Modify Android app to allow user-signed SSL certificates (such as Charles Proxy)

add_user_certificate_acceptance.sh

#!/bin/bash

# To use Charles Proxy with SSL: 
# (1) On the device, open a browser and visit https://chls.pro/ssl to download a security certificate
# (2) Open the certificate, and when it installs select "VPN and apps"
# (3) Open up wifi settings, under "Advanced" set the proxy address to your laptop's IP address, port 8888
# (4) Run this script from the app module before building the app so that it will allow proxying with a user-installed certificate (such as you installed in step (2))
#
# Don't forget to revert these changes when you're done if you don't mean to commit them. 

mkdir -p src/main/res/xml/

cat > src/main/res/xml/network_security_config.xml <<EOF
<network-security-config> 
  <debug-overrides> 
    <trust-anchors> 
      <!-- Trust user added CAs while debuggable only -->
      <certificates src="user" /> 
    </trust-anchors> 
  </debug-overrides> 
</network-security-config>
EOF

sed -i "" "/<application/ a\\		
		android:networkSecurityConfig='@xml/network_security_config'
" src/main/AndroidManifest.xml