Merge pull request redislabs-training#26 from redislabs-training/add-…

…docker-compose-instructions

Added Docker instructions / Discord call to action.

README.md

@@ -3,6 +3,8 @@
 Introduction
 ---
 
+![Screenshot](screenshot.png)
+
 This is the sample application codebase for RU102J, [Redis for Java Developers](https://university.redis.com/courses/ru102j/) at [Redis University](https://university.redis.com).
 
 Solutions to the course programming challenges can be found on the `solutions` branch.
@@ -13,22 +15,62 @@ Prerequisites
 In order to start and run this application, you will need:
 
 * Java 8 JDK or higher
-* Maven
-* Access to a local or remote installation of [Redis](https://redis.io/download) version 5 or newer (local preferred)
-* If you want to try the RedisTimeSeries exercises, you'll need to make sure that your Redis installation also has the [RedisTimeSeries Module](https://oss.redis.com/redistimeseries/) installed
+* [Maven](https://maven.apache.org/)
+* Access to a local or remote installation of [Redis](https://redis.io/download) version 5 or newer (local preferred, Docker is a good option - see instructions below)
+* If you want to try the RedisTimeSeries exercises, you'll need to make sure that your Redis installation also has the [RedisTimeSeries Module](https://oss.redis.com/redistimeseries/) installed (or use the provided Docker Compose file which gives you Redis with RedisTimeSeries)
+* Optional: [Docker](https://www.docker.com/get-started/)
+* Optional but recommended: [RedisInsight](https://redis.com/redis-enterprise/redis-insight/) to visualize the data in Redis.  This is a graphical alternative to the `redis-cli` command
 
 If you're using Windows, check out the following resources for help with running Redis:
 
-* [Redis Labs Blog - Running Redis on Windows 10](https://redis.com/blog/redis-on-windows-10/)
+* [Redis Blog - Running Redis on Windows 10](https://redis.com/blog/redis-on-windows-10/)
 * [Microsoft - Windows Subsystem for Linux Installation Guide for Windows 10](https://docs.microsoft.com/en-us/windows/wsl/install-win10)
 
+Running Redis with Docker
+---
+
+We've provided a Docker Compose file as part of this repo, so to start Redis with the RedisTimeSeries module installed, use the following command:
+
+```bash
+docker-compose up -d
+```
+
+This will start a Redis with RedisTimeSeries container on localhost port 6379 with no password and you should see output similar to the following:
+
+```
+Creating network "ru102j_default" with the default driver
+Creating redis_ru102j ... done
+```
+
+Connect to Redis using either RedisInsight, or the `redis-cli` command.  When using `redis-cli` you can invoke it from the Docker container like this:
+
+```bash
+docker exec -it redis_ru102j redis-cli
+```
+
+When you see this prompt:
+
+```
+127.0.0.1:6379>
+```
+
+you are connected to Redis.  Type `quit` to exit the Redis CLI.
+
+When you are finished working with Redis, shut down the server like so:
+
+```bash
+docker-compose down
+```
+
+Redis saves your data in an append only file in the `redisdata` folder, and will re-load it next time you start the container.
+
 How to Start the RediSolar Application
 ---
 
 ### When using Redis on localhost, port 6379 with no password:
 
 1. Run `mvn package` to build your application.
-2. Load the sample data: `java -jar target/redisolar-1.0.jar load`.  If you want to erase everything in Redis before loading the data, use `java -jar target/redisolar-1.0.jar load --flush true`, but be aware that this will delete ALL keys in your Redis database.
+2. Load the sample data: `java -jar target/redisolar-1.0.jar load`.  If you want to erase everything in Redis before loading the data, use `java -jar target/redisolar-1.0.jar load --flush true`, but be aware that this will delete ALL keys in your Redis database.  Note that loading the data may take a few minutes.
 3. Start the application with `java -jar target/redisolar-1.0.jar server config.yml`
 4. To check that your application is running enter url `http://localhost:8081`, substituting `localhost` for the hostname that you're running the application on if necessary.
 
@@ -71,9 +113,10 @@ To rebuild the application without running the tests:
 mvn package -DskipTests 
 ```
 
-Application Screenshot
+Need Help / Join our Community
 ---
-![Screenshot](screenshot.png)
+
+If you need help with the course or want to chat to your fellow students and the wider Redis community, please [join us on our Discord server](https://discord.gg/jucCB8h).
 
 Subscribe to our YouTube Channel / Follow us on Twitch
 ---