Improve test coverage. (#8)

* Improve test coverage.
* Remove unused http status code argument from SignInPageMethod.
* Removed log package in internal packages.
* Add test to check https scheme is used for authorization url.
* Add unit tests for global logging package.

authenticate/authenticate_test.go

@@ -0,0 +1,129 @@
+package authenticate
+
+import (
+	"net/url"
+	"os"
+	"reflect"
+	"testing"
+	"time"
+)
+
+func testOptions() *Options {
+	redirectURL, _ := url.Parse("https://example.com/oauth2/callback")
+	return &Options{
+		ProxyRootDomains:   []string{"example.com"},
+		AllowedDomains:     []string{"example.com"},
+		RedirectURL:        redirectURL,
+		SharedKey:          "80ldlrU2d7w+wVpKNfevk6fmb8otEx6CqOfshj2LwhQ=",
+		ClientID:           "test-client-id",
+		ClientSecret:       "OromP1gurwGWjQPYb1nNgSxtbVB5NnLzX6z5WOKr0Yw=",
+		CookieSecret:       "OromP1gurwGWjQPYb1nNgSxtbVB5NnLzX6z5WOKr0Yw=",
+		CookieRefresh:      time.Duration(1) * time.Hour,
+		SessionLifetimeTTL: time.Duration(720) * time.Hour,
+		CookieExpire:       time.Duration(168) * time.Hour,
+	}
+}
+
+func TestOptions_Validate(t *testing.T) {
+	good := testOptions()
+	badRedirectURL := testOptions()
+	badRedirectURL.RedirectURL = nil
+	malformedRedirectURL := testOptions()
+	redirectURL, _ := url.Parse("https://example.com/oauth3/callback")
+	malformedRedirectURL.RedirectURL = redirectURL
+	emptyClientID := testOptions()
+	emptyClientID.ClientID = ""
+	emptyClientSecret := testOptions()
+	emptyClientSecret.ClientSecret = ""
+	allowedDomains := testOptions()
+	allowedDomains.AllowedDomains = nil
+	proxyRootDomains := testOptions()
+	proxyRootDomains.ProxyRootDomains = nil
+	emptyCookieSecret := testOptions()
+	emptyCookieSecret.CookieSecret = ""
+	invalidCookieSecret := testOptions()
+	invalidCookieSecret.CookieSecret = "OromP1gurwGWjQPYb1nNgSxtbVB5NnLzX6z5WOKr0Yw^"
+	shortCookieLength := testOptions()
+	shortCookieLength.CookieSecret = "gN3xnvfsAwfCXxnJorGLKUG4l2wC8sS8nfLMhcStPg=="
+	badSharedKey := testOptions()
+	badSharedKey.SharedKey = ""
+
+	tests := []struct {
+		name    string
+		o       *Options
+		wantErr bool
+	}{
+		{"minimum options", good, false},
+		{"nil options", &Options{}, true},
+		{"bad redirect  url", badRedirectURL, true},
+		{"malformed redirect url", malformedRedirectURL, true},
+		{"no cookie secret", emptyCookieSecret, true},
+		{"invalid cookie secret", invalidCookieSecret, true},
+		{"short cookie secret", shortCookieLength, true},
+		{"no shared secret", badSharedKey, true},
+		{"no client id", emptyClientID, true},
+		{"no client secret", emptyClientSecret, true},
+		{"empty allowed domains", allowedDomains, true},
+		{"empty root domains", proxyRootDomains, true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			o := tt.o
+			if err := o.Validate(); (err != nil) != tt.wantErr {
+				t.Errorf("Options.Validate() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}
+
+func TestOptionsFromEnvConfig(t *testing.T) {
+	tests := []struct {
+		name     string
+		want     *Options
+		envKey   string
+		envValue string
+		wantErr  bool
+	}{
+		{"good default, no env settings", defaultOptions, "", "", false},
+		{"bad url", nil, "REDIRECT_URL", "%.rjlw", true},
+		{"good duration", defaultOptions, "COOKIE_EXPIRE", "1m", false},
+		{"bad duration", nil, "COOKIE_EXPIRE", "1sm", true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if tt.envKey != "" {
+				os.Setenv(tt.envKey, tt.envValue)
+				defer os.Unsetenv(tt.envKey)
+			}
+			got, err := OptionsFromEnvConfig()
+			if (err != nil) != tt.wantErr {
+				t.Errorf("OptionsFromEnvConfig() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("OptionsFromEnvConfig() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
+
+func Test_dotPrependDomains(t *testing.T) {
+
+	tests := []struct {
+		name string
+		d    []string
+		want []string
+	}{
+		{"single domain", []string{"google.com"}, []string{".google.com"}},
+		{"multiple domain", []string{"google.com", "bing.com"}, []string{".google.com", ".bing.com"}},
+		{"empty", []string{""}, []string{""}},
+		{"nested subdomain", []string{"some.really.long.domain.com"}, []string{".some.really.long.domain.com"}},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := dotPrependDomains(tt.d); !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("dotPrependDomains() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}