I have recently begun building an Angular Ionic app which connects to PHP scripts on an AWS EC2 server. Everything works fine except for when I try to connect through Android once the app is built on my phone.
The response is a simple 404 response with no additional information. When I look at the log on Android Studio I see the following response:
E/Capacitor: Unable to open asset URL: [api address]
I have reduced both the HttpClient call on the frontend and the php file on the backend to their most simple forms and yet still nothing:
<?php
echo "Hello";
?>
I know that Capacitor was updated to 3 only a couple of months ago and am concerned that it is related to that. I am using PHP 7.
UPDATE The issue was indeed cleartext but the issue was made more complicated by the fact that HttpClient was not catching the error and so I was simply getting back an unknown failed response.
In order to first see that it was cleartext I first had to change HttpClient for the Native HTTP plugin and check the logs whilst testing on my phone (HTTP will not work through the browser).
Only then did I notice that I hadn't changed the config file correctly.
As long as your PHP web server is not running on the Android device directly trying to connect to localhost / 127.0.0.1 won't work and you need to use another domain / IP your web server is available on and which the Android device can access. You can also check this by simply opening the URL in the browser of the Android device.
If that is not feasible for you you could also use port forwarding via adb to forward a port of your web server to a local port on the Android device.
If you use another domain / IP make sure your web server is not listening to local connections only and is not blocked by a firewall or similar.
Also if you are using an unencrypted connection (i.e. http instead of https) you might need to enable the cleartext config option in you Capacitor config.