chrly/http/http.go
2020-04-20 15:34:52 +03:00

139 lines
3.4 KiB
Go

package http
import (
"context"
"encoding/json"
"net/http"
"os"
"os/signal"
"strings"
"github.com/gorilla/mux"
"github.com/mono83/slf"
"github.com/mono83/slf/wd"
"github.com/elyby/chrly/dispatcher"
)
type Emitter interface {
dispatcher.Emitter
}
func StartServer(server *http.Server, logger slf.Logger) {
done := make(chan bool, 1)
go func() {
logger.Info("Starting the server, HTTP on: :addr", wd.StringParam("addr", server.Addr))
if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
logger.Emergency("Error in main(): :err", wd.ErrParam(err))
}
close(done)
}()
go func() {
s := waitForExitSignal()
logger.Info("Got signal: :signal, starting graceful shutdown", wd.StringParam("signal", s.String()))
server.Shutdown(context.Background())
logger.Info("Graceful shutdown succeed, exiting", wd.StringParam("signal", s.String()))
close(done)
}()
<-done
}
func waitForExitSignal() os.Signal {
ch := make(chan os.Signal, 1)
signal.Notify(ch, os.Interrupt, os.Kill)
return <-ch
}
type loggingResponseWriter struct {
http.ResponseWriter
statusCode int
}
func (lrw *loggingResponseWriter) WriteHeader(code int) {
lrw.statusCode = code
lrw.ResponseWriter.WriteHeader(code)
}
func CreateRequestEventsMiddleware(emitter Emitter, prefix string) mux.MiddlewareFunc {
beforeTopic := strings.Join([]string{prefix, "before_request"}, ":")
afterTopic := strings.Join([]string{prefix, "after_request"}, ":")
return func(handler http.Handler) http.Handler {
return http.HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
emitter.Emit(beforeTopic, req)
lrw := &loggingResponseWriter{
ResponseWriter: resp,
statusCode: http.StatusOK,
}
handler.ServeHTTP(lrw, req)
emitter.Emit(afterTopic, req, lrw.statusCode)
})
}
}
type Authenticator interface {
Authenticate(req *http.Request) error
}
func CreateAuthenticationMiddleware(checker Authenticator) mux.MiddlewareFunc {
return func(handler http.Handler) http.Handler {
return http.HandlerFunc(func(resp http.ResponseWriter, req *http.Request) {
err := checker.Authenticate(req)
if err != nil {
apiForbidden(resp, err.Error())
return
}
handler.ServeHTTP(resp, req)
})
}
}
func NotFoundHandler(response http.ResponseWriter, _ *http.Request) {
data, _ := json.Marshal(map[string]string{
"status": "404",
"message": "Not Found",
})
response.Header().Set("Content-Type", "application/json")
response.WriteHeader(http.StatusNotFound)
_, _ = response.Write(data)
}
func apiBadRequest(resp http.ResponseWriter, errorsPerField map[string][]string) {
resp.WriteHeader(http.StatusBadRequest)
resp.Header().Set("Content-Type", "application/json")
result, _ := json.Marshal(map[string]interface{}{
"errors": errorsPerField,
})
_, _ = resp.Write(result)
}
func apiForbidden(resp http.ResponseWriter, reason string) {
resp.WriteHeader(http.StatusForbidden)
resp.Header().Set("Content-Type", "application/json")
result, _ := json.Marshal(map[string]interface{}{
"error": reason,
})
_, _ = resp.Write(result)
}
func apiNotFound(resp http.ResponseWriter, reason string) {
resp.WriteHeader(http.StatusNotFound)
resp.Header().Set("Content-Type", "application/json")
result, _ := json.Marshal([]interface{}{
reason,
})
_, _ = resp.Write(result)
}
func apiServerError(resp http.ResponseWriter) {
resp.WriteHeader(http.StatusInternalServerError)
}