GORM database colum with json data - postgresql

Question

I am trying to write an email service, where I want to store some data related to email into a Postgres DB using gorm. I have a field which needs to be stored as a JSON blob, which in request passed as a JSON object. When I am trying to migrate, it errors keep saying unsupported type map. When manually add the DB, then run gorm, it doesn't write the row to the database.
I have seen some example where it's using postgres.Json as field types, but I want the field loaded from the request as map[string]string.
// Email : Base with injected fields `UUID`, `CreatedAt`, `UpdatedAt`
type Email struct {
gorm.Model
Status string `grom:"type:varchar(32);not null"`
TemplateID string `grom:"type:varchar(256)"`
ToEmai string `grom:"type:varchar(256);not null"`
FromEmail string `grom:"type:varchar(256);not null"`
ToName string `grom:"type:varchar(256);not null"`
FromName string `grom:"type:varchar(256);not null"`
Subject string `grom:"type:varchar(256)"`
Message string `grom:"type:varchar"`
DynamicData *map[string]string `grom:"type:json"`
}
this is my model.
then I do a gin request:
// SendEmail : sends an email
func SendEmail(c *gin.Context) {
body, err := ioutil.ReadAll(c.Request.Body)
if err != nil {
log.Error("Error reading request body to get rate estimates")
}
var newEmail = models.Email{
Status: "PENDING",
}
jsonErr := json.Unmarshal(body, &newEmail)
if jsonErr != nil {
log.Error(jsonErr)
}
database.DB.Create(&newEmail)
defer c.Request.Body.Close()
err = newEmail.SendSendgridEmail()
if err != nil {
c.JSON(http.StatusBadRequest, err)
} else {
c.JSON(http.StatusOK, "Successfully sent email")
}
}
which then looks into this function
func (e Email) dynamicTemplateEmailBody() []byte {
newMail := mail.NewV3Mail()
emailFrom := mail.NewEmail(e.FromName, e.FromEmail)
newMail.SetFrom(emailFrom)
newMail.SetTemplateID(e.TemplateID)
p := mail.NewPersonalization()
tos := []*mail.Email{
mail.NewEmail(e.ToName, e.ToEmai),
}
p.AddTos(tos...)
if e.DynamicData != nil {
for key, value := range *e.DynamicData {
log.Infof("%s %s", key, value)
p.SetDynamicTemplateData(key, value)
}
}
newMail.AddPersonalizations(p)
return mail.GetRequestBody(newMail)
}
I would like to be able to run DB.AutoMigrate(&models.Email{}) and automatically migrate the objects, or and when I make a request to the endpoint, the row gets added to my email table.