Support for IP Ranges in NO_PROXY Environment Variable

[PasternakDominik]

Describe the feature

I would like to request an enhancement to support the parsing of IP ranges (e.g., CIDR notation such as 172.16.0.0/12) in the NO_PROXY environment variable. This feature will significantly enhance the flexibility and usability of the SDK in various network environments.

Use Case

In many enterprise environments, it is common to have internal network ranges that should bypass proxy settings. Currently, the NO_PROXY environment variable supports specifying individual IP addresses or hostnames, but does not natively support CIDR notation for specifying IP ranges. Supporting CIDR notation would allow users to easily configure the SDK to bypass proxies for entire subnets, simplifying configuration and reducing the risk of misconfiguration.

For example:

• Setting NO_PROXY=172.16.0.0/12 should allow the SDK to bypass the proxy for any IP address within the 172.16.0.0 to 172.31.255.255 range.

[debora-ito]

@PasternakDominik which application you're using that supports IP range in NO_PROXY environment variable currently?

I'm asking because we would like to support the same format in the system property, but Java NO_PROXY format is already established as a list of hosts - reference: https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/net/doc-files/net-properties.html

Also, I'd have to raise this as a cross-SDK feature, to have a standard support across all SDKs.

[PasternakDominik]

Hello @debora-ito

Thank you for considering this feature!

Currently, I'm using Docker for GitLab Runners that support the use of IP ranges in the NO_PROXY environment variable. As far as I know, the applications/systems that also support this format are:

• curl
• wget
• and probably all networking tools :)