Adding godotenv library to use our .env file for the smtp configuration. Updating main.go adding our logger first, load our .env file, retrieve values to initialize the mail application's struct. Updating registerUserHandler sending the user_welcome.tmpl email.

cmd/api/users.go

@@ -59,6 +59,13 @@ 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
+	}
+
 	// 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)
 	if err != nil {