Create nested struct based on url query parameters - rest

Question

My goal is to get some filtered records from database. Filtration is based on a struct which depends on another struct:
type Group struct {
ID primitive.ObjectID
Name string
}
type Role struct {
ID primitive.ObjectID
Name string
Description string
Groups []*group.Group
}
I create an object of Role struct from URL query parameters:
var roleWP Role
if r.URL.Query().Has("name") {
name := r.URL.Query().Get("name")
roleWP.Name = name
}
if r.URL.Query().Has("description") {
description := r.URL.Query().Get("description")
roleWP.Description = description
}
if r.URL.Query().Has("groups") {
//How would look groups parameter?
}
Filling name and description fields of Role struct is pretty simple. The whole url would be: myhost/roles?name=rolename&description=roledescription
But how would look url if I want to pass data for Group struct? Is it possible to pass data as a json object in query parameter? Also, I want to mention that groups field in Role is an array. My ideal dummy url would look like: myhost/roles?name=rolename&description=roledescription&groups={name:groupname1}&groups={name:groupname2}

Answer 1

Loop through the groups, split on :, create group and append to slice:
roleWP := Role{
Name: r.FormValue("name"),
Description: r.FormValue("description"),
}
for _, g := range r.Form["groups"] {
g = strings.TrimPrefix(g, "{")
g = strings.TrimSuffix(g, "}")
i := strings.Index(g, ":")
if i < 0 {
// handle error
}
roleWP.Groups = append(roleWP.Groups, &Group{g[:i], g[i+1:]})
}
Here's how to use JSON instead of OP's ideal format:
roleWP := Role{
Name: r.FormValue("name"),
Description: r.FormValue("description"),
}
for _, s := range r.Form["groups"] {
var g Group
err := json.Unmarshal([]byte(s), &v)
if err != nil {
// handle error
}
roleWP.Groups = append(roleWP.Groups, &g)
}