Redis on ubuntu 16

Article taken from: https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-redis-on-ubuntu-16-04 Placed here for my own reference.

Introduction

Redis is an in-memory key-value store known for its flexibility, performance, and wide language support. In this guide, we will demonstrate how to install and configure Redis on an Ubuntu 16.04 server.

Prerequisites

To complete this guide, you will need access to an Ubuntu 16.04 server. You will need a non-root user with sudo privileges to perform the administrative functions required for this process. You can learn how to set up an account with these privileges by following our Ubuntu 16.04 initial server setup guide.

When you are ready to begin, log in to your Ubuntu 16.04 server with your sudo user and continue below.

Install the Build and Test Dependencies

In order to get the latest version of Redis, we will be compiling and installing the software from source. Before we download the code, we need to satisfy the build dependencies so that we can compile the software.

To do this, we can install the build-essential meta-package from the Ubuntu repositories. We will also be downloading the tcl package, which we can use to test our binaries.

We can update our local apt package cache and install the dependencies by typing:

Download, Compile, and Install Redis

Next, we can begin to build Redis.

Download and Extract the Source Code

Since we won’t need to keep the source code that we’ll compile long term (we can always re-download it), we will build in the /tmp directory. Let’s move there now:

 

Now, download the latest stable version of Redis. This is always available at a stable download URL:

 

Unpack the tarball by typing:

Move into the Redis source directory structure that was just extracted:

Build and Install Redis

Now, we can compile the Redis binaries by typing:

 

After the binaries are compiled, run the test suite to make sure everything was built correctly. You can do this by typing:

 

This will typically take a few minutes to run. Once it is complete, you can install the binaries onto the system by typing:

Configure Redis

Now that Redis is installed, we can begin to configure it.

To start off, we need to create a configuration directory. We will use the conventional /etc/redis directory, which can be created by typing:

Now, copy over the sample Redis configuration file included in the Redis source archive:

Next, we can open the file to adjust a few items in the configuration:

In the file, find the supervised directive. Currently, this is set to no. Since we are running an operating system that uses the systemd init system, we can change this to systemd:

/etc/redis/redis.conf

Next, find the dir directory. This option specifies the directory that Redis will use to dump persistent data. We need to pick a location that Redis will have write permission and that isn’t viewable by normal users.

We will use the /var/lib/redis directory for this, which we will create in a moment:

/etc/redis/redis.conf

Save and close the file when you are finished.

Create a Redis systemd Unit File

Next, we can create a systemd unit file so that the init system can manage the Redis process.

Create and open the /etc/systemd/system/redis.service file to get started:

Inside, we can begin the [Unit] section by adding a description and defining a requirement that networking be available before starting this service:

/etc/systemd/system/redis.service

In the [Service] section, we need to specify the service’s behavior. For security purposes, we should not run our service as root. We should use a dedicated user and group, which we will call redis for simplicity. We will create these momentarily.

To start the service, we just need to call the redis-server binary, pointed at our configuration. To stop it, we can use the Redis shutdown command, which can be executed with the redis-cli binary. Also, since we want Redis to recover from failures when possible, we will set the Restart directive to “always”:

/etc/systemd/system/redis.service

Finally, in the [Install] section, we can define the systemd target that the service should attach to if enabled (configured to start at boot):

/etc/systemd/system/redis.service

Save and close the file when you are finished.

Create the Redis User, Group and Directories

Now, we just have to create the user, group, and directory that we referenced in the previous two files.

Begin by creating the redis user and group. This can be done in a single command by typing:

Now, we can create the /var/lib/redis directory by typing:

We should give the redis user and group ownership over this directory:

Adjust the permissions so that regular users cannot access this location:

Start and Test Redis

Now, we are ready to start the Redis server.

Start the Redis Service

Start up the systemd service by typing:

Check that the service had no errors by running:

You should see something that looks like this:

Output

 

Test the Redis Instance Functionality

To test that your service is functioning correctly, connect to the Redis server with the command-line client:

In the prompt that follows, test connectivity by typing:

You should see:

Exit the Redis prompt to get back to the shell:

As a final test, let’s restart the Redis instance:

 

Enable Redis to Start at Boot

If all of your tests worked, and you would like to start Redis automatically when your server boots, you can enable the systemd service.

To do so, type:

Output

Created symlink from /etc/systemd/system/multi-user.target.wants/redis.service to /etc/systemd/system/redis.service.

Webpack – SASS – Bootstrap-sass

In a previous post I put together a sass compiling webpack file… http://www.beingyesterday.com/webpack-and-sass/

But you will run into more fun and games if you want to use bootstrap-sass with this. The fun being more like a headache actually.

Anyway… if you add bootstrap-sass as an include in any of your .scss files the result will be that webpack cannot load/process any of the fonts. To get around this we need a new webpack loader and a new dev dependency in the package.json:

The extra loader above creates the rel. files in a /font directory.

 

The additional loader also requires the ‘url-loader’ adding to the package.json

 

Webpack and sass

 

What is going on above:

  1. We set an entry point for webpack named ‘stylesheet’ to the exact path to our .scss file.
  2. We define an output path, which in this case is redundant as we only want the css but webpack needs an output.
  3. As we need an actual .css file written to disk we use the ‘ExtractTextPlugin’ pluggin where the first parameter is the path to the css output file. Note the [name] bit.. this is not at all required and the [name] will be replaced with the entry key, which in this case is ‘stylesheet’. The end output for the css should be ‘/css/stylesheet.css’. You can just as easily replace [name] with whatever you wanted.
  4. In the loaders section of the modules, we write a test for .scss files and for the loader we simply pass the function

To get all actually running of course we need a couple of additions to our package.json file:

 

We can now also watch too with –watch…

 

(if you are using bootstrap-sass too.. you will need a few more goodies in the mix… http://www.beingyesterday.com/webpack-sass-bootstrap-sass/)