Refactoring and add tests

- rename `header.go` to `bearer.go`
- simplify header / cookie fetching of bearer token value
- simplify `BearerToken` method
- increase tests

Signed-off-by: Evgeniy Kulikov <kim@nspcc.ru>

bearer_test.go

@@ -0,0 +1,139 @@
+package main
+
+import (
+	"encoding/base64"
+	"testing"
+
+	"github.com/nspcc-dev/neofs-api-go/pkg/owner"
+
+	"github.com/nspcc-dev/neofs-api-go/pkg/token"
+
+	"github.com/stretchr/testify/require"
+	"github.com/valyala/fasthttp"
+)
+
+func makeTestCookie(value []byte) *fasthttp.RequestHeader {
+	header := new(fasthttp.RequestHeader)
+	header.SetCookie(bearerToken, string(value))
+	return header
+}
+
+func makeTestHeader(value []byte) *fasthttp.RequestHeader {
+	header := new(fasthttp.RequestHeader)
+	if value != nil {
+		header.Set(fasthttp.HeaderAuthorization, bearerToken+" "+string(value))
+	}
+	return header
+}
+
+func Test_fromCookie(t *testing.T) {
+	cases := []struct {
+		name   string
+		actual []byte
+		expect []byte
+	}{
+		{name: "empty"},
+		{name: "normal", actual: []byte("TOKEN"), expect: []byte("TOKEN")},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			require.Equal(t, tt.expect, fromCookie(makeTestCookie(tt.actual)))
+		})
+	}
+}
+
+func Test_fromHeader(t *testing.T) {
+	cases := []struct {
+		name   string
+		actual []byte
+		expect []byte
+	}{
+		{name: "empty"},
+		{name: "normal", actual: []byte("TOKEN"), expect: []byte("TOKEN")},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			require.Equal(t, tt.expect, fromHeader(makeTestHeader(tt.actual)))
+		})
+	}
+}
+
+func TestBearerToken(t *testing.T) {
+	uid := owner.NewID()
+
+	tkn := new(token.BearerToken)
+	tkn.SetOwner(uid)
+
+	data, err := tkn.Marshal()
+
+	require.NoError(t, err)
+
+	t64 := base64.StdEncoding.EncodeToString(data)
+	require.NotEmpty(t, t64)
+
+	cases := []struct {
+		name string
+
+		cookie string
+		header string
+
+		error  string
+		expect *token.BearerToken
+	}{
+		{name: "empty"},
+
+		{name: "bad base64 header", header: "WRONG BASE64", error: "could not fetch marshaled from base64"},
+		{name: "bad base64 cookie", cookie: "WRONG BASE64", error: "could not fetch marshaled from base64"},
+
+		{name: "header token unmarshal error", header: "dGVzdAo=", error: "could not unmarshal bearer token"},
+		{name: "cookie token unmarshal error", cookie: "dGVzdAo=", error: "could not unmarshal bearer token"},
+
+		{
+			name:   "bad header and cookie",
+			header: "WRONG BASE64",
+			cookie: "dGVzdAo=",
+			error:  "could not unmarshal bearer token",
+		},
+
+		{
+			name:   "bad header, but good cookie",
+			header: "dGVzdAo=",
+			cookie: t64,
+			expect: tkn,
+		},
+
+		{name: "ok for header", header: t64, expect: tkn},
+		{name: "ok for cookie", cookie: t64, expect: tkn},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			ctx := makeTestRequest(tt.cookie, tt.header)
+			actual, err := BearerToken(ctx)
+
+			if tt.error == "" {
+				require.NoError(t, err)
+				require.Equal(t, tt.expect, actual)
+
+				return
+			}
+
+			require.Contains(t, err.Error(), tt.error)
+		})
+	}
+}
+
+func makeTestRequest(cookie, header string) *fasthttp.RequestCtx {
+	ctx := new(fasthttp.RequestCtx)
+
+	if cookie != "" {
+		ctx.Request.Header.SetCookie(bearerToken, cookie)
+	}
+
+	if header != "" {
+		ctx.Request.Header.Set(fasthttp.HeaderAuthorization, bearerToken+" "+header)
+	}
+	return ctx
+}