refactor: link controller buffered channel to hold click data

app/controllers/click.cr

@@ -4,6 +4,82 @@ module App::Controllers
     include App::Lib
     include App::Services
 
+    # Buffered channel to hold click data
+    @@click_channel = Channel(NamedTuple(
+      link_id: Int64,
+      remote_address: String,
+      user_agent: String?,
+      referer: String
+    )).new(10000) # Buffer size
+
+    @@processor_started = begin
+      spawn do
+        batch_size = 125
+        batch = [] of NamedTuple(
+          link_id: Int64,
+          remote_address: String,
+          user_agent: String?,
+          referer: String
+        )
+
+        loop do
+          select
+          when click_data = @@click_channel.receive
+            batch << click_data
+
+            # Collect clicks until we have a batch or a timeout
+            if batch.size >= batch_size
+              process_click_batch(batch)
+              batch.clear
+            end
+          when timeout(0.5.seconds)
+            # Process whatever we have after timeout
+            unless batch.empty?
+              process_click_batch(batch)
+              batch.clear
+            end
+          end
+        end
+      end
+      true
+    end
+
+    private def self.process_click_batch(batch)
+      clicks = [] of App::Models::Click
+
+      batch.each do |click_data|
+        begin
+          client_ip = IpLookup.ip_from_address(click_data[:remote_address])
+          family, _, _, os = UserAgent.parse(click_data[:user_agent] || "")
+
+          click = App::Models::Click.new
+          click.link_id = click_data[:link_id]
+          click.country = client_ip ? IpLookup.country(client_ip) : nil
+          click.user_agent = click_data[:user_agent]
+          click.browser = family
+          click.os = os.try &.[0]  # OS family
+          click.referer = click_data[:referer]
+
+          clicks << click
+        rescue ex
+          Log.error { "Click data processing error: #{ex.message}" }
+        end
+      end
+
+      # Batch insert clicks if any were successfully processed
+       unless clicks.empty?
+        begin
+          multi = Crecto::Multi.new
+          clicks.each do |click|
+            multi.insert(click)
+          end
+          Database.transaction(multi)
+        rescue ex
+          Log.error { "Batch click insertion error: #{ex.message}" }
+        end
+      end
+    end
+
     def self.redirect_handler
       ->(env : HTTP::Server::Context) {
         link_id, url = Database.raw_query("SELECT id, url FROM links WHERE slug = (?) LIMIT 1", env.params.url["slug"]) do |result|
@@ -16,26 +92,17 @@ module App::Controllers
         env.response.headers.add("Location", url)
         env.response.headers.add("X-Forwarded-For", remote_address)
 
-        spawn do
-          begin
-            client_ip = IpLookup.ip_from_address(remote_address)
-            user_agent_str = env.request.headers["User-Agent"]?
-            referer = env.request.headers["Referer"]?.try { |r| URI.parse(r).host rescue r } || env.params.query["utm_source"]? || "Direct"
-
-            family, _, _, os = user_agent_str ? UserAgent.parse(user_agent_str) : {nil, nil, nil, nil}
-
-            click = App::Models::Click.new
-            click.link_id = link_id
-            click.country = client_ip ? IpLookup.country(client_ip) : nil
-            click.user_agent = user_agent_str
-            click.browser = family
-            click.os = os.try &.[0]  # Access the first element of the os tuple (the family)
-            click.referer = referer
-
-            Database.insert(click)
-          rescue ex
-            Log.error { "Click tracking error: #{ex.message}" }
-          end
+        begin
+          @@click_channel.send({
+            link_id: link_id,
+            remote_address: remote_address,
+            user_agent: env.request.headers["User-Agent"]?,
+            referer: env.request.headers["Referer"]?.try { |r| URI.parse(r).host rescue r } || env.params.query["utm_source"]? || "Direct"
+          })
+        rescue Channel::ClosedError
+          Log.error { "Click channel closed" }
+        rescue ex
+          Log.error { "Error queuing click: #{ex.message}" }
         end
       }
     end