Change interface depending on if statement

Question

I'm using fiber and mongodb. Field "field" is needed to obtain certain data to unload the load on the database. If field "field" is empty, then needs to output all the data from the database to make work easier to frontend. I don't like this crutch. Is there a much better solution?

func GetUserById(c *fiber.Ctx) error {
    ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
    var userId = c.Params("userId")
    defer cancel()

    objId, _ := primitive.ObjectIDFromHex(userId)

    // Creates options for search.
    opts, err := search.GetOneOptions(c, models.UserModel{})
    if err != nil {
        return responses.Response(c, http.StatusBadRequest, err.Error())
    }

    if c.Query("field") != "" {
        var user models.UserModelOmitempty

        err = usersCollection.FindOne(ctx, bson.M{"_id": objId}, opts).Decode(&user)
        if err != nil {
            return responses.Response(c, http.StatusBadRequest, "user not found")
        }

        return responses.ResponseWithData(c, http.StatusOK, "success", user)
    } else {
        var user models.UserModel

        err = usersCollection.FindOne(ctx, bson.M{"_id": objId}, opts).Decode(&user)
        if err != nil {
            return responses.Response(c, http.StatusBadRequest, "user not found")
        }

        return responses.ResponseWithData(c, http.StatusOK, "success", user)
    }

}

models.UserModel

type UserModel struct {
    Id               primitive.ObjectID `json:"id" bson:"_id" query:"string"`
    Name             string             `json:"name" bson:"name" validate:"required" query:"string"`
    Email            string             `json:"email" bson:"email" validate:"required" query:"string"`
    Password         string             `json:"-" bson:"password" validate:"required"`
    CreatedAt        int64              `json:"createdAt" bson:"createdAt" query:"int"`
    Rights           string             `json:"rights" bson:"rights" query:"string"`
    PhotoUrl         string             `json:"photoUrl" bson:"photoUrl"`
    Sex              string             `json:"sex" bson:"sex" query:"string"`
    BirthDate        int64              `json:"birthDate" bson:"birthDate" query:"int"`
    Country          string             `json:"country" bson:"country" query:"string"`
    EmailSubscribe   bool               `json:"emailSubscribe" bson:"emailSubscribe" query:"bool"`
    AccountConfirmed bool               `json:"accountConfirmed" bson:"accountConfirmed" query:"bool"`
}

models.UserModelOmitempty

type UserModelOmitempty struct {
    Id               primitive.ObjectID `json:"id" bson:"_id" query:"string"`
    Name             string             `json:"name,omitempty" bson:"name" validate:"required" query:"string"`
    Email            string             `json:"email,omitempty" bson:"email" validate:"required" query:"string"`
    Password         string             `json:"-" bson:"password" validate:"required"`
    CreatedAt        int64              `json:"createdAt,omitempty" bson:"createdAt" query:"int"`
    Rights           string             `json:"rights,omitempty" bson:"rights" query:"string"`
    PhotoUrl         string             `json:"photoUrl,omitempty" bson:"photoUrl"`
    Sex              string             `json:"sex,omitempty" bson:"sex" query:"string"`
    BirthDate        int64              `json:"birthDate,omitempty" bson:"birthDate" query:"int"`
    Country          string             `json:"country,omitempty" bson:"country" query:"string"`
    EmailSubscribe   bool               `json:"emailSubscribe,omitempty" bson:"emailSubscribe" query:"bool"`
    AccountConfirmed bool               `json:"accountConfirmed,omitempty" bson:"accountConfirmed" query:"bool"`
}

Result in postman:

I'm assuming this snippet is part of a function or method. Where is the rest of it? I see code duplication so we can probably improve it, but a good review requires more context. — Mast
– Mast ♦, Commented Jun 26, 2022 at 9:00

muru · Accepted Answer · 2022-06-26 11:59:45Z

Since the types seem to be identical except for the JSON tags, you could use either models.UserModel or models.UserModelOmitempty for most of code, until the point where serialization comes into play, which will be when you call responses.Response(...) and then convert to the correct type:

var user 
err = usersCollection.FindOne(ctx, bson.M{"_id": objId}, opts).Decode(&user)
if err != nil {
    return responses.Response(c, http.StatusBadRequest, "user not found")
}
if c.Query("field") != "" {
    // No field specified, so omitting empty fields
    return responses.ResponseWithData(c, http.StatusOK, "success", models.UserModelOmitempty(user))
}
return responses.ResponseWithData(c, http.StatusOK, "success", user)

Boro8ey · Accepted Answer · 2022-06-26 12:36:42Z

Thanks @muru for giving me the idea. The result here:

Models.

type UserModel struct {
    Id               primitive.ObjectID `json:"id" bson:"_id" query:"string"`
    Name             string             `json:"name" bson:"name" validate:"required" query:"string"`
    Email            string             `json:"email" bson:"email" validate:"required" query:"string"`
    Password         string             `json:"-" bson:"password" validate:"required"`
    CreatedAt        *time.Time         `json:"createdAt" bson:"createdAt" query:"date"`
    Rights           string             `json:"rights" bson:"rights" query:"string"`
    PhotoUrl         string             `json:"photoUrl" bson:"photoUrl"`
    Sex              string             `json:"sex" bson:"sex" query:"string"`
    BirthDate        *time.Time         `json:"birthDate" bson:"birthDate" query:"date"`
    Country          string             `json:"country" bson:"country" query:"string"`
    EmailSubscribe   bool               `json:"emailSubscribe" bson:"emailSubscribe" query:"bool"`
    AccountConfirmed bool               `json:"accountConfirmed" bson:"accountConfirmed" query:"bool"`
}
type UserModelOmitempty struct {
    Id               primitive.ObjectID `json:"id" bson:"_id"`
    Name             string             `json:"name,omitempty"`
    Email            string             `json:"email,omitempty"`
    Password         string             `json:"-" bson:"password"`
    CreatedAt        *time.Time         `json:"createdAt,omitempty"`
    Rights           string             `json:"rights,omitempty"`
    PhotoUrl         string             `json:"photoUrl,omitempty"`
    Sex              string             `json:"sex,omitempty"`
    BirthDate        *time.Time         `json:"birthDate,omitempty"`
    Country          string             `json:"country,omitempty"`
    EmailSubscribe   bool               `json:"emailSubscribe,omitempty"`
    AccountConfirmed bool               `json:"accountConfirmed,omitempty"`
}

func (u *UserModel) ConvertToOmitempty() interface{} {
    return UserModelOmitempty{
        Id:               u.Id,
        Name:             u.Name,
        Email:            u.Email,
        CreatedAt:        u.CreatedAt,
        Rights:           u.Rights,
        PhotoUrl:         u.PhotoUrl,
        Sex:              u.Sex,
        BirthDate:        u.BirthDate,
        Country:          u.Country,
        EmailSubscribe:   u.EmailSubscribe,
        AccountConfirmed: u.AccountConfirmed,
    }
}

Controller.

func GetUserById(c *fiber.Ctx) error {
    ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
    var userId = c.Params("userId")
    var user models.UserModel
    defer cancel()

    objId, _ := primitive.ObjectIDFromHex(userId)

    // Creates options for search.
    opts, err := search.GetOneOptions(c, models.UserModel{})
    if err != nil {
        return responses.Response(c, http.StatusBadRequest, err.Error())
    }

    err = usersCollection.FindOne(ctx, bson.M{"_id": objId}, opts).Decode(&user)
    if err != nil {
        return responses.Response(c, http.StatusBadRequest, "user not found")
    }

    if c.Query("field") != "" {
        return responses.ResponseWithData(c, http.StatusOK, "success", user.ConvertToOmitempty())
    }

    return responses.ResponseWithData(c, http.StatusOK, "success", user)
}

```

Rather than post updated code as an answer, you should post a follow up question with a link back to this question. You should also read What to do when someone answers my question. — pacmaninbw
– pacmaninbw ♦, Commented Jun 26, 2022 at 13:49

Stack Exchange Network

Change interface depending on if statement

2 Answers 2

You must log in to answer this question.

Hot Network Questions

Change interface depending on if statement

2 Answers 2

You must log in to answer this question.

Related

Hot Network Questions