Update readme

Author: Programie

README.md

@@ -7,57 +7,57 @@
 
 PHP DynDNS is a very simple DynDNS service. It allows you to update your DNS server via a simple HTTP request.
 
-Authorization is done using HTTP Basic Auth or using the *username* and *password* URL variables.
+Authorization is done using HTTP Basic Auth or using the `username` and `password` URL variables.
 
-The full URL looks like *https://dyndns.example.com/?hostname=myhost.example.com* (HTTP Basic Auth) or *https://dyndns.example.com/?hostname=myhost.example.com&username=myuser&password=mypassword* (URL variable auth).
+The full URL looks like `https://dyndns.example.com/?hostname=myhost.example.com` (HTTP Basic Auth) or `https://dyndns.example.com/?hostname=myhost.example.com&username=myuser&password=mypassword` (URL variable auth).
 
-You may also specify the IPv4 and IPv6 address using GET variables (myip=your.ipv4.address.here and myipv6=your:ipv6:address:here).
+You may also specify the IPv4 and IPv6 address using GET variables (`myip=your.ipv4.address.here` and `myipv6=your:ipv6:address:here`).
 
 Examples:
 
-* IPv4 only: https://dyndns.example.com/?hostname=myhost.example.com&myip=79.206.99.18
-* IPv6 only: https://dyndns.example.com/?hostname=myhost.example.com&myipv6=2003:66:ef5d:9300:5899:991b:8542:b19f
-* IPv4 + IPv6: https://dyndns.example.com/?hostname=myhost.example.com&myip=79.206.99.18&myipv6=2003:66:ef5d:9300:5899:991b:8542:b19f
+* IPv4 only: `https://dyndns.example.com/?hostname=myhost.example.com&myip=79.206.99.18`
+* IPv6 only: `https://dyndns.example.com/?hostname=myhost.example.com&myipv6=2003:66:ef5d:9300:5899:991b:8542:b19f`
+* IPv4 + IPv6: `https://dyndns.example.com/?hostname=myhost.example.com&myip=79.206.99.18&myipv6=2003:66:ef5d:9300:5899:991b:8542:b19f`
 
 ## Requirements
 
    * A domain
    * A web server running PHP 7.2 or newer
    * A DNS server (e.g. bind)
 
-Or use the ready to run Docker image (see section "Installation using Docker")
+Or use the ready to run Docker image (see section [Installation using Docker](#installation-using-docker)).
 
 ## Installation
 
 There are two methods for getting the latest release:
 
-* (recommended) Download the [latest release](https://github.com/Programie/PHPDynDNS/releases/latest) and extract it to your web directory from where you want to serve the files (e.g. /var/www/dyndns)
-* Clone this repository to your web directory from where you want to serve the files (e.g. /var/www/dyndns)
+* (recommended) Download the [latest release](https://github.com/Programie/PHPDynDNS/releases/latest) and extract it to your web directory from where you want to serve the files (e.g. `/var/www/dyndns`)
+* Clone this repository to your web directory from where you want to serve the files (e.g. `/var/www/dyndns`)
 
 Directly cloning the repository requires you to download the required dependencies using [Composer](https://getcomposer.org): `composer install`
 
 Once downloaded, continue with the following steps:
 
-* Copy *config.sample.json* to *config.json*
-* Edit config.json to fit your needs (see [Configuration section](#configuration) bellow for details)
+* Copy `config.sample.json` to `config.json`
+* Edit `config.json` to fit your needs (see [Configuration section](#configuration) bellow for details)
 * Configure your DNS server to allow update requests from the webserver (e.g. `allow-update { localhost; }` in bind)
 * [Configure your router](#configure-your-router) to automatically request the URL of your DynDNS service after each reconnect (or create a cronjob with curl/wget).
 
 ## Installation using Docker
 
 PHPDynDNS is also provided as a Docker image. Just pull it from [Docker Hub](https://hub.docker.com/r/programie/phpdyndns).
 
-Mount your config.json to */app/config.json*
+Mount your `config.json` to `/app/config.json`
 
 Example command to start the container:
 
-```
+```bash
 docker run -d --name phpdyndns -p 80:80 -v /path/to/config.json:/app/config.json:ro programie/phpdyndns
 ```
 
 ## Important
 
-Make sure the config.json is not readable via HTTP! On Apache this is already done using the *.htaccess* file.
+Make sure the config.json is not readable via HTTP! On Apache this is already done using the `.htaccess` file.
 
 ## Configuration
 
@@ -86,22 +86,22 @@ The configuration is done using JSON stored in the `config.json` file which look
 
 ### Properties
 
-* **server**: The DNS server to connect to (default: `localhost`)
-* **ttl**: The TTL (time to live) for all DNS entries managed by PHPDynDNS (default: `60`)
-* **users**: A map listing all users (the key of each entry is the username)
-   * **password_hash**: The hashed password of the user (e.g. created with `mkpasswd -m sha-256`)
-   * **hosts**: A map listing all hosts this user is able to update (the key of each entry is the hostname to update)
-      * **zone**: The zone which contains this hostname
-   * **post_process**: A command which should be executed after successfully updating the DNS entry (can contain placeholders, see note below)
+* `server`: The DNS server to connect to (default: `localhost`)
+* `ttl`: The TTL (time to live) for all DNS entries managed by PHPDynDNS (default: `60`)
+* `users`: A map listing all users (the key of each entry is the username)
+   * `password_hash`: The hashed password of the user (e.g. created with `mkpasswd -m sha-256`)
+   * `hosts`: A map listing all hosts this user is able to update (the key of each entry is the hostname to update)
+      * `zone`: The zone which contains this hostname
+   * `post_process`: A command which should be executed after successfully updating the DNS entry (can contain placeholders, see note below)
 
 ### Placeholders for post_process option
 
 There are a few placeholders which can be used in the `post_process` option to be replaced on execution.
 
-* **%username%**: The username
-* **%hostname%**: The hostname
-* **%ipv4address%**: The new IPv4 address (if available)
-* **%ipv6address%**: The new IPv6 address (if available)
+* `%username%`: The username
+* `%hostname%`: The hostname
+* `%ipv4address%`: The new IPv4 address (if available)
+* `%ipv6address%`: The new IPv6 address (if available)
 
 ## Configure your router
 
@@ -120,6 +120,7 @@ Use this variant if your router does not support sending updates to (custom) Dyn
 ```
 * * * * * curl https://your.domain/path/to/phpdyndns?username=your-username&password=your-password&hostname=your.domain.tld
 ```
+
 This will update your domain `your.domain.tld` every minute.
 
 Replace `your-username`, `your-password` and `your.domain.tld` with your configured username, password and domain.
@@ -128,22 +129,22 @@ Replace `your-username`, `your-password` and `your.domain.tld` with your configu
 
 PHP DynDNS can trigger user defined commands after the DynDNS hostname has been updated successfully.
 
-A command might be "/opt/reload-iptables.sh" which automatically reloads iptables using the new IP-Address of the DynDNS hostname.
+A command might be `/opt/reload-iptables.sh` which automatically reloads iptables using the new IP-Address of the DynDNS hostname.
 
-The post processing command can be individually configured for each user in the config.json.
+The post-processing command can be individually configured for each user in the `config.json`.
 
 ### Example: Dynamic firewall using iptables
 
 PHP DynDNS can execute commands after the hostname has been updated successfully. And such a command might reload your iptables rules from a file which also forces iptables to re-lookup your dynamic hostname.
 
-The post processing script might look like the following:
+The post-processing script might look like the following:
 
 ```sh
 #! /bin/sh
 /sbin/iptables-restore < /path/to/your/iptables.rules
 ```
 
-The iptables.rules might look like the following:
+The `iptables.rules` might look like the following:
 
 ```
 *filter
@@ -172,4 +173,4 @@ The iptables.rules might look like the following:
 COMMIT
 ```
 
-**Note:** You have to call the script with root permissions (e.g. sudo)! Simply allow the user running the webserver (e.g. www-data) to execute the script as root (e.g. add *www-data ALL=(ALL) NOPASSWD:/opt/scripts/update_dyndns_iptables.sh* to your /etc/sudoers file).
+**Note:** You have to call the script with root permissions (e.g. sudo)! Simply allow the user running the webserver (e.g. www-data) to execute the script as root (e.g. add `www-data ALL=(ALL) NOPASSWD:/opt/scripts/update_dyndns_iptables.sh` to your `/etc/sudoers` file).