pepcmarques / ru101

Source code and examples for Redis University RU101 Introduction to Redis Data Structures

Redis University RU101: Introduction to Redis Data Structures

Introduction

This repo contains the sample data and Python code for RU101, Introduction to Redis Data Structures at Redis University.

Setup

Redis Stack is an easy to install bundle of Redis plus additional capabilities. You'll need to clone this repository to your machine, and setup Redis Stack and Python as described below. Read more about Redis Stack here.

Redis Stack

There are multiple ways that you can install Redis Stack, options include:

• Use a free Redis Stack instance in the cloud - see the "Setup" page in the course materials when logged in to Redis University.
• Use the Redis Stack container from Docker Hub.
• If you want to install Redis Stack directly on your machine, it's available via popular package managers for different operating systems. Follow the installation instructions here.

Python

This course requires Python 3. You should create and use a virtual environment when running the code and loading the sample data into Redis. You'll also need to set your PYTHONPATH environment variable:

$ git clone https://github.com/redislabs-training/ru101.git
$ cd ru101
$ export PYTHONPATH=`pwd`
$ python3 -m venv venv
$ . venv/bin/activate
$ pip install -r requirements.txt

Configuration

The data loader and sample code expect Redis to be running at localhost:6379 with no password set. This is the default, but if your Redis instance uses a different hostname, port, or has a password, you should set the appropriate environment variables:

$ export REDIS_HOST=myredishost
$ export REDIS_PORT=9999
$ export REDIS_PASSWORD=ssssh

Network Latency

Running the Redis server and the Python code on different machines introduces round trip network latency for each Redis command sent from Python to Redis. To keep the example code simple, some of the Python scripts for this course send each command to Redis separately.

To get the most performance from applications using Redis, we recommend the use of pipelining to send multiple commands to the server in a single round trip where possible. You should also ensure that the application code and Redis server are on hosts with minimal latency between them. These concepts are covered in more detail in the following programming language specific Redis University courses:

• RU102J Redis for Java Developers
• RU102JS Redis for JavaScript Developers
• RU102PY Redis for Python Developers
• RU102N Redis for .NET Developers

To get the best performance from the simple demo scripts for this course, you should run the code and the Redis server on the same local network or the same machine if possible.

Loading the Sample Data

To answer some of the homework and exam questions, and to run the sample code, you'll need to load the sample data into Redis. Skip this step if you chose to use a Cloud Redis Stack instance as you will have loaded the data as part of the database setup.

If you're running Redis Stack locally or via Docker, go ahead and load the data as follows:

$ cd redisu
$ python utils/dumpload.py load ru101/data/ru101.json

If the sample data was loaded correctly, you should see the following message:

total keys loaded: 14328

Using redis-cli

Some of the quiz, homework and exam questions for this course may require you to use the Redis command line interface to execute commands. Start redis-cli from the command line as follows:

$ redis-cli
127.0.0.1:6379>

You can then enter Redis commands, for example to see how many keys are in the database use dbsize:

127.0.0.1:6379> dbsize
(integer) 14328
127.0.0.1:6379>

If you prefer a more graphical user interface, try RedisInsight, a free tool for exploring and interacting with Redis that includes an embedded redis-cli.

Running the Code

To run the example code, cd to the directory containing the script you wish to run, and pass the script name to the python command.

Example:

$ cd redisu/ru101/uc01-faceted-search
$ python search.py

Need Help or Have Questions?

If you need help, have questions, or want to chat about all things Redis, please join us on the Redis University Discord Server.

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