From 32263f00bc069e90f52ed87f73a9adde4aeac157 Mon Sep 17 00:00:00 2001
From: Alessandro Rodi <alessandro.rodi@renuo.ch>
Date: Wed, 17 Dec 2025 16:21:41 +0100
Subject: [PATCH] Introduce a vector sidecar process

---
 config/puma_plugins/vector.rb | 94 +++++++++++++++++++++++++++++++++++
 config/udp_logger.rb          | 40 +++++++++++++++
 config/vector.toml            | 32 ++++++++++++
 3 files changed, 166 insertions(+)
 create mode 100644 config/puma_plugins/vector.rb
 create mode 100644 config/udp_logger.rb
 create mode 100644 config/vector.toml

diff --git a/config/puma_plugins/vector.rb b/config/puma_plugins/vector.rb
new file mode 100644
index 0000000..c089e1d
--- /dev/null
+++ b/config/puma_plugins/vector.rb
@@ -0,0 +1,94 @@
+# frozen_string_literal: true
+
+require "puma/plugin"
+require "rbconfig"
+require "timeout"
+require "shellwords"
+
+Puma::Plugin.create do
+  def start(launcher)
+    @launcher = launcher
+    @events = launcher.events
+    @options = launcher.config.options
+    @vector_pid = nil
+
+    setup_paths
+    start_vector
+    register_hooks
+  end
+
+  private
+
+  def setup_paths
+    @app_root = @options[:directory] || Dir.pwd
+    @vector_bin = env_or_option("ONLYLOGS_VECTOR_BIN", :onlylogs_vector_bin, "vector")
+    @vector_config = env_or_option(
+      "ONLYLOGS_VECTOR_CONFIG",
+      :onlylogs_vector_config,
+      File.expand_path("../vector.toml", __dir__)
+    )
+    @vector_args = env_or_option("ONLYLOGS_VECTOR_ARGS", :onlylogs_vector_args, "")
+    @dsn = env_or_option("ONLYLOGS_DSN", :onlylogs_dsn, "https://onlylogs.io/drain/testmac")
+  end
+
+  def register_hooks
+    events = @launcher.events
+    events.register(:on_restart) { restart_vector }
+    at_exit { stop_vector }
+  end
+
+  def env_or_option(env_key, option_key, default)
+    ENV.fetch(env_key, @options.fetch(option_key, default))
+  end
+
+  def start_vector
+    stop_vector if @vector_pid
+
+    unless File.exist?(@vector_config)
+      warn "Vector config not found at #{@vector_config}; skipping start"
+      return
+    end
+
+    args = [ @vector_bin, "--config", @vector_config ]
+    args += Shellwords.split(@vector_args.to_s) unless @vector_args.to_s.empty?
+
+    info "Starting Vector sidecar (config: #{@vector_config}, dsn: #{@dsn})"
+    env = { "ONLYLOGS_DSN" => @dsn }
+    @vector_pid = Process.spawn(env, *args, chdir: @app_root, pgroup: true)
+  rescue Errno::ENOENT => e
+    error "Unable to start Vector sidecar: #{e.message}"
+  end
+
+  def restart_vector
+    info "Restarting Vector sidecar"
+    start_vector
+  end
+
+  def stop_vector
+    return unless @vector_pid
+
+    info "Stopping Vector sidecar"
+    pgid = Process.getpgid(@vector_pid)
+    Process.kill("TERM", -pgid)
+    Timeout.timeout(5) { Process.wait(@vector_pid) }
+  rescue Errno::ESRCH, Errno::ECHILD
+    # already stopped
+  rescue Timeout::Error
+    warn "Vector sidecar did not stop in time, killing"
+    Process.kill("KILL", -pgid) rescue nil
+  ensure
+    @vector_pid = nil
+  end
+
+  def info(message)
+    @events.log("[VectorSidecar] #{message}")
+  end
+
+  def warn(message)
+    @events.log("[VectorSidecar][WARN] #{message}")
+  end
+
+  def error(message)
+    @events.error("[VectorSidecar][ERROR] #{message}")
+  end
+end
diff --git a/config/udp_logger.rb b/config/udp_logger.rb
new file mode 100644
index 0000000..f6248f7
--- /dev/null
+++ b/config/udp_logger.rb
@@ -0,0 +1,40 @@
+# udp_logger.rb
+require "logger"
+require "socket"
+
+class UdpLogger < Logger
+  def initialize(host: "127.0.0.1", port: 6000, local_fallback: $stdout)
+    # Use a normal Logger underneath so we still see logs locally
+    super(local_fallback)
+
+    @udp_host = host
+    @udp_port = port
+    @socket   = UDPSocket.new
+  end
+
+  # Override Logger#add, which all the level methods delegate to
+  def add(severity, message = nil, progname = nil, &block)
+    # Same semantics as Logger:
+    if message.nil?
+      if block_given?
+        message = block.call
+      else
+        message = progname
+        progname = nil
+      end
+    end
+
+    # Send plain text over UDP to Vector
+    begin
+      payload = message.to_s
+      @socket.send(payload, 0, @udp_host, @udp_port)
+    rescue => e
+      # Swallow UDP errors so logging never crashes the app
+      warn "UDP logger error: #{e.class}: #{e.message}"
+    end
+
+    # Also log locally (stdout / file) via normal Logger behavior
+    super(severity, message, progname, &block)
+  end
+end
+
diff --git a/config/vector.toml b/config/vector.toml
new file mode 100644
index 0000000..e659e1a
--- /dev/null
+++ b/config/vector.toml
@@ -0,0 +1,32 @@
+# Where Vector keeps internal state (buffers, etc.)
+data_dir = "/usr/local/var/lib/vector"
+
+# --- 1) SOURCE: UDP socket listening on localhost:6000 ---
+
+[sources.udp_logs]
+type = "socket"
+mode = "udp"                       # UDP mode
+address = "127.0.0.1:6000"
+
+# --- 2) SINK: console (for debugging, optional but very handy) ---
+
+[sinks.console]
+type = "console"
+inputs = ["udp_logs"]
+encoding.codec = "json"
+target = "stdout"
+
+# --- 3) SINK: Onlylogs HTTP drain ---
+
+[sinks.onlylogs]
+type = "http"
+inputs = ["udp_logs"]             # consume events from udp_logs
+method = "post"
+uri = "${ONLYLOGS_DSN}"
+
+encoding.codec = "text"
+
+#[sinks.onlylogs.request]
+# Adjust headers if Onlylogs expects something specific
+#headers.Content-Type = "application/json"
+