requestlog_test.go

package handlers

import (
	"bytes"
	"fmt"
	"log"
	"net/http"
	"net/http/httptest"
	"regexp"
	"strings"
	"testing"
)

var (
	validLog = regexp.MustCompile(`(\d.\d.\d.\d) - - \[(\d{2}[/]\d{2}[/]\d{4}:\d{2}:\d{2}:\d{2} [-+]\d{4})\]\s"GET\s.*\sHTTP/1.1"\s200`)
)

func TestLogHandler(t *testing.T) {
	expected := "Hello client"

	// Capture logging
	var b bytes.Buffer
	logger := log.New(&b, "", 0)

	fn := func(w http.ResponseWriter, r *http.Request) {
		fmt.Fprintln(w, expected)
	}

	h := RequestLogHandler(http.HandlerFunc(fn), logger)

	req, err := http.NewRequest("GET", "http://example.com/foo", nil)
	if err != nil {
		t.Fatal(err)
	}

	// Set a request address for the test
	raddr := "127.0.0.1"
	req.Header.Set("X-Forwarded-For", raddr)

	w := httptest.NewRecorder()
	h.ServeHTTP(w, req)

	if w.Code != http.StatusOK {
		t.Errorf("%d != %d", w.Code, http.StatusOK)
	}

	body := strings.TrimSpace(w.Body.String())
	if body != expected {
		t.Errorf("%s != %s", body, expected)
	}

	messages := strings.FieldsFunc(b.String(), func(c rune) bool {
		return c == '\n'
	})

	if len(messages) != 1 {
		t.Fatalf("Expected %d messages but got %d: %q", 1, len(messages), messages)
	}

	if !validLog.MatchString(messages[0]) {
		t.Errorf("%q not valid log message format", messages[0])
	}
}