feat(coderd): add company logo when available for email notifications (#14935)

This PR aims to close #14253 

We keep the default behavior using the Coder logo if there's no logo
set.
Otherwise we want to use the logo based on the URL set in appearance.

---------

Co-authored-by: defelmnq <yvincent@coder.com>

coderd/notifications/dispatch/smtp.go

@@ -55,15 +55,13 @@ type SMTPHandler struct {
 
 	noAuthWarnOnce sync.Once
 	loginWarnOnce  sync.Once
-
-	helpers template.FuncMap
 }
 
-func NewSMTPHandler(cfg codersdk.NotificationsEmailConfig, helpers template.FuncMap, log slog.Logger) *SMTPHandler {
-	return &SMTPHandler{cfg: cfg, helpers: helpers, log: log}
+func NewSMTPHandler(cfg codersdk.NotificationsEmailConfig, log slog.Logger) *SMTPHandler {
+	return &SMTPHandler{cfg: cfg, log: log}
 }
 
-func (s *SMTPHandler) Dispatcher(payload types.MessagePayload, titleTmpl, bodyTmpl string) (DeliveryFunc, error) {
+func (s *SMTPHandler) Dispatcher(payload types.MessagePayload, titleTmpl, bodyTmpl string, helpers template.FuncMap) (DeliveryFunc, error) {
 	// First render the subject & body into their own discrete strings.
 	subject, err := markdown.PlaintextFromMarkdown(titleTmpl)
 	if err != nil {
@@ -79,12 +77,12 @@ func (s *SMTPHandler) Dispatcher(payload types.MessagePayload, titleTmpl, bodyTm
 	// Then, reuse these strings in the HTML & plain body templates.
 	payload.Labels["_subject"] = subject
 	payload.Labels["_body"] = htmlBody
-	htmlBody, err = render.GoTemplate(htmlTemplate, payload, s.helpers)
+	htmlBody, err = render.GoTemplate(htmlTemplate, payload, helpers)
 	if err != nil {
 		return nil, xerrors.Errorf("render full html template: %w", err)
 	}
 	payload.Labels["_body"] = plainBody
-	plainBody, err = render.GoTemplate(plainTemplate, payload, s.helpers)
+	plainBody, err = render.GoTemplate(plainTemplate, payload, helpers)
 	if err != nil {
 		return nil, xerrors.Errorf("render full plaintext template: %w", err)
 	}

coderd/notifications/dispatch/smtp/html.gotmpl

@@ -8,7 +8,7 @@
   <body style="margin: 0; padding: 0; font-family: -apple-system, system-ui, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif; color: #020617; background: #f8fafc;">
     <div style="max-width: 600px; margin: 20px auto; padding: 60px; border: 1px solid #e2e8f0; border-radius: 8px; background-color: #fff; text-align: left; font-size: 14px; line-height: 1.5;">
       <div style="text-align: center;">
-        <img src="https://coder.com/coder-logo-horizontal.png" alt="Coder Logo" style="height: 40px;" />
+        <img src="{{ logo_url }}" alt="{{ app_name }} Logo" style="height: 40px;" />
       </div>
       <h1 style="text-align: center; font-size: 24px; font-weight: 400; margin: 8px 0 32px; line-height: 1.5;">
         {{ .Labels._subject }}

coderd/notifications/dispatch/smtp_test.go

@@ -442,11 +442,7 @@ func TestSMTP(t *testing.T) {
 			require.NoError(t, hp.Set(listen.Addr().String()))
 			tc.cfg.Smarthost = hp
 
-			helpers := map[string]any{
-				"base_url":     func() string { return "http://test.com" },
-				"current_year": func() string { return "2024" },
-			}
-			handler := dispatch.NewSMTPHandler(tc.cfg, helpers, logger.Named("smtp"))
+			handler := dispatch.NewSMTPHandler(tc.cfg, logger.Named("smtp"))
 
 			// Start mock SMTP server in the background.
 			var wg sync.WaitGroup
@@ -484,7 +480,7 @@ func TestSMTP(t *testing.T) {
 				Labels:    make(map[string]string),
 			}
 
-			dispatchFn, err := handler.Dispatcher(payload, subject, body)
+			dispatchFn, err := handler.Dispatcher(payload, subject, body, helpers())
 			require.NoError(t, err)
 
 			msgID := uuid.New()

coderd/notifications/dispatch/utils_test.go

@@ -0,0 +1,10 @@
+package dispatch_test
+
+func helpers() map[string]any {
+	return map[string]any{
+		"base_url":     func() string { return "http://test.com" },
+		"current_year": func() string { return "2024" },
+		"logo_url":     func() string { return "https://coder.com/coder-logo-horizontal.png" },
+		"app_name":     func() string { return "Coder" },
+	}
+}

coderd/notifications/dispatch/webhook.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"io"
 	"net/http"
+	"text/template"
 
 	"github.com/google/uuid"
 	"golang.org/x/xerrors"
@@ -41,7 +42,7 @@ func NewWebhookHandler(cfg codersdk.NotificationsWebhookConfig, log slog.Logger)
 	return &WebhookHandler{cfg: cfg, log: log, cl: &http.Client{}}
 }
 
-func (w *WebhookHandler) Dispatcher(payload types.MessagePayload, titleMarkdown, bodyMarkdown string) (DeliveryFunc, error) {
+func (w *WebhookHandler) Dispatcher(payload types.MessagePayload, titleMarkdown, bodyMarkdown string, _ template.FuncMap) (DeliveryFunc, error) {
 	if w.cfg.Endpoint.String() == "" {
 		return nil, xerrors.New("webhook endpoint not defined")
 	}

coderd/notifications/dispatch/webhook_test.go

@@ -141,7 +141,7 @@ func TestWebhook(t *testing.T) {
 				Endpoint: *serpent.URLOf(endpoint),
 			}
 			handler := dispatch.NewWebhookHandler(cfg, logger.With(slog.F("test", tc.name)))
-			deliveryFn, err := handler.Dispatcher(msgPayload, titleMarkdown, bodyMarkdown)
+			deliveryFn, err := handler.Dispatcher(msgPayload, titleMarkdown, bodyMarkdown, helpers())
 			require.NoError(t, err)
 
 			retryable, err := deliveryFn(ctx, msgID)