Host your own web app on a Raspberry Pi Part 2

The external port (range) is the port you want your website to be available on. For websites, the standard port is 80. The internal port range is the port your webserver – in this case Apache - is running on your local RaspberryPi. If you didn’t change anything in the setup from Part 1 of this tutorial, this should also be Port 80. The internal IP address is the IP of your Pi on your local network.

Dollar bills, Dollar bills - purchase a domain

If you want to access a website, normally you key in a name in your browser (actually, most of the time one just googles for the site), you don’t want to remember a IP address of a website. This is when a domain comes in handy. A domain is basically a unique identifier which links to the IP address of your network resource – in this case our public IP address. 

After this step, you can choose a plan – for our needs, the free plan is sufficient:

After confirming your free plan, cloudflare automatically scans all DNS entries for your domain. You can check the results of the scan and add entries if it’s not correct or complete.

wally.ns.cloudflare.com

oswald.ns.cloudflare.com

Please keep in mind that the DNS changes take some time to be published through all major DNS servers. It can take up to 24hours.

Overview > Get your API key > Global API Key in the cloudflare backend and store your API key to a safe place. 

$ nano updateIpCloudflare.sh

#!/bin/bash

# CHANGE THESE
auth_email="[email protected]"
auth_key="yourCloudFlareAPIKey"
zone_name="aboe.eu"
record_name="aboe.eu"

ip=$(curl -s http://ipv4.icanhazip.com)
echo $ip
ip_file="ip.txt"
id_file="cloudflare.ids"
log_file="cloudflare.log"

# LOGGER
log() {
    if [ "$1" ]; then
        echo -e "[$(date)] - $1" >> $log_file
    fi
}

# SCRIPT START
log "Check Initiated"

if [ -f $ip_file ]; then
    old_ip=$(cat $ip_file)
    if [ $ip == $old_ip ]; then
        echo "IP has not changed."
        exit 0
    fi
fi

if [ -f $id_file ] && [ $(wc -l $id_file | cut -d " " -f 1) == 2 ]; then
    zone_identifier=$(head -1 $id_file)
    record_identifier=$(tail -1 $id_file)
else
    zone_identifier=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$zone_name" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json" | grep -Po '(?<="id":")[^"]*' | head -1 )
    record_identifier=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records?name=$record_name" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json"  | grep -Po '(?<="id":")[^"]*')
    echo "$zone_identifier" > $id_file
    echo "$record_identifier" >> $id_file
fi

update=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records/$record_identifier" -H "X-Auth-Email: $auth_email" -H "X-Auth-Key: $auth_key" -H "Content-Type: application/json" --data "{\"id\":\"$zone_identifier\",\"type\":\"A\",\"name\":\"$record_name\",\"content\":\"$ip\"}")

if [[ $update == *"\"success\":false"* ]]; then
    message="API UPDATE FAILED. DUMPING RESULTS:\n$update"
    log "$message"
    echo -e "$message"
    exit 1
else
    message="IP changed to: $ip"
    echo "$ip" > $ip_file
    log "$message"
    echo "$message"
fi

$ chmod +x updateIpCloudflare.sh

# CHANGE THESE
auth_email="[email protected]"
auth_key="yourCloudFlareAPIKey"
zone_name="aboe.eu"
record_name="aboe.eu"

$ ./updateIpCloudflare.sh

10.10.215.10

IP changed to: 10.10.215.10

$ less cloudflare.log

[Thu May 14 13:06:46 BST 2020] - Check Initiated

[Thu May 14 13:06:47 BST 2020] - IP changed to: 10.10.215.10

http://my-domain.com

One last thing

You probably already noticed, but we only started our updateIpCloudflare.sh script manually and it wouldn’t recognize if our IP has changed. This is why we need to run the script periodically. The easiest way to do this is via a cronjob.
Open the crontab and add the following line to the end of the file:

$ sudo crontab -e

*/10 *    * * *   /home/pi/updateIpCloudflare.sh > /dev/null 2>&1