Cannot use context bind on a struct with "primitive.ObjectID"

[norx85]

Issue Description

It's impossible to bind the body of a request on a struct with primitive.ObjectID from the official mongodb mongo-driver

Expected behaviour

The string value of the id correctly mapped to primitive.ObjectID and no errors, as it was on older releases (this problem happens to me after an upgrade to v4.1.17)

Actual behaviour

It gives this error:

code=400, message=unknown type, internal=unknown type

Steps to reproduce

Just bind to a struct with a primitive.ObjectID

Working code to debug

import (
	"github.com/labstack/echo"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/bson/primitive"
)

type User struct {
	ID                 primitive.ObjectID `bson:"_id,omitempty" json:"_id,omitempty"`
        ...
}

func handleUpdate(c echo.Context) error {
    item := new(User)
    err := c.Bind(item)
    if err != nil {
        log.Println(err.Error())
    }
    ...
}

Version/commit

v4.1.17

[pierremarsotlyon1]

Up !
Same problem

[iambenkay]

Hy @pierremarsotlyon1 and @norx85

If you have worked with a version of echo that does not have this issue could you also tell the version?

[pierremarsotlyon1]

Hi @iambenkay

I downgrade echo version to v3.3.10-dev.
Issue seems fixed.

I have this issue with echo version v4.1.17

[iambenkay]

@pierremarsotlyon1 I can't seem to recreate this issue using v4.1.17
works perfectly.

here is a snippet https://repl.it/@iambenkay/Golang-Mongo-ID-bug

If possible tweak this to recreate the issue you're facing so the community can help

[pierremarsotlyon1]

You can reproduce with this snippet : https://repl.it/@PierreMarsot/Golang-Mongo-ID-bug
In fact, it's when we have a param in url

[iambenkay]

You need to add the param tag to the struct field in order for it to be parsed as a query param. Here's a snippet

type User struct {
  ID primitive.ObjectID `param:"id,omitempty"`
}

the param type helps echo serialize the parameter from the url to the struct field.

[pierremarsotlyon1]

With version 3, we don't need to do that

My struct :

type User struct {
	Id       primitive.ObjectID `json:"_id" bson:"_id,omitempty"`
}

My url :
api.PUT("/:id", userController.Update)

I get my id param like this :
idUserToUpdate := c.Param("id")

It is outside of my struct

Basically, i can put a param in my url and don't have it in my struct

[iambenkay]

okay. well that was a breaking change between v3 and v4. The bind was improved to automatically bind the url params, the request body and the query params into the struct. Although there have been a few issues on the restrictive nature of using one bind call for all the data units in the request and a PR is in the works at #1681 to separate the bind functions for each of them.

I think this feature is currently reserved for v5

[aldas]

@pierremarsotlyon1 if you want only to handle json POST, avoid c.Bind() and just decode body directly to struct

type User struct {
	Id       primitive.ObjectID `json:"_id" bson:"_id,omitempty"`
}
item := new(User)
if err := json.NewDecoder(c.Request().Body).Decode(item); err != nil {
	return err
}

and get path variable with c.Param("id").

[pierremarsotlyon1]

Sorry for delay
Ok thanks @aldas ! :)