[misc] add scripts for testing redis cluster

libraries/redis-wrapper/test/scripts/cluster/clear-dbs.sh

@@ -0,0 +1,4 @@
+while true; do
+  seq 0 8 \
+  | xargs -I% redis-cli -p 700% FLUSHALL > /dev/null
+done

libraries/redis-wrapper/test/scripts/cluster/cluster.js

@@ -0,0 +1,25 @@
+/*
+  execute this script with a redis cluster running to test the health check.
+  starting and stopping shards with this script running is a good test.
+
+  to create a new cluster, use $ ./create-redis-cluster.sh
+  to run a chaos monkey, use $ ./clear-dbs.sh
+*/
+
+const redis = require('../../../')
+
+const rclient = redis.createClient({
+  cluster: Array.from({ length: 9 }).map((value, index) => {
+    return { host: '127.0.0.1', port: 7000 + index }
+  }),
+})
+
+setInterval(() => {
+  rclient.healthCheck((err) => {
+    if (err) {
+      console.log('HEALTH CHECK FAILED', err)
+    } else {
+      console.log('HEALTH CHECK OK')
+    }
+  })
+}, 1000)

libraries/redis-wrapper/test/scripts/cluster/create-cluster.sh

@@ -0,0 +1,73 @@
+#!/bin/bash
+
+# USAGE: $0 [NUMBER_OF_NODES, default: 9] [DATA_DIR, default: a new temp dir]
+#
+# ports are assigned from 7000 on
+#
+# NOTE: the cluster setup requires redis 5+
+
+set -ex
+
+COUNT=${1:-9}
+DATA=$2
+
+if [[ -z "$DATA" ]]; then
+  IS_TEMP=1
+  TEMP=`mktemp -d`
+  DATA="$TEMP"
+fi
+
+HAS_DATA=
+if [[ -e "$DATA/7000/node.conf" ]]; then
+    HAS_DATA=1
+fi
+
+PIDs=""
+
+cleanup() {
+  # ensure that we delete the temp dir, no matter how the kill cmd exists
+  set +e
+  # invoke kill with at least one PID
+  echo "$PIDs" | xargs -r kill
+  if [[ ! -z "$IS_TEMP" ]]; then
+    rm -rf "$TEMP"
+  fi
+}
+trap cleanup exit
+
+for NUM in `seq "$COUNT"`; do
+  PORT=`expr 6999 + "$NUM"`
+  CWD="$DATA/$PORT"
+  mkdir -p "$CWD"
+  pushd "$CWD"
+  redis-server \
+    --appendonly no \
+    --cluster-enabled yes \
+    --cluster-config-file node.conf \
+    --port "$PORT" \
+    --save "" \
+    > /dev/null \
+  &
+  PIDs="$PIDs $!"
+  popd
+done
+
+# initial nodes
+if [[ -z "$HAS_DATA" ]]; then
+  # confirm the setup
+  echo yes \
+  | redis-cli --cluster create 127.0.0.1:7000 127.0.0.1:7001 127.0.0.1:7002
+fi
+
+# scale up as requested
+for NUM in `seq 4 "$COUNT"`; do
+  PORT=`expr 6999 + "$NUM"`
+  GUARD="$DATA/$PORT/.joined"
+  if [[ ! -e "$GUARD" ]]; then
+    redis-cli --cluster add-node "127.0.0.1:$PORT" 127.0.0.1:7000 --cluster-slave
+    touch "$GUARD"
+  fi
+done
+
+echo "CLUSTER IS READY" >&2
+wait