`)

    c.JSON(http.StatusOK, gin.H{
        "team_id": input.TeamID,
        "sms": gin.H{
            "id":      u1,
            "mobiles": mob,
            "content": input.Content,
            "sent_at": time.Now(),
        },
        "email": gin.H{
            "id":      u1,
            "emails":  mail,
            "title":   input.Title,
            "content": input.Content,
            "sent_at": time.Now(),
        },
    },
    )

}

team.go:

/models/team.go

package models

import "gorm.io/gorm"

type Team struct {
    gorm.Model
    ID       uint   `json:"id" gorm:"primary_key"`
    Name     string `json:"name"`
    Dept     string `json:"dept_name"`
    Messages []Message
}

developer.go:

/models/developer.go

package models

import "gorm.io/gorm"

type Developer struct {
    gorm.Model
    ID         uint        `json:"id" gorm:"primary_key"`
    Full_name  string      `json:"full_name"`
    Email      string      `json:"email"`
    Mobile     string      `json:"mobile"`
    Developers []Developer `gorm:"many2many:developer_teams"`
}

message.go:

/models/message.go

package models

import "gorm.io/gorm"

type Message struct {
    gorm.Model
    ID      uint   `json:"id" gorm:"primary_key"`
    TeamID  int    `json:"team_id"`
    Title   string `json:"title"`
    Content string `json:"content"`
    Team    Team
}

I'm trying to make it such that when you enter the input fields as JSON in trigger_notification, it sends back a JSON response that shows all the developers that are under a specific team via the mobile and email objects. The response should look something like this:

{
    team_id: "team_id",
    sms: {
        id: "ARANDOMID",
        mobiles: ["numer1","number2"]
        content: "the content of this message",
        sent_at: "18:54:34 IST 2021"
    },
    email: {
        id: "ARANDOMID",
        emails: ["[email protected]", "[email protected]"]
        title: "Used in emails for title",
        content: "the content of this message",
        sent_at: "18:54:34 IST 2021"
    }

setup.go:

package models

import (
    "gorm.io/driver/sqlite"
    "gorm.io/gorm"
)

var DB *gorm.DB

func ConnectDatabase() {
    database, err := gorm.Open(sqlite.Open("sms-go.db"), &gorm.Config{})

    if err != nil {
        panic("Failure to connect to database")
    }

    database.AutoMigrate(&Developer{})
    database.AutoMigrate(&Message{})
    database.AutoMigrate(&Team{})

    DB = database
}

CodePudding user response：

For self-referential many2many relationship you need to use a field name that is different from the model's name, for example:

type Developer struct {
    gorm.Model
    ID        uint        `json:"id" gorm:"primary_key"`
    Full_name string      `json:"full_name"`
    Email     string      `json:"email"`
    Mobile    string      `json:"mobile"`

    // Change `Developers []Developer` to:
    DevTeam []Developer   `gorm:"many2many:developer_teams"`
}

See gorm.io docs: Self-Referential Many2Many.