在SPA中创建对象时，如何防止重复的ID？ 还是应该留在数据库？

Question

I have a react app that fetches data from golang api which queries data from postgres database. One of my models is deeply nested JSON so I used JSONB datatype in postgres.

CREATE table rules (
    id serial primary key,
    rule jsonb
);

In golang, I have the structure

type Rule struct {
    ID int `json:"id"`
    Name string `json:"name"`
    ...succeeding fields are deeply nested data
}

And in the SPA I have the model

interface Rule {
    id number
    name string
    ....same as from the golang api model
}

To create a new Rule object in the SPA, I assign 0 to id. The newly created rule is sent to golang rest api. Then in the api, I first ask the postgres database for the next value for the serial id (using POSTGRES nextval), assign that acquired id into the Rule struct ID field,

nextValidId := <result of nextval>
rule.ID = nextValidId

JSON marshal the rule object then insert to db

ruleBytes, _ := json.Marshal(rule)
INSERT INTO rules_table VALUES (<nextValidId>, <ruleBytes>);

This way I avoided duplicate ids which may happen if an SPA is handling the Id generation. However, I find my method somewhat complicated already. I know I can generate ids from SPA too but how do I avoid duplicated ids without using the method I used above? or am I overthinking things?

Update1: I also thought about adding another Rule struct in golang without the ID field so that I don't have to use nextval just to put the id inside the JSON, but is it a good programming design to have multiple models for inserting and retrieving from db and another model for response to the SPA?

Answer 1

Let the database generate the new id since that's exactly SERIAL types are for in PostgreSQL.

In golang, you can insert a new record and retrieve the generated id by using sql.DB.QueryRow(...) and .Scan() using an insert statement with a RETURNING clause, e.g.:

var newId int
query := "INSERT INTO rules (rule) VALUES ($1) RETURNING id"
err := db.QueryRow(query, newRule).Scan(&newId)
// TODO: check err
log.Printf("newId=%d", newId)