To quickly test changes to email template copy and styling, I created a couple routes that are only accessible in the dev environment: if Mix.env() == :dev do get("/email_previews", EmailPreviewController, :index) get("/email_previews/:email", EmailPreviewController, :show) end However, this n…

Try wrapping the for loop in a if Mix.env() == :dev block.

You don’t want to do Mix.env calls at runtime. Does the email_preview_path exist in a view that only is needed in dev?

Oh, right! I guess it’s different for routes because they’re compiled?

Right, the if Mix.env == :dev do call in the router happens at compile time because it’s in the module body.

Yes, it only exists in a template that’s needed in dev.

You could use Mix.env == :dev at compile time: <ul> <%= if unquote(Mix.env() == :dev), do: for email <- @emails do %> <li><a href="<%= email_preview_path(@conn, :show, to_string(email)) %>"><%= email %></a></li> <% end %> </ul>

When one needs different modules to be compiled in different environments, it’d be better to explicitly define these module sets, instead of polluting the source code with conditionals. For the modules to be available in :test only, the common approach is to create test/support folder, and modify…

I literally laughed out loud and then facepalmed after reading your suggestion. Thanks!

I ended up going with the solution suggested by @andrejsm but I did give this a try out of curiosity and couldn’t get it to work. At first, I was getting a syntax error, so I switched to a multi-line if statement to see if that was the cause—that fixed the syntax error but resulted in the same compi…

Yeah the if unquote(Mix.env() == :dev) probably isn’t going to work. Templates are ultimately compiled into the view modules, so if you did: if Mix.env == :dev do defmodule MyAppWeb.SomeView do # etc end end Where MyAppWeb.SomeView is whatever view module is related to that template I belie…

Dev-only routes

Questions & Help Questions

andrejsm November 20, 2019, 5:13am 7

Simply don’t use the compiled path functions. Instead type them as strings and interpolate values.