Add useSystemProperties() to HttpClientBuilder for proxy support (#1088)

Enable JVM system property-based proxy configuration (http.proxyHost,
https.proxyHost, http.nonProxyHosts, etc.) so environments like OpenShift
can route HTTP traffic through a corporate proxy via JAVA_TOOL_OPTIONS
without code changes.

Co-authored-by: g-gallotti_globant <g.gallotti@globant.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: 3 people

java/src/main/java/com/genexus/internet/HttpClientJavaLib.java

@@ -102,6 +102,7 @@ public HttpClientJavaLib() {
 		HttpClientBuilder builder = HttpClients.custom()
 			.setConnectionManager(connManager)
 			.setConnectionManagerShared(true)
+			.useSystemProperties()
 			.setKeepAliveStrategy(myStrategy);
 		if (getGxIpResolverConfig() != null) {
 			builder.setDnsResolver(new FirstIpDnsResolver());

java/src/test/java/com/genexus/internet/TestHttpClientProxy.java

@@ -0,0 +1,140 @@
+package com.genexus.internet;
+
+import com.genexus.Application;
+import com.genexus.sampleapp.GXcfg;
+import com.genexus.specific.java.Connect;
+import com.genexus.specific.java.LogManager;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+public class TestHttpClientProxy {
+
+	private static final String PROXY_HOST_PROP = "http.proxyHost";
+	private static final String PROXY_PORT_PROP = "http.proxyPort";
+	private static final String HTTPS_PROXY_HOST_PROP = "https.proxyHost";
+	private static final String HTTPS_PROXY_PORT_PROP = "https.proxyPort";
+	private static final String NON_PROXY_HOSTS_PROP = "http.nonProxyHosts";
+
+	private String origHttpProxyHost;
+	private String origHttpProxyPort;
+	private String origHttpsProxyHost;
+	private String origHttpsProxyPort;
+	private String origNonProxyHosts;
+
+	@Before
+	public void setUp() throws Exception {
+		Connect.init();
+		Application.init(GXcfg.class);
+		LogManager.initialize(".");
+
+		origHttpProxyHost = System.getProperty(PROXY_HOST_PROP);
+		origHttpProxyPort = System.getProperty(PROXY_PORT_PROP);
+		origHttpsProxyHost = System.getProperty(HTTPS_PROXY_HOST_PROP);
+		origHttpsProxyPort = System.getProperty(HTTPS_PROXY_PORT_PROP);
+		origNonProxyHosts = System.getProperty(NON_PROXY_HOSTS_PROP);
+	}
+
+	@After
+	public void tearDown() {
+		restoreProperty(PROXY_HOST_PROP, origHttpProxyHost);
+		restoreProperty(PROXY_PORT_PROP, origHttpProxyPort);
+		restoreProperty(HTTPS_PROXY_HOST_PROP, origHttpsProxyHost);
+		restoreProperty(HTTPS_PROXY_PORT_PROP, origHttpsProxyPort);
+		restoreProperty(NON_PROXY_HOSTS_PROP, origNonProxyHosts);
+	}
+
+	private void restoreProperty(String key, String originalValue) {
+		if (originalValue == null) {
+			System.clearProperty(key);
+		} else {
+			System.setProperty(key, originalValue);
+		}
+	}
+
+	@Test
+	public void httpRequestUsesProxyFromSystemProperties() {
+		// Set proxy to a non-existent proxy server (localhost on an unlikely port).
+		// If the client respects the system property, it will try to connect through
+		// this proxy and fail, resulting in a non-200 status code.
+		System.setProperty(PROXY_HOST_PROP, "127.0.0.1");
+		System.setProperty(PROXY_PORT_PROP, "19999");
+
+		HttpClientJavaLib httpClient = new HttpClientJavaLib();
+		httpClient.setTimeout(1);
+		httpClient.execute("GET", "http://www.google.com/");
+
+		// The request should fail because it tried to route through the non-existent proxy
+		Assert.assertNotEquals("Request should fail when routed through non-existent proxy",
+			200, httpClient.getStatusCode());
+	}
+
+	@Test
+	public void httpsRequestUsesProxyFromSystemProperties() {
+		// Set HTTPS proxy to a non-existent proxy server
+		System.setProperty(HTTPS_PROXY_HOST_PROP, "127.0.0.1");
+		System.setProperty(HTTPS_PROXY_PORT_PROP, "19999");
+
+		HttpClientJavaLib httpClient = new HttpClientJavaLib();
+		httpClient.setTimeout(1);
+		httpClient.execute("GET", "https://www.google.com/");
+
+		// The request should fail because it tried to route through the non-existent proxy
+		Assert.assertNotEquals("HTTPS request should fail when routed through non-existent proxy",
+			200, httpClient.getStatusCode());
+	}
+
+	@Test
+	public void requestSucceedsWithoutProxySystemProperties() {
+		// Ensure no proxy system properties are set
+		System.clearProperty(PROXY_HOST_PROP);
+		System.clearProperty(PROXY_PORT_PROP);
+		System.clearProperty(HTTPS_PROXY_HOST_PROP);
+		System.clearProperty(HTTPS_PROXY_PORT_PROP);
+
+		HttpClientJavaLib httpClient = new HttpClientJavaLib();
+		httpClient.setTimeout(1);
+		httpClient.execute("GET", "https://www.google.com/");
+
+		// Without proxy, direct connection should succeed
+		Assert.assertEquals("Direct request without proxy should succeed",
+			200, httpClient.getStatusCode());
+	}
+
+	@Test
+	public void explicitProxyOverridesSystemProperties() {
+		// Set system properties to a valid-looking proxy (that we won't actually hit)
+		System.setProperty(PROXY_HOST_PROP, "10.255.255.1");
+		System.setProperty(PROXY_PORT_PROP, "3128");
+
+		HttpClientJavaLib httpClient = new HttpClientJavaLib();
+		httpClient.setTimeout(1);
+
+		// Explicit proxy should take precedence over system properties
+		httpClient.setProxyServerHost("127.0.0.1");
+		httpClient.setProxyServerPort(19999);
+		httpClient.execute("GET", "http://www.google.com/");
+
+		// Should fail because the explicit proxy (127.0.0.1:19999) doesn't exist
+		Assert.assertNotEquals("Explicit proxy should be used instead of system property proxy",
+			200, httpClient.getStatusCode());
+	}
+
+	@Test
+	public void nonProxyHostsBypassesProxy() {
+		// Set proxy to a non-existent proxy
+		System.setProperty(HTTPS_PROXY_HOST_PROP, "127.0.0.1");
+		System.setProperty(HTTPS_PROXY_PORT_PROP, "19999");
+		// But exclude google.com from proxy
+		System.setProperty(NON_PROXY_HOSTS_PROP, "*.google.com");
+
+		HttpClientJavaLib httpClient = new HttpClientJavaLib();
+		httpClient.setTimeout(1);
+		httpClient.execute("GET", "https://www.google.com/");
+
+		// Should succeed because google.com is in the non-proxy list
+		Assert.assertEquals("Request to non-proxy host should bypass proxy and succeed",
+			200, httpClient.getStatusCode());
+	}
+}