Add logging to the hook

Author: rafaelfranca

.gitignore

@@ -1 +1,2 @@
 run-rails-master-hook
+/log

config.ru

@@ -2,6 +2,17 @@
 
 require "fileutils"
 require "rack"
+require "logger"
+
+# Setup logger - log to STDOUT for systemd
+logger = Logger.new(STDOUT)
+logger.level = ENV["LOG_LEVEL"] ? Logger.const_get(ENV["LOG_LEVEL"].upcase) : Logger::INFO
+logger.formatter = proc do |severity, datetime, progname, msg|
+  "#{severity}: #{msg}\n"
+end
+
+# Use Rack::CommonLogger for HTTP request logging
+use Rack::CommonLogger, logger
 
 run_file  = ENV["RUN_FILE"] || "#{__dir__}/run-rails-master-hook"
 scheduled = <<EOS
@@ -20,10 +31,15 @@ EOS
 
 map "/rails-master-hook" do
   run ->(env) do
-    if env["REQUEST_METHOD"] == "POST"
+    request_method = env["REQUEST_METHOD"]
+
+    if request_method == "POST"
+      logger.info "Triggering Rails master hook by touching #{run_file}"
       FileUtils.touch(run_file)
+      logger.info "Rails master hook scheduled successfully"
       [200, {"Content-Type" => "text/plain", "Content-Length" => scheduled.length.to_s}, [scheduled]]
     else
+      logger.warn "Rejected non-POST request (#{request_method}) to /rails-master-hook"
       [404, {"Content-Type" => "text/plain", "Content-Length" => "0"}, []]
     end
   end