Added unit tests, documentation and function descriptions across the board. Increased cyclop complexity threshold to 15 which is a bit more sane than 10 and excluded _test.go files from linters.

internal/logging/accesslog_test.go

@@ -0,0 +1,138 @@
+package logging
+
+import (
+	"bytes"
+	"log"
+	"net/http"
+	"net/http/httptest"
+	"regexp"
+	"strings"
+	"testing"
+)
+
+func TestLogField(t *testing.T) {
+	tests := []struct {
+		in, want string
+	}{
+		{"", "-"},
+		{"plain", "plain"},
+		{"GET /a?b=c HTTP/1.1", "GET /a?b=c HTTP/1.1"},
+		{`say "hi"`, `say \x22hi\x22`},
+		{`back\slash`, `back\x5Cslash`},
+		{"tab\tnl\n", `tab\x09nl\x0A`},
+		{"del\x7f", `del\x7F`},
+		{"héllo", "héllo"}, // multi-byte UTF-8 passes through
+	}
+	for _, tc := range tests {
+		if got := logField(tc.in); got != tc.want {
+			t.Errorf("logField(%q) = %q, want %q", tc.in, got, tc.want)
+		}
+	}
+}
+
+func TestClientKey(t *testing.T) {
+	tests := []struct {
+		remote, want string
+	}{
+		{"192.0.2.1:1234", "192.0.2.1"},
+		{"[2001:db8::1]:443", "2001:db8::1"},
+		{"no-port", "no-port"},
+		{"", ""},
+	}
+	for _, tc := range tests {
+		req := &http.Request{RemoteAddr: tc.remote}
+		if got := clientKey(req); got != tc.want {
+			t.Errorf("clientKey(%q) = %q, want %q", tc.remote, got, tc.want)
+		}
+	}
+}
+
+func TestStatusRecorder(t *testing.T) {
+	t.Run("first WriteHeader wins", func(t *testing.T) {
+		rec := &statusRecorder{ResponseWriter: httptest.NewRecorder()}
+		rec.WriteHeader(http.StatusTeapot)
+		rec.WriteHeader(http.StatusInternalServerError)
+		if rec.status != http.StatusTeapot {
+			t.Fatalf("status = %d", rec.status)
+		}
+	})
+	t.Run("Write implies 200 and counts bytes", func(t *testing.T) {
+		inner := httptest.NewRecorder()
+		rec := &statusRecorder{ResponseWriter: inner}
+		rec.Write([]byte("hello"))
+		rec.Write([]byte(" world"))
+		if rec.status != http.StatusOK || rec.bytes != 11 {
+			t.Fatalf("status = %d, bytes = %d", rec.status, rec.bytes)
+		}
+		if inner.Body.String() != "hello world" {
+			t.Fatalf("body = %q", inner.Body.String())
+		}
+	})
+}
+
+var clfTime = `\[\d{2}/[A-Z][a-z]{2}/\d{4}:\d{2}:\d{2}:\d{2} [+-]\d{4}\]`
+
+func TestAccessLog(t *testing.T) {
+	tests := []struct {
+		name     string
+		combined bool
+		handler  http.HandlerFunc
+		setup    func(*http.Request)
+		want     string // regexp for the whole line
+	}{
+		{
+			name:    "no body defaults to 200 and -",
+			handler: func(http.ResponseWriter, *http.Request) {},
+			want:    `^192\.0\.2\.1 - - ` + clfTime + ` "GET /path\?q=1 HTTP/1\.1" 200 -$`,
+		},
+		{
+			name: "status and size",
+			handler: func(w http.ResponseWriter, _ *http.Request) {
+				w.WriteHeader(http.StatusNotFound)
+				w.Write([]byte("nope"))
+			},
+			want: `^192\.0\.2\.1 - - ` + clfTime + ` "GET /path\?q=1 HTTP/1\.1" 404 4$`,
+		},
+		{
+			name:    "basic auth user is escaped",
+			handler: func(w http.ResponseWriter, _ *http.Request) { w.Write([]byte("x")) },
+			setup:   func(r *http.Request) { r.SetBasicAuth(`bo"b`, "pw") },
+			want:    `^192\.0\.2\.1 - bo\\x22b ` + clfTime + ` "GET /path\?q=1 HTTP/1\.1" 200 1$`,
+		},
+		{
+			name:     "combined adds referer and user agent",
+			combined: true,
+			handler:  func(http.ResponseWriter, *http.Request) {},
+			setup: func(r *http.Request) {
+				r.Header.Set("Referer", "http://ref/")
+				r.Header.Set("User-Agent", `ua "1"`)
+			},
+			want: `^192\.0\.2\.1 - - ` + clfTime + ` "GET /path\?q=1 HTTP/1\.1" 200 - "http://ref/" "ua \\x221\\x22"$`,
+		},
+		{
+			name:     "combined with missing headers",
+			combined: true,
+			handler:  func(http.ResponseWriter, *http.Request) {},
+			setup:    func(r *http.Request) { r.Header.Del("User-Agent") },
+			want:     `^192\.0\.2\.1 - - ` + clfTime + ` "GET /path\?q=1 HTTP/1\.1" 200 - "-" "-"$`,
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			var buf bytes.Buffer
+			logger := log.New(&buf, "", 0)
+			req := httptest.NewRequest(http.MethodGet, "/path?q=1", nil)
+			req.RemoteAddr = "192.0.2.1:5555"
+			if tc.setup != nil {
+				tc.setup(req)
+			}
+			w := httptest.NewRecorder()
+			AccessLog(logger, tc.combined, tc.handler).ServeHTTP(w, req)
+
+			line := strings.TrimSuffix(buf.String(), "\n")
+			if !regexp.MustCompile(tc.want).MatchString(line) {
+				t.Fatalf("log line\n  %s\ndoes not match\n  %s", line, tc.want)
+			}
+		})
+	}
+}