Month: May 2018

Google Adsense for Wordpres – No Plugin Needed

Adding Google Adsense ads to your your WordPress blog was a tedious task. Either you needed to manually modify your theme, or you had to use a plugin, such as Google’s own Adsense plugin. Even then, placements were limited and handling both mobile and desktop themes was complicated at best. Recently, two things have changed: Google retired the Adsense plugin and introduced Auto Ads.

At first, the situation seemed like it turned for the worse. Without the official plugin, you had to resort into using a third-party plugin or manually placing ads in your theme. But Auto ads made things much simpler. Instead of having to manually place your ads, you can let Google do it for you. It works great on both desktop and mobile theme.

The easiest way to enable Auto ads is using a child theme. First, you need to get the Auto ads ad code. Next, in your child theme’s functions.php add the following lines, making sure to replace the javascript snippet with your own one.

// Add Google Adsense
function my_google_adsense_header() {
?>
<script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<script>
     (adsbygoogle = window.adsbygoogle || []).push({
          google_ad_client: "ca-pub-4066984350135216",
          enable_page_level_ads: true
     });
</script>
<?php
}
add_action( 'wp_head', 'my_google_adsense_header');

Google Analytics for WordPress

To set up Google Analytics tracking for WordPress you don’t need any third-party plugin. It can be easily done using a child theme. A child theme, is a code that modifies the current theme in a way that won’t interfere with future upgrades. To enable Google Analytics, start by creating a child theme using the official documentation.

Now, you need to get you Google Analytics tracking code. Over the years the tracking code had a few different versions. You should make sure you are getting the latest tracking code, which currently looks like:

<!-- Global site tag (gtag.js) - Google Analytics -->
<script async src="https://www.googletagmanager.com/gtag/js?id=UA-380837-9"></script>
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('js', new Date());

  gtag('config', 'UA-380837-9');
</script>

To get the tracking code, follow the instructions on this page.

Now we add the tracking code to each page using the child theme. In your child theme’s directory, edit the functions.php file and add the following lines. Replace the tracking code with the one you acquired.

// Add Google Analytics tracking
function my_google_analytics_header() {
?>
<!-- Global site tag (gtag.js) - Google Analytics -->
<script async src="https://www.googletagmanager.com/gtag/js?id=UA-380837-9"></script>
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('js', new Date());

  gtag('config', 'UA-380837-9');
</script>
<?php
}
add_action( 'wp_head', 'my_google_analytics_header');

This adds the tracking code to the <head> of every page.

Creating Local Backups using `rdiff-backup`

rdiff-backup provides an easy way to maintain reverse-incremental backups of your data. Reverse incremental backups are different from normal incremental backups by synthetically updating the full backup and keeping reverse diffs of all the files changed. It is best illustrated by an example. Let’s consider backups taken on three consecutive days:
1. Full backup (1st day).
2. Full backup (2nd day), reverse-diff: 2nd -> 1st.
3. Full backup (3rd day), reverse diffs: 3rd -> 2nd, 2nd -> 1st.

Compare that with the regular incremental backup model which would be:
1. Full backup (1st day).
2. Diff: 2nd -> 1st, full backup (1st day).
3. Diffs: 3rd -> 2nd, 2nd -> 1st, full backup (1st day).

This especially makes purging old backups easier. Reverse incremental backups allows you to simply purge the reverse-diffs as they expire. This happens because newer backups never depend on older ones. In contrast, in the regular incremental model, each incremental backup depends on each prior backup in the chain, going back to the full backups. Thus, you can’t remove the full backup until all the incremental backups that depend on it expire as well. This means that most of the time you need to keep more than one full backups, which takes up precious disk space.

rdiff-backup has some disadvantages as well:
1. Backups are not encrypted, making it unsuitable as-is for remote backups.
2. Only the reverse-diffs are compressed.

The advantages of rdiff-bakcup make it suitable to create local Time Machine-like backups.

The following script, set via cron to run daily, can be used to take backups of your home directory:

#! /bin/sh

SOURCE="/home/user/"
TARGET="/home/user/backups/rdiff-home/"

## Backup
rdiff-backup --exclude-if-present .nobackup --exclude-globbing-filelist /home/user/backups/home-exclude --print-statistics $SOURCE $TARGET

## Remove old data
rdiff-backup --remove-older-than 1M --force --print-statistics $TARGET

where `/home/user/backups/home-exclude should look like:

+ /home/user/Desktop
+ /home/user/Documents
+ /home/user/Music
+ /home/user/Pictures
+ /home/user/Videos
+ /home/user/.vim
+ /home/user/.vimrc
+ /home/user/.ssh
+ /home/user/.gnupg

**

In order to select only certain files and directories to backup.

The --exclude-if-present .nobackup allows you to easily add a .nobackup file to directories you wish to ignore. The --force argument when purging the old backups allows it to remove more than one expired backup in a single run.

Listing backup chains:

$ rdiff-backup -l ~/backups/rdiff-home/

Restoring files from the most recent backup is simple. Because rdiff-backup keeps the latest backup as a normal mirror on the disk, you can simply copy the file you need out of the backup directory. To restore older files:

$ rdiff-backup --restore-as-of 10D ~/backups/rdiff-home/.vimrc restored_vimrc