Add formatter for Caddyfile (radian-software#136)

apheleia.el

@@ -943,6 +943,7 @@ being run, for diagnostic purposes."
   '((bean-format . ("bean-format"))
     (black . ("black" "-"))
     (brittany . ("brittany"))
+    (caddyfmt . ("caddy" "fmt" "-"))
     (clang-format . ("clang-format"
                      "-assume-filename"
                      (or (buffer-file-name)
@@ -1130,6 +1131,7 @@ function: %s" command)))
     (bash-ts-mode . shfmt)
     (beancount-mode . bean-format)
     (c++-ts-mode . clang-format)
+    (caddyfile-mode . caddyfmt)
     (cc-mode . clang-format)
     (c-mode . clang-format)
     (c-ts-mode . clang-format)

test/formatters/installers/caddyfmt.bash

@@ -0,0 +1,18 @@
+ver="$(latest_release caddyserver/caddy)"
+
+arch="$(uname -m)"
+case "${arch}" in
+    "x86_64")
+        arch="amd64"
+        ;;
+    "aarch64")
+        arch="arm64"
+        ;;
+    *)
+        echo >&2 "unsupported architecture: ${arch}"
+        exit 1
+        ;;
+esac
+
+curl -L -s "https://github.com/caddyserver/caddy/releases/download/${ver}/caddy_$(echo $ver | sed 's|^v||g')_linux_${arch}.tar.gz" | \
+    tar zxv -C /usr/local/bin/ caddy

test/formatters/samplecode/caddyfmt/in.caddyfile1

@@ -0,0 +1,4 @@
+example.com {
+	   root * /var/www
+	file_server
+}

test/formatters/samplecode/caddyfmt/out.caddyfile1

@@ -0,0 +1,4 @@
+example.com {
+	root * /var/www
+	file_server
+}