Description
Gin does not support negotiation of the protobuf MIME type. As of 1.9.1, only [json, html, xml, yaml, toml] are supported.
Relevant source: https://github.com/gin-gonic/gin/blob/v1.9.1/context.go#L1116
How to reproduce
package main
import (
"github.com/gin-gonic/gin"
"github.com/gin-gonic/gin/binding"
"google.golang.org/protobuf/types/known/structpb"
)
func main() {
g := gin.Default()
testData, _ := structpb.NewStruct(map[string]interface{}{
"key": "value",
})
g.GET("/negotiate", func(c *gin.Context) {
c.Negotiate(200, gin.Negotiate{
Offered: []string{
binding.MIMEJSON,
binding.MIMEPROTOBUF,
},
Data: testData,
})
})
g.Run(":8080")
}
Expectations
$ curl -H 'Accept: application/x-protobuf' localhost:8080/negotiate
<binary protobuf encoding>
Actual result
$ curl -v -H 'Accept: application/x-protobuf' localhost:8080/negotiate
* Trying 127.0.0.1:8080...
* Connected to localhost (127.0.0.1) port 8080 (#0)
> GET /negotiate HTTP/1.1
> Host: localhost:8080
> User-Agent: curl/7.88.1
> Accept: application/x-protobuf
>
< HTTP/1.1 406 Not Acceptable
< Date: Tue, 12 Dec 2023 19:04:22 GMT
< Content-Length: 0
<
* Connection #0 to host localhost left intact
Environment
- go version: 1.21.1
- gin version (or commit ref): 1.9.1 (latest)
- operating system: Debian Bookworm
Comment From: kkoehler
I've created a pull request for that. see link
Comment From: kkoehler
The following sample works with the pull request
package main
import (
"github.com/gin-gonic/gin"
"github.com/gin-gonic/gin/binding"
"google.golang.org/protobuf/types/known/structpb"
)
func main() {
g := gin.Default()
testData, _ := structpb.NewStruct(map[string]interface{}{
"key": "value",
})
negotiate := gin.NewNegotiate([]string{
binding.MIMEJSON,
binding.MIMEPROTOBUF,
})
g.GET("/negotiate", func(c *gin.Context) {
c.Negotiate(200, negotiate.WithData(testData))
})
g.Run(":8080")
}