Adds a logger

logger.go

@@ -0,0 +1,67 @@
+package narco
+
+import (
+	"log"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/codemodus/chain"
+	"github.com/pivotal-golang/bytefmt"
+	"golang.org/x/net/context"
+
+	"net/http"
+)
+
+type Logger struct {
+	//may want a level based logger
+	*log.Logger
+}
+
+// to make the logger accessible for modification
+func NewLogger() *Logger {
+	return &Logger{log.New(os.Stdout, "[narco] ", 0)}
+}
+
+type FooResponseWriter struct {
+	header http.Header
+}
+
+func (f *FooResponseWriter) Header() http.Header {
+	return f.header
+}
+
+func (f *FooResponseWriter) WriteHeader(status int) {
+}
+
+func (f *FooResponseWriter) Write(b []byte) (int, error) {
+	return len(b), nil
+}
+
+func (l *Logger) Wrap() func(chain.Handler) chain.Handler {
+	return func(other chain.Handler) chain.Handler {
+		return chain.HandlerFunc(func(ctx context.Context, h http.ResponseWriter, r *http.Request) {
+			start := time.Now()
+			uAgentList, ok := r.Header["User-Agent"]
+			var uAgent string
+			if ok == false {
+				uAgent = "<unknown>"
+			} else {
+				uAgent = strings.Join(uAgentList, "; ")
+			}
+
+			l.Printf("Requested %s on %s from %s (User-Agent: %s)", r.Method, r.URL.Path, r.RemoteAddr, uAgent)
+
+			//wrap the request with our own interface
+			hh := WrapResponseWritter(h)
+
+			other.ServeHTTPContext(ctx, hh, r)
+
+			l.Printf("returned %d: %s, size: %s in %s",
+				hh.Status(),
+				http.StatusText(hh.Status()),
+				bytefmt.ByteSize(uint64(hh.Size())),
+				time.Since(start))
+		})
+	}
+}