package api import ( "context" "encoding/json" "net/http" "github.com/mediocregopher/mediocre-go-lib/v2/mlog" ) type loggerCtxKey int func setRequestLogger(r *http.Request, logger *mlog.Logger) *http.Request { ctx := r.Context() ctx = context.WithValue(ctx, loggerCtxKey(0), logger) return r.WithContext(ctx) } func getRequestLogger(r *http.Request) *mlog.Logger { ctx := r.Context() logger, _ := ctx.Value(loggerCtxKey(0)).(*mlog.Logger) if logger == nil { logger = mlog.Null } return logger } func jsonResult(rw http.ResponseWriter, r *http.Request, v interface{}) { b, err := json.Marshal(v) if err != nil { internalServerError(rw, r, err) return } b = append(b, '\n') rw.Header().Set("Content-Type", "application/json") rw.Write(b) } func badRequest(rw http.ResponseWriter, r *http.Request, err error) { getRequestLogger(r).Warn(r.Context(), "bad request", err) rw.WriteHeader(400) jsonResult(rw, r, struct { Error string `json:"error"` }{ Error: err.Error(), }) } func internalServerError(rw http.ResponseWriter, r *http.Request, err error) { getRequestLogger(r).Error(r.Context(), "internal server error", err) rw.WriteHeader(500) jsonResult(rw, r, struct { Error string `json:"error"` }{ Error: "internal server error", }) }