Move SignIn page rendering to app pkg

pkg/app/sign_in_page.go

@@ -0,0 +1,66 @@
+package app
+
+import (
+	"html/template"
+	"net/http"
+
+	"github.com/oauth2-proxy/oauth2-proxy/v7/pkg/logger"
+)
+
+// SignInPage is used to render sign-in pages.
+type SignInPage struct {
+	// Template is the sign-in page HTML template.
+	Template *template.Template
+
+	// ErrorPage is used to render an error if there are problems with rendering the sign-in page.
+	ErrorPage *ErrorPage
+
+	// ProxyPrefix is the prefix under which OAuth2 Proxy pages are served.
+	ProxyPrefix string
+
+	// ProviderName is the name of the provider that should be displayed on the login button.
+	ProviderName string
+
+	// SignInMessage is the messge displayed above the login button.
+	SignInMessage string
+
+	// Footer is the footer to be displayed at the bottom of the page.
+	// If not set, a default footer will be used.
+	Footer string
+
+	// Version is the OAuth2 Proxy version to be used in the default footer.
+	Version string
+
+	// DisplayLoginForm determines whether or not the basic auth password form is displayed on the sign-in page.
+	DisplayLoginForm bool
+}
+
+// Render writes the sign-in page to the given response writer.
+// It uses the redirectURL to be able to set the final destination for the user post login.
+func (s *SignInPage) Render(rw http.ResponseWriter, redirectURL string) {
+	// We allow unescaped template.HTML since it is user configured options
+	/* #nosec G203 */
+	t := struct {
+		ProviderName  string
+		SignInMessage template.HTML
+		CustomLogin   bool
+		Redirect      string
+		Version       string
+		ProxyPrefix   string
+		Footer        template.HTML
+	}{
+		ProviderName:  s.ProviderName,
+		SignInMessage: template.HTML(s.SignInMessage),
+		CustomLogin:   s.DisplayLoginForm,
+		Redirect:      redirectURL,
+		Version:       s.Version,
+		ProxyPrefix:   s.ProxyPrefix,
+		Footer:        template.HTML(s.Footer),
+	}
+
+	err := s.Template.Execute(rw, t)
+	if err != nil {
+		logger.Printf("Error rendering sign-in template: %v", err)
+		s.ErrorPage.Render(rw, http.StatusInternalServerError, redirectURL, err.Error())
+	}
+}

pkg/app/sign_in_page_test.go

@@ -0,0 +1,61 @@
+package app
+
+import (
+	"html/template"
+	"io/ioutil"
+	"net/http/httptest"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("SignIn Page", func() {
+	var signInPage *SignInPage
+
+	BeforeEach(func() {
+		errorTmpl, err := template.New("").Parse("{{.Title}}")
+		Expect(err).ToNot(HaveOccurred())
+		errorPage := &ErrorPage{
+			Template: errorTmpl,
+		}
+
+		tmpl, err := template.New("").Parse("{{.ProxyPrefix}} {{.ProviderName}} {{.SignInMessage}} {{.Footer}} {{.Version}} {{.Redirect}} {{.CustomLogin}}")
+		Expect(err).ToNot(HaveOccurred())
+
+		signInPage = &SignInPage{
+			Template:         tmpl,
+			ErrorPage:        errorPage,
+			ProxyPrefix:      "/prefix/",
+			ProviderName:     "My Provider",
+			SignInMessage:    "Sign In Here",
+			Footer:           "Custom Footer Text",
+			Version:          "v0.0.0-test",
+			DisplayLoginForm: true,
+		}
+	})
+
+	Context("Render", func() {
+		It("Writes the template to the response writer", func() {
+			recorder := httptest.NewRecorder()
+			signInPage.Render(recorder, "/redirect")
+
+			body, err := ioutil.ReadAll(recorder.Result().Body)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(string(body)).To(Equal("/prefix/ My Provider Sign In Here Custom Footer Text v0.0.0-test /redirect true"))
+		})
+
+		It("Writes an error if the template can't be rendered", func() {
+			// Overwrite the template with something bad
+			tmpl, err := template.New("").Parse("{{.Unknown}}")
+			Expect(err).ToNot(HaveOccurred())
+			signInPage.Template = tmpl
+
+			recorder := httptest.NewRecorder()
+			signInPage.Render(recorder, "/redirect")
+
+			body, err := ioutil.ReadAll(recorder.Result().Body)
+			Expect(err).ToNot(HaveOccurred())
+			Expect(string(body)).To(Equal("Internal Server Error"))
+		})
+	})
+})