misc: add helper script to create local non-containerized Redis Cluster

.gitignore

@@ -16,6 +16,7 @@ docs/site
 internal/ultra
 misc/clickhouse_cluster/clickhouse*
 misc/clickhouse_cluster/zookeeper
+misc/redis_cluster/cluster_data
 vendor/
 *.orig
 tmp/

misc/README.md

@@ -1 +1 @@
-This folder contains various tools, deploy scripts etc for Centrifugo.
+This folder contains various tools, deploy scripts etc for Centrifugo.

misc/redis_cluster/create_cluster.sh

@@ -0,0 +1,102 @@
+#!/bin/bash
+
+# Function to wait for Redis node to become available
+wait_for_redis() {
+  local port=$1
+  while ! redis-cli -p "$port" ping > /dev/null 2>&1; do
+    echo "Waiting for Redis node on port $port to start..."
+    sleep 1
+  done
+  echo "Redis node on port $port is available."
+}
+
+# Array to hold PIDs of Redis server processes
+declare -a redis_pids
+
+# Function to start Redis cluster nodes
+start_redis_cluster() {
+  local masters=$1
+  local replicas=$2
+  local base_port=7000
+  local cluster_dir="./cluster_data"
+  local total_nodes=$((masters * (replicas + 1)))
+  local redis_nodes=()
+
+  # Create cluster directory, clean previous.
+  rm -r "$cluster_dir"
+  mkdir -p "$cluster_dir"
+
+  # Start master nodes
+  for ((i=0; i<masters; i++)); do
+    local port=$((base_port + i))
+    local node_dir="$cluster_dir/$port"
+    mkdir -p "$node_dir"
+    pushd "$node_dir" > /dev/null
+
+    # Start a Redis server with cluster enabled and no replicas
+    redis-server --port "$port" --cluster-enabled yes \
+                 --cluster-config-file "nodes.conf" \
+                 --cluster-node-timeout 5000 --appendonly yes \
+                 --appendfilename "appendonly.aof" \
+                 --dbfilename "dump.rdb" \
+                 --logfile "redis.log" &
+    redis_pids[i]=$!
+    popd > /dev/null
+    redis_nodes+=("127.0.0.1:$port")
+  done
+
+  # Start replica nodes
+  for ((i=0; i<masters * replicas; i++)); do
+    local port=$((base_port + masters + i))
+    local node_dir="$cluster_dir/$port"
+    mkdir -p "$node_dir"
+    pushd "$node_dir" > /dev/null
+
+    # Start a Redis server with cluster enabled and no replicas
+    redis-server --port "$port" --cluster-enabled yes \
+                 --cluster-config-file "nodes.conf" \
+                 --cluster-node-timeout 5000 --save "" --appendonly no \
+                 --appendfilename "appendonly.aof" \
+                 --dbfilename "dump.rdb" \
+                 --logfile "redis.log" &
+    local pid=$!
+    redis_pids+=("$pid")
+    popd > /dev/null
+    redis_nodes+=("127.0.0.1:$port")
+  done
+
+  # Wait for all nodes to become available
+  for port in "${redis_nodes[@]}"; do
+    wait_for_redis "${port##*:}"
+  done
+
+  # Create the cluster with replicas
+  echo "Creating Redis cluster with the following nodes: ${redis_nodes[*]}"
+  yes "yes" | redis-cli --cluster create "${redis_nodes[@]}" --cluster-replicas "$replicas"
+}
+
+# Function to shut down Redis cluster nodes
+shutdown_redis_cluster() {
+  echo "Shutting down Redis cluster nodes..."
+  for pid in "${redis_pids[@]}"; do
+    kill "$pid"
+  done
+}
+
+# Trap Ctrl+C (SIGINT) to call shutdown function
+trap shutdown_redis_cluster SIGINT
+
+# Check if the number of masters and replicas is provided
+if [ -z "$1" ] || [ -z "$2" ]; then
+  echo "Usage: $0 <number_of_masters> <number_of_replicas_per_master>"
+  exit 1
+fi
+
+# Start the Redis cluster
+start_redis_cluster "$1" "$2"
+
+# Wait until a keyboard interrupt (Ctrl+C) is detected
+echo "Redis cluster is running. Press Ctrl+C to stop."
+wait
+
+# The script will wait at the above line until the user presses Ctrl+C, which will trigger the shutdown function

misc/redis_cluster/readme.md

@@ -0,0 +1,9 @@
+Create local Redis cluster consisting of N nodes with M replicas each, ex:
+
+```
+bash create_cluster.sh 3 0
+```
+
+Cluster nodes will work until script interrupted. The goal of having this script is for development and benchmarking.
+
+All data will be saved to local directory `cluster_data`. By default, Redis runs without RDB and AOF (`--save "" --appendonly no`).