Backport proxyURL fix

patch instructions

README.md

@@ -1,3 +1,30 @@
+# NetObserv patch content
+
+This package is patched to allow JSON (de)serialization.
+
+Assuming you have "upstream" set as the prometheus upstream remote, and "netobserv" set as the netobserv patched remote, e.g:
+
+```bash
+$ git remote -v
+netobserv	git@github.com:netobserv/prometheus-common.git (fetch)
+netobserv	git@github.com:netobserv/prometheus-common.git (push)
+upstream	https://github.com/prometheus/common.git (fetch)
+upstream	https://github.com/prometheus/common.git (push)
+```
+
+Steps to rebase:
+
+```bash
+tag=v0.55.0 # the tag to rebase on
+git fetch upstream ; git fetch netobserv
+git reset --hard $tag
+git cherry-pick netobserv/main
+git tag -a "$tag-netobserv" -m "$tag-netobserv"
+git push netobserv HEAD:main
+git push netobserv --tags
+```
+
+
 # Common
 ![circleci](https://circleci.com/gh/prometheus/common/tree/main.svg?style=shield)
 

config/http_config.go

@@ -411,6 +411,10 @@ func (c *HTTPClientConfig) Validate() error {
 			return fmt.Errorf("at most one of oauth2 client_secret, client_secret_file & client_secret_ref must be configured")
 		}
 	}
+	// Change empty URL to nil to avoid connection errors
+	if c.ProxyURL.URL != nil && *c.ProxyURL.URL == (url.URL{}) {
+		c.ProxyURL.URL = nil
+	}
 	if err := c.ProxyConfig.Validate(); err != nil {
 		return err
 	}