Allow users to set port in env (maybe-finance#726)

* Add custom port option to env.example

* Update readme.

* Port in bin/dev looks for env var before defaulting to 3000

* Change port for mailer in dev environment.

* Revisions in dev and readme files.

.env.example

@@ -1,3 +1,7 @@
+# Custom port config
+# For users who have other applications listening at 3000, this allows them to set a value puma will listen to.
+PORT=
+
 # Exchange Rate API
 # This is used to convert between different currencies in the app. We use Synth, which is a Maybe product. You can sign up for a free account at synthfinance.com.
 SYNTH_API_KEY=
@@ -54,7 +58,7 @@ SECRET_KEY_BASE=secret-value
 # UPGRADES_MODE: Controls how the app will upgrade. `manual` means the user must manually upgrade the app. `auto` means the app will upgrade automatically (great for self-hosting)
 # UPGRADES_TARGET: Controls what the app will upgrade to. `release` means the app will upgrade to the latest release. `commit` means the app will upgrade to the latest commit.
 #
-UPGRADES_ENABLED=false # unless editing the flow, you should keep this `false` locally in development 
+UPGRADES_ENABLED=false # unless editing the flow, you should keep this `false` locally in development
 UPGRADES_MODE=manual # `manual` or `auto`
 UPGRADES_TARGET=release # `release` or `commit`
 
@@ -63,15 +67,15 @@ UPGRADES_TARGET=release # `release` or `commit`
 # Git Repository Module - responsible for fetching latest commit data for upgrades
 # ======================================================================================================
 #
-GITHUB_REPO_OWNER=maybe-finance 
+GITHUB_REPO_OWNER=maybe-finance
 GITHUB_REPO_NAME=maybe
 GITHUB_REPO_BRANCH=main
 
 # ======================================================================================================
 # Active Storage Configuration - responsible for storing file uploads
 # ======================================================================================================
 #
-# * Defaults to disk storage but you can also use Amazon S3, Google Cloud Storage, or Microsoft Azure Storage. 
+# * Defaults to disk storage but you can also use Amazon S3, Google Cloud Storage, or Microsoft Azure Storage.
 # * Set the appropriate environment variables to use these services.
 # * Ensure libvips is installed on your system for image processing - https://github.com/libvips/libvips
 #
@@ -81,4 +85,4 @@ GITHUB_REPO_BRANCH=main
 # S3_ACCESS_KEY_ID=
 # S3_SECRET_ACCESS_KEY=
 # S3_REGION= # defaults to `us-east-1` if not set
-# S3_BUCKET=
+# S3_BUCKET=

config/environments/development.rb

@@ -56,7 +56,7 @@
 
   config.action_mailer.perform_deliveries = true
 
-  config.action_mailer.default_url_options = { host: "localhost", port: 3000 }
+  config.action_mailer.default_url_options = { host: "localhost", port: ENV.fetch("PORT") { 3000 } }
 
   # Print deprecation notices to the Rails logger.
   config.active_support.deprecation = :log