write-json.go

// Copyright (c) 2024, Roel Schut. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package serv

import (
	"encoding/json"
	"net/http"

	"github.com/go-pogo/errors"
)

const contentTypeJSON = "application/json"

// WriteJSON encodes v to JSON and writes it to w.
func WriteJSON(w http.ResponseWriter, v any) error {
	if v == nil {
		return nil
	}
	if m, ok := v.(json.Marshaler); ok {
		b, err := m.MarshalJSON()
		if err != nil {
			return errors.WithStack(err)
		}
		_, _ = w.Write(b)
	} else if err := json.NewEncoder(w).Encode(v); err != nil {
		return errors.WithStack(err)
	}

	w.Header().Set("Content-Type", contentTypeJSON)
	return nil
}

// WriteJSONError encodes error err to JSON and writes it to w.
func WriteJSONError(w http.ResponseWriter, err error) error {
	type Error struct {
		Error string `json:"error"`
	}
	if writeErr := WriteJSON(w, Error{err.Error()}); writeErr != nil {
		return errors.WithStack(writeErr)
	}

	w.WriteHeader(errors.GetStatusCodeOr(err, http.StatusInternalServerError))
	return nil
}