Replace Echo logger with slog. (#67)

* Replace Echo logger with slog.

pkg/middleware/log.go

@@ -1,20 +1,80 @@
 package middleware
 
 import (
-	"fmt"
+	"strconv"
+	"time"
 
 	"github.com/labstack/echo/v4"
+	"github.com/mikestefanello/pagoda/pkg/log"
 )
 
-// LogRequestID includes the request ID in all logs for the given request
-// This requires that middleware that includes the request ID first execute
-func LogRequestID() echo.MiddlewareFunc {
+// SetLogger initializes a logger for the current request and stores it in the context.
+// It's recommended to have this executed after Echo's RequestID() middleware because it will add
+// the request ID to the logger so that all log messages produced from this request have the
+// request ID in it. You can modify this code to include any other fields that you want to always
+// appear.
+func SetLogger() echo.MiddlewareFunc {
 	return func(next echo.HandlerFunc) echo.HandlerFunc {
-		return func(c echo.Context) error {
-			rID := c.Response().Header().Get(echo.HeaderXRequestID)
-			format := `{"time":"${time_rfc3339_nano}","id":"%s","level":"${level}","prefix":"${prefix}","file":"${short_file}","line":"${line}"}`
-			c.Logger().SetHeader(fmt.Sprintf(format, rID))
-			return next(c)
+		return func(ctx echo.Context) error {
+			// Include the request ID in the logger
+			rID := ctx.Response().Header().Get(echo.HeaderXRequestID)
+			logger := log.Ctx(ctx).With("request_id", rID)
+
+			// TODO include other fields you may want in all logs for this request
+			log.Set(ctx, logger)
+			return next(ctx)
+		}
+	}
+}
+
+// LogRequest logs the current request
+// Echo provides middleware similar to this, but we want to use our own logger
+func LogRequest() echo.MiddlewareFunc {
+	return func(next echo.HandlerFunc) echo.HandlerFunc {
+		return func(ctx echo.Context) (err error) {
+			req := ctx.Request()
+			res := ctx.Response()
+
+			// Track how long the request takes to complete
+			start := time.Now()
+			if err = next(ctx); err != nil {
+				ctx.Error(err)
+			}
+			stop := time.Now()
+
+			sub := log.Ctx(ctx).With(
+				"ip", ctx.RealIP(),
+				"host", req.Host,
+				"method", req.Method,
+				"path", func() string {
+					p := req.URL.Path
+					if p == "" {
+						p = "/"
+					}
+					return p
+				}(),
+				"referer", req.Referer(),
+				"status", res.Status,
+				"bytes_in", func() string {
+					cl := req.Header.Get(echo.HeaderContentLength)
+					if cl == "" {
+						cl = "0"
+					}
+					return cl
+				}(),
+				"bytes_out", strconv.FormatInt(res.Size, 10),
+				"latency", stop.Sub(start).String(),
+			)
+
+			// TODO is there a (better) way to log without a message?
+
+			if res.Status >= 500 {
+				sub.Error("")
+			} else {
+				sub.Info("")
+			}
+
+			return nil
 		}
 	}
 }