Sending background emails.

cmd/api/users.go

@@ -59,15 +59,19 @@ func (app *application) registerUserHandler(w http.ResponseWriter, r *http.Reque
 		return
 	}
 
-	// Call the Send() method on our Mail, passing in the user's email address, name of the template file, and the User struct containing the new user's data.
-	err = app.mailer.Send(user.Email, "user_welcome.tmpl", user)
-	if err != nil {
-		app.serverErrorResponse(w, r, err)
-		return
-	}
+	// Use the background helper to execute an anonymous function that send the welcome email
+	app.background(func() {
+		// Call the Send() method on our Mail, passing in the user's email address, name of the template file, and the User struct containing the new user's data.
+		err = app.mailer.Send(user.Email, "user_welcome.tmpl", user)
+		
+		if err != nil {
+			// Importantly, if there is an error sending the email, then we use the app.logger.Error() helper to manage it, instead of the app.serverErrorResponse() helper like before.
+			app.logger.Error(err.Error())
+		}
+	})
 
-	// Write a JSON response containing the user data along with a 201 Created status code
-	err = app.writeJSON(w, http.StatusCreated, envelope{"user": user}, nil)
+	// Not that we also change this to send the client a 202 Accepted status code. This status code indicates that the request has been accepted for processing, but the processing has not been completed.
+	err = app.writeJSON(w, http.StatusAccepted, envelope{"user": user}, nil)
 	if err != nil {
 		app.serverErrorResponse(w, r, err)
 	}