Make your project accessible from the internet
The sipgate.io API cannot reach your project if the computer running it is behind a firewall. An easy way to circumvent this impediment is a tunnel service. Ngrok is easy to use and offers a free service which is sufficient for our needs. Download and run ngrok now, to make your project available from the internet.
Download ngrok for linux (amd64)
wget https://dl.ngrok.com/ngrok_2.0.17_linux_amd64.zip -O ngrok.zip
wget https://dl.ngrok.com/ngrok_2.0.17_darwin_amd64.zip -O ngrok.zip
./ngrok http 9000
Ngrok builds the tunnel and shows the newly generated tunnel url. This url changes with every restart of ngrok. In this example our project is reachable on https://12345678.ngrok.io/.