Phoenix Upgrade
There are the steps I followed to upgrade a Phoenix app from 1.5.6 to 1.5.8.
mix archive.uninstall phx_new
mix archive.install hex phx_new 1.5.8
Then, following https://www.phoenixdiff.org/?source=1.5.6&target=1.5.8, update the versions defined in mix.exs
and the various files.
mix deps.get
If there are changes to the javascript dependencies then
cd assets
npm install
Start everything with
mix phx.server