Support custom app directory location

README.md

@@ -176,7 +176,7 @@ On systems with SELinux you may have to run `restorecon /path/to/puma-dev` in or
 
 Simply symlink your app's directory into `~/.puma-dev`! That's it!
 
-You can use the built-in helper subcommand: `puma-dev link [-n name] [dir]` to link app directories into your puma-dev directory (`~/.puma-dev` by default).
+You can use the built-in helper subcommand: `puma-dev link [-n name] [dir]` to link app directories into your puma-dev directory (`~/.puma-dev` by default, but can be changed with `PUMA_DEV_APP_DIR`).
 
 ### Options
 
@@ -352,4 +352,3 @@ To build puma-dev, follow these steps:
 Tagged builds (e.g `v0.18.0`) will automatically create [pre-release](https://github.com/puma/puma-dev/releases) with artifacts for use in the Homebrew formula.
 
 All [builds with passing tests](https://github.com/puma/puma-dev/actions) will publish binaries that are saved for 90 days.
-

cmd/puma-dev/main_darwin.go

@@ -21,7 +21,7 @@ var (
 	fDNSPort  = flag.Int("dns-port", 9253, "port to listen on dns for")
 	fHTTPPort = flag.Int("http-port", 9280, "port to listen on http for")
 	fTLSPort  = flag.Int("https-port", 9283, "port to listen on https for")
-	fDir      = flag.String("dir", "~/.puma-dev", "directory to watch for apps")
+	fDir      = flag.String("dir", dev.GetEnv("PUMA_DEV_APP_DIR", "~/.puma-dev"), "directory to watch for apps")
 	fTimeout  = flag.Duration("timeout", 15*60*time.Second, "how long to let an app idle for")
 	fPow      = flag.Bool("pow", false, "Mimic pow's settings")
 	fLaunch   = flag.Bool("launchd", false, "Use socket from launchd")

cmd/puma-dev/main_linux.go

@@ -17,7 +17,7 @@ import (
 
 var (
 	fDebug              = flag.Bool("debug", false, "enable debug output")
-	fDir                = flag.String("dir", "~/.puma-dev", "directory to watch for apps")
+	fDir                = flag.String("dir", dev.GetEnv("PUMA_DEV_APP_DIR", "~/.puma-dev"), "directory to watch for apps")
 	fDomains            = flag.String("d", "test", "domains to handle, separate with :, defaults to test")
 	fHTTPPort           = flag.Int("http-port", 9280, "port to listen on http for")
 	fNoServePublicPaths = flag.String("no-serve-public-paths", "", "Disable static file server for specific paths under /public")

dev/get_env.go

@@ -0,0 +1,8 @@
+package dev
+
+func GetEnv(key, fallback string) string {
+	if value, ok := os.LookupEnv(key); ok {
+		return value
+	}
+	return fallback
+}