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content/Docker/Wait for redis.md

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+[wait-for-it.sh](https://github.com/vishnubob/wait-for-it) doing a great job of waiting for different services to become alive, but on #MacOs #docker is binding port on container start, seconds before redis is ready to accept connections
+
+This script waits for first successful ping or exits with non-zero status after 3 minutes.
+
+```shell
+# Waits for redis to become actually available
+wait_for_redis() {
+  timeout=180 # 3 minutes
+  i=0
+  while ! docker exec -it "$1" redis-cli -h localhost -p 6379 -a "$2" ping | grep "PONG" >/dev/null 2>&1; do
+    sleep 1;
+
+    i=$(($i+1))
+    if [[ ${i} -ge ${timeout} ]]; then
+      echo "[Error] can't properly ping Redis container after ${i} secs"
+      exit 1;
+    fi
+  done
+}
+
+# usage: wait_for_redis miin-redis-dev password
+```
+
+[Wait for mysql](Wait%20for%20mysql.md)