feat(logger): implement a logger middleware

This commit is contained in:
Julien Dessaux 2024-10-01 08:47:32 +02:00
parent 4ff490806c
commit 2cdbc4e782
Signed by: adyxax
GPG key ID: F92E51B86E07177E
4 changed files with 117 additions and 1 deletions

View file

@ -14,6 +14,7 @@ import (
"time" "time"
"git.adyxax.org/adyxax/tfstated/pkg/database" "git.adyxax.org/adyxax/tfstated/pkg/database"
"git.adyxax.org/adyxax/tfstated/pkg/logger"
) )
type Config struct { type Config struct {
@ -49,7 +50,7 @@ func run(
httpServer := &http.Server{ httpServer := &http.Server{
Addr: net.JoinHostPort(config.Host, config.Port), Addr: net.JoinHostPort(config.Host, config.Port),
Handler: mux, Handler: logger.Middleware(mux),
} }
go func() { go func() {
log.Printf("listening on %s\n", httpServer.Addr) log.Printf("listening on %s\n", httpServer.Addr)

View file

@ -11,6 +11,7 @@ func addRoutes(
db *database.DB, db *database.DB,
) { ) {
mux.Handle("GET /healthz", handleHealthz()) mux.Handle("GET /healthz", handleHealthz())
mux.Handle("GET /", handleGet(db)) mux.Handle("GET /", handleGet(db))
mux.Handle("POST /", handlePost(db)) mux.Handle("POST /", handlePost(db))
} }

46
pkg/logger/body_writer.go Normal file
View file

@ -0,0 +1,46 @@
package logger
import (
"bufio"
"errors"
"net"
"net/http"
)
type bodyWriter struct {
http.ResponseWriter
status int
}
func newBodyWriter(writer http.ResponseWriter) *bodyWriter {
return &bodyWriter{
ResponseWriter: writer,
status: http.StatusNotImplemented,
}
}
// implements http.ResponseWriter
func (w *bodyWriter) Write(b []byte) (int, error) {
return w.ResponseWriter.Write(b)
}
// implements http.ResponseWriter
func (w *bodyWriter) WriteHeader(code int) {
w.status = code
w.ResponseWriter.WriteHeader(code)
}
// implements http.Flusher
func (w *bodyWriter) Flush() {
if f, ok := w.ResponseWriter.(http.Flusher); ok {
f.Flush()
}
}
// implements http.Hijacker
func (w *bodyWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
if hi, ok := w.ResponseWriter.(http.Hijacker); ok {
return hi.Hijack()
}
return nil, nil, errors.New("Hijack not supported")
}

68
pkg/logger/middleware.go Normal file
View file

@ -0,0 +1,68 @@
package logger
import (
"log/slog"
"net/http"
"runtime/debug"
"strconv"
"time"
)
func Middleware(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
if r.Method == "GET" && r.URL.Path == "/healthz" {
next.ServeHTTP(w, r)
return
}
defer func() {
if err := recover(); err != nil {
w.WriteHeader(http.StatusInternalServerError)
slog.Error(
"panic",
"err", err,
"trace", string(debug.Stack()),
)
}
}()
start := time.Now()
path := r.URL.Path
query := r.URL.RawQuery
bw := newBodyWriter(w)
next.ServeHTTP(bw, r)
end := time.Now()
requestAttributes := []slog.Attr{
slog.Time("time", start.UTC()),
slog.String("method", r.Method),
slog.String("host", r.Host),
slog.String("path", path),
slog.String("query", query),
slog.String("ip", r.RemoteAddr),
}
responseAttributes := []slog.Attr{
slog.Time("time", end.UTC()),
slog.Duration("latency", end.Sub(start)),
slog.Int("status", bw.status),
}
attributes := []slog.Attr{
{
Key: "request",
Value: slog.GroupValue(requestAttributes...),
},
{
Key: "response",
Value: slog.GroupValue(responseAttributes...),
},
}
level := slog.LevelInfo
if bw.status >= http.StatusInternalServerError {
level = slog.LevelError
} else if bw.status >= http.StatusBadRequest && bw.status < http.StatusInternalServerError {
level = slog.LevelWarn
}
slog.LogAttrs(r.Context(), level, strconv.Itoa(bw.status)+": "+http.StatusText(bw.status), attributes...)
})
}