AdGuardHome/internal/aghhttp/aghhttp.go
Ainar Garipov 757ddb06f8 Pull request 1839: 5716-write-json
Updates #5716.

Squashed commit of the following:

commit 8cf7c4f404fffb646c9df8643924eb8dc1d8f49d
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Wed Apr 19 18:09:35 2023 +0300

    aghhttp: write json properly
2023-04-19 18:15:17 +03:00

83 lines
2.6 KiB
Go

// Package aghhttp provides some common methods to work with HTTP.
package aghhttp
import (
"encoding/json"
"fmt"
"io"
"net/http"
"github.com/AdguardTeam/AdGuardHome/internal/version"
"github.com/AdguardTeam/golibs/httphdr"
"github.com/AdguardTeam/golibs/log"
)
// HTTP scheme constants.
const (
SchemeHTTP = "http"
SchemeHTTPS = "https"
)
// RegisterFunc is the function that sets the handler to handle the URL for the
// method.
//
// TODO(e.burkov, a.garipov): Get rid of it.
type RegisterFunc func(method, url string, handler http.HandlerFunc)
// OK responds with word OK.
func OK(w http.ResponseWriter) {
if _, err := io.WriteString(w, "OK\n"); err != nil {
log.Error("couldn't write body: %s", err)
}
}
// Error writes formatted message to w and also logs it.
func Error(r *http.Request, w http.ResponseWriter, code int, format string, args ...any) {
text := fmt.Sprintf(format, args...)
log.Error("%s %s %s: %s", r.Method, r.Host, r.URL, text)
http.Error(w, text, code)
}
// UserAgent returns the ID of the service as a User-Agent string. It can also
// be used as the value of the Server HTTP header.
func UserAgent() (ua string) {
return fmt.Sprintf("AdGuardHome/%s", version.Version())
}
// textPlainDeprMsg is the message returned to API users when they try to use
// an API that used to accept "text/plain" but doesn't anymore.
const textPlainDeprMsg = `using this api with the text/plain content-type is deprecated; ` +
`use application/json`
// WriteTextPlainDeprecated responds to the request with a message about
// deprecation and removal of a plain-text API if the request is made with the
// "text/plain" content-type.
func WriteTextPlainDeprecated(w http.ResponseWriter, r *http.Request) (isPlainText bool) {
if r.Header.Get(httphdr.ContentType) != HdrValTextPlain {
return false
}
Error(r, w, http.StatusUnsupportedMediaType, textPlainDeprMsg)
return true
}
// WriteJSONResponse sets the content-type header in w.Header() to
// "application/json", writes a header with a "200 OK" status, encodes resp to
// w, calls [Error] on any returned error, and returns it as well.
func WriteJSONResponse(w http.ResponseWriter, r *http.Request, resp any) (err error) {
return WriteJSONResponseCode(w, r, http.StatusOK, resp)
}
// WriteJSONResponseCode is like [WriteJSONResponse] but adds the ability to
// redefine the status code.
func WriteJSONResponseCode(w http.ResponseWriter, r *http.Request, code int, resp any) (err error) {
w.Header().Set(httphdr.ContentType, HdrValApplicationJSON)
w.WriteHeader(code)
err = json.NewEncoder(w).Encode(resp)
if err != nil {
Error(r, w, http.StatusInternalServerError, "encoding resp: %s", err)
}
return err
}