postgres, go-gorm - can't preload data - postgresql

Question

I am trying to preload some data when querying for a row on my postgresql with gorm
I have the following types defined in go with a belongs to association:
type MyObject struct {
ID uint `grom:"column:id" json:"id"`
Name string `gorm:"column:name" json:"name"`
OwnerID uint `gorm:"column:owner_id" json:"owner_id"`
Owner Owner `json:"owner"`
...
}
type Owner struct {
ID uint `gorm:"column:id" json:"id"`
Name string `gorm:"column:name" json:"name"`
Config json.RawMessage `gorm:"column:config" sql:"type:json" json:"config"`
Components []uint8 `gorm:"column:components;type:integer[]" json:"components"`
}
and the tables in the postgres db with a row as follows
my_schema.my_object
id | name | owner_id | ...
----|-----------|-----------|-----
0 | testobj | 0 | ...
my_schema.owner
id | name | config | components
----|-----------|-----------|-----------
0 | testowner | <jsonb> | {0,1,2,3}
I am running the following query with gorm:
object := &models.MyObject{}
result := ls.Table("my_schema.my_object").
Preload("Owner").
Where("id = ?", "0").
First(object)
but as a result, in object i get the following struct:
{"id": 0, "name": "testobj", "owner_id":0, "owner": {"id": 0, "name": "", "config": nil, "components": nil}}
I get no errors or warnings of any kind
the foreignkey relation was specified in the database creation sql script

Answer 1

I was able to achieve what I wanted by implementing the TableName() method for each of my models as such:
type MyObject struct {
ID uint `grom:"column:id" json:"id"`
OwnerID uint `gorm:"column:owner_id" json:"owner_id"`
Owner Owner `json:"owner"`
...
}
func (MyObject) TableName() {
return "my_schema.my_object"
}
type Owner struct {
ID uint `gorm:"column:id" json:"id"`
...
}
func (Owner) TableName() {
return "my_schema.owner"
}
Then, I can then use it in a query like the following:
myObject := &models.MyObject{}
result := ls.Model(myObject).
Where("id = ?", id). //assume any valid value for id
First(myObject).
Related(&myObject.Owner)
return myObject, processResult(result)
in the end, when making a request for MyObject to my server I get all the data of the related Owner object in the database:
$ curl "http://localhost:8080/api/objetcs/related/1" | jq // passing 1 as object id value in url params
{
"id": "1", // taken from UrlParam
"name": "testobj",
"owner": {
"id": "1", // using foreign key owner_id
"name": "testowner",
"config": configJson // json object taken from row in my_schema.owner table in the DB
}
}
}