Add deployment

Author: vtm9

k8s/app-chart/templates/codebattle_deployment.yaml

@@ -17,6 +17,7 @@ spec:
       labels:
         app: "codebattle"
     spec:
+      terminationGracePeriodSeconds: {{ .Values.codebattle.rollout.terminationGracePeriodSeconds }}
       {{- with .Values.codebattle.affinity }}
       affinity:
         {{- toYaml . | nindent 8 }}
@@ -48,12 +49,27 @@ spec:
           command:
             - make
             - start
+          lifecycle:
+            preStop:
+              exec:
+                command:
+                  - /bin/sh
+                  - -c
+                  - "curl -s -X POST http://127.0.0.1:4000/health/drain || true; curl -s -X POST http://127.0.0.1:4000/health/handoff || true; until [ \"$(curl -s -o /dev/null -w '%{http_code}' http://127.0.0.1:4000/health/release_ready)\" = \"200\" ]; do sleep 2; done; sleep {{ .Values.codebattle.rollout.preStopSleepSeconds }}"
           envFrom:
             - secretRef:
                 name: codebattle-secrets
             - configMapRef:
                 name: codebattle-env
                 optional: true
           env:
+            - name: POD_IP
+              valueFrom:
+                fieldRef:
+                  fieldPath: status.podIP
+            - name: POD_NAME
+              valueFrom:
+                fieldRef:
+                  fieldPath: metadata.name
             - name: DEPLOYED_AT
               value: {{ dateInZone "2006-01-02 15:04:05" (now) "UTC" }}

k8s/app-chart/values.yaml

@@ -18,6 +18,9 @@ codebattle:
   image:
     repository: hexlet-codebattle/codebattle
     imagePullPolicy: Always
+  rollout:
+    preStopSleepSeconds: 5
+    terminationGracePeriodSeconds: 7200
   service:
     type: ClusterIP
     port: 4000

services/app/apps/codebattle/assets/js/socket.js

@@ -56,6 +56,9 @@ export const channelTopics = {
   tournamentPlayerFinishedTopic: 'tournament:player:finished',
   tournamentActivated: 'tournament:activated',
   tournamentCanceled: 'tournament:canceled',
+  deployHandoffStarted: 'deploy:handoff_started',
+  deployHandoffDone: 'deploy:handoff_done',
+  deployHandoffFailed: 'deploy:handoff_failed',
 
   roundCreatedTopic: 'round:created',
 

services/app/apps/codebattle/assets/js/widgets/middlewares/Main.js

@@ -71,6 +71,38 @@ const redirectToNewGame = (data) => (_dispatch, getState) => {
   }
 };
 
+const deployBannerId = 'cb-deploy-handoff-banner';
+
+const renderDeployBanner = (text, backgroundColor = '#2f3747') => {
+  const existing = document.getElementById(deployBannerId);
+  const el = existing || document.createElement('div');
+
+  el.id = deployBannerId;
+  el.textContent = text;
+  el.style.position = 'fixed';
+  el.style.top = '0';
+  el.style.left = '0';
+  el.style.right = '0';
+  el.style.zIndex = '2000';
+  el.style.padding = '8px 12px';
+  el.style.textAlign = 'center';
+  el.style.fontSize = '14px';
+  el.style.color = '#ffffff';
+  el.style.backgroundColor = backgroundColor;
+
+  if (!existing) {
+    document.body.appendChild(el);
+  }
+};
+
+const removeDeployBanner = () => {
+  const existing = document.getElementById(deployBannerId);
+
+  if (existing) {
+    existing.remove();
+  }
+};
+
 const initPresence = (followId) => (dispatch) => {
   channel = new Channel('main', {
     ...getUserStateByPath(),
@@ -109,6 +141,25 @@ const initPresence = (followId) => (dispatch) => {
       (data) => {
         camelizeKeysAndDispatch(dispatch, actions.changeTournamentState)(data);
       },
+    ).addListener(
+      channelTopics.deployHandoffStarted,
+      () => {
+        renderDeployBanner('Deploy in progress. Reconnecting game session...');
+      },
+    ).addListener(
+      channelTopics.deployHandoffDone,
+      () => {
+        renderDeployBanner('Deploy finished. Syncing latest session...', '#3a8b3a');
+        setTimeout(() => {
+          removeDeployBanner();
+          window.location.reload();
+        }, 1200);
+      },
+    ).addListener(
+      channelTopics.deployHandoffFailed,
+      () => {
+        renderDeployBanner('Deploy handoff incomplete. Reconnecting...', '#b34d4d');
+      },
     );
 };
 

services/app/apps/codebattle/lib/codebattle/cluster.ex

@@ -0,0 +1,58 @@
+defmodule Codebattle.Cluster do
+  @moduledoc false
+
+  @default_wait_timeout_ms 15_000
+  @retry_delay_ms 500
+
+  def connected_nodes do
+    Node.list(:connected)
+  end
+
+  def choose_target_node do
+    env_target = System.get_env("CODEBATTLE_HANDOFF_TARGET_NODE")
+
+    case parse_node(env_target) do
+      nil ->
+        connected_nodes()
+        |> Enum.sort()
+        |> List.first()
+
+      target_node ->
+        if target_node in connected_nodes(), do: target_node
+    end
+  end
+
+  def wait_for_target_node(timeout_ms \\ @default_wait_timeout_ms) do
+    if is_nil(parse_node(System.get_env("CODEBATTLE_HANDOFF_TARGET_NODE"))) and connected_nodes() == [] do
+      nil
+    else
+      deadline = System.monotonic_time(:millisecond) + timeout_ms
+      wait_for_target_node_until(deadline)
+    end
+  end
+
+  defp wait_for_target_node_until(deadline) do
+    case choose_target_node() do
+      nil ->
+        if System.monotonic_time(:millisecond) < deadline do
+          Process.sleep(@retry_delay_ms)
+          wait_for_target_node_until(deadline)
+        end
+
+      node ->
+        node
+    end
+  end
+
+  defp parse_node(nil), do: nil
+  defp parse_node(""), do: nil
+
+  defp parse_node(raw) when is_binary(raw) do
+    raw
+    |> String.trim()
+    |> case do
+      "" -> nil
+      value -> String.to_atom(value)
+    end
+  end
+end