如何使用Google / jsonapi和echo框架返回有效的jsonapi响应

Question

The code bellow return a two concated JSON strings and a wrong content-type text/plain. Should be application/vnd.api+json

package main

import (
    "github.com/google/jsonapi"
    "github.com/labstack/echo"
    "net/http"
)

type Album struct {
    ID   int    `jsonapi:"primary,albums"`
    Name string `jsonapi:"attr,name"`
}

func main() {
    e := echo.New()
    e.GET("/", func(c echo.Context) error {
        jsonapi.MarshalManyPayload(c.Response(), albumList())
        return c.JSON(http.StatusOK, c.Response())
    })
    e.Logger.Fatal(e.Start(":1323"))
}

func albumList() []*Album {
    a1 := Album{123, "allbum1"}
    a2 := Album{456, "allbum2"}
    albums := []*Album{&a1, &a2}
    return albums
}

faulty output (two concated jsons). The first is a correct jsonapi structure and I think the second is related to echo-framework:

{
  "data": [
    {
      "type": "albums",
      "id": "123",
      "attributes": {
    "name": "allbum1"
      }
    },
    {
      "type": "albums",
      "id": "456",
      "attributes": {
    "name": "allbum2"
      }
    }
  ]
}
{
  "Writer": {},
  "Status": 200,
  "Size": 133,
  "Committed": true
}

This code fix the problem but is seems awkward. I have the feeling there is a better way to facilitate it using echo.

e.GET("/", func(c echo.Context) error {
    var b bytes.Buffer
    body := bufio.NewWriter(&b)
    err := jsonapi.MarshalManyPayload(body, albumList())
    if err != nil {
        fmt.Println(err)
    }
    body.Flush()
    return c.JSONBlob(http.StatusOK, b.Bytes())
})

Any idea?

Answer 1

You're code looks alright. However it can be simplified-

var b bytes.Buffer // you could use buffer pool here
err := jsonapi.MarshalManyPayload(&b, albumList())
if err != nil {
    return err
}
return c.JSONBlob(http.StatusOK, b.Bytes())

---

Following approaches for your thoughts:

Approach 1 -

c.Response().Header().Set(echo.HeaderContentType, jsonapi.MediaType)
c.Response().WriteHeader(http.StatusOK)
return jsonapi.MarshalManyPayload(c.Response(), albumList())

---

Approach 2 -

var b bytes.Buffer // you could use buffer pool here
err := jsonapi.MarshalManyPayload(&b, albumList())
if err != nil {
    return err
}
c.Response().Header().Set(echo.HeaderContentType, jsonapi.MediaType)
c.Response().WriteHeader(http.StatusOK)
_, err := b.WriteTo(c.Response())
return err