Add global variable for accessing the proxy settings in pipelines

src/main/java/org/jenkinsci/plugins/workflow/steps/HttpProxyEnvStep.java

@@ -0,0 +1,110 @@
+package org.jenkinsci.plugins.workflow.steps;
+
+import com.google.common.base.Joiner;
+import hudson.EnvVars;
+import hudson.Extension;
+import hudson.ProxyConfiguration;
+import jenkins.model.Jenkins;
+import org.kohsuke.stapler.DataBoundConstructor;
+
+import javax.annotation.Nonnull;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.Proxy;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+import java.util.regex.Pattern;
+
+/**
+ * @author Robin Müller
+ */
+public class HttpProxyEnvStep extends Step {
+
+    @DataBoundConstructor
+    public HttpProxyEnvStep() {
+    }
+
+    @Override
+    public StepExecution start(StepContext context) throws Exception {
+        return new Execution(context);
+    }
+
+    @Extension
+    public static class DescriptorImpl extends StepDescriptor {
+
+        @Override
+        public String getFunctionName() {
+            return "withHttpProxyEnv";
+        }
+
+        @Override
+        public boolean takesImplicitBlockArgument() {
+            return true;
+        }
+
+        @Override
+        public String getDisplayName() {
+            return "Set the global proxy settings as environment variables within a block";
+        }
+
+        @Override
+        public Set<? extends Class<?>> getRequiredContext() {
+            return Collections.emptySet();
+        }
+
+    }
+
+    public static class Execution extends AbstractStepExecutionImpl {
+
+        private static final long serialVersionUID = 1;
+
+        Execution(StepContext context) {
+            super(context);
+        }
+
+        @Override
+        public boolean start() throws Exception {
+            StepContext context = getContext();
+            context.newBodyInvoker()
+                   .withContext(EnvironmentExpander.merge(context.get(EnvironmentExpander.class), new HttpProxyEnvironmentExpander()))
+                   .withCallback(BodyExecutionCallback.wrap(context))
+                   .start();
+            return false;
+        }
+
+        @Override
+        public void stop(Throwable cause) throws Exception {
+            getContext().onFailure(cause);
+        }
+
+        @Override
+        public void onResume() {
+        }
+
+    }
+
+    private static class HttpProxyEnvironmentExpander extends EnvironmentExpander {
+        @Override
+        public void expand(@Nonnull EnvVars envVars) throws IOException, InterruptedException {
+            ProxyConfiguration proxyConfiguration = Jenkins.getActiveInstance().proxy;
+            if (proxyConfiguration != null) {
+                Proxy proxy = proxyConfiguration.createProxy(null);
+                InetSocketAddress address = (InetSocketAddress) proxy.address();
+                String proxyHost = "http://" + address.getHostName() + ":" + address.getPort();
+                envVars.put("http_proxy", proxyHost);
+                envVars.put("https_proxy", proxyHost);
+                envVars.put("HTTP_PROXY", proxyHost);
+                envVars.put("HTTPS_PROXY", proxyHost);
+                List<String> noProxyHosts = new ArrayList<>();
+                for (Pattern noProxyHost : proxyConfiguration.getNoProxyHostPatterns()) {
+                    noProxyHosts.add(noProxyHost.toString().replace("\\.", ".").replace(".*", "*"));
+                }
+                String noProxy = Joiner.on(',').join(noProxyHosts);
+                envVars.put("no_proxy", noProxy);
+                envVars.put("NO_PROXY", noProxy);
+            }
+        }
+    }
+}

src/main/resources/org/jenkinsci/plugins/workflow/steps/HttpProxyEnvStep/help.jelly

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<?jelly escape-by-default='true'?>
+<j:jelly xmlns:j="jelly:core">
+  Provides the global proxy settings as HTTP proxy environment variables<br/>
+  <ul>
+    <li>http_proxy/HTTP_PROXY</li>
+    <li>https_proxy/HTTPS_PROXY</li>
+    <li>no_proxy/NO_PROXY</li>
+  </ul>
+</j:jelly>

src/test/java/org/jenkinsci/plugins/workflow/steps/HttpProxyEnvStepTest.java

@@ -0,0 +1,66 @@
+package org.jenkinsci.plugins.workflow.steps;
+
+import hudson.ProxyConfiguration;
+import hudson.model.Result;
+import org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition;
+import org.jenkinsci.plugins.workflow.job.WorkflowJob;
+import org.jenkinsci.plugins.workflow.job.WorkflowRun;
+import org.junit.Rule;
+import org.junit.Test;
+import org.jvnet.hudson.test.JenkinsRule;
+
+/**
+ * @author Robin Müller
+ */
+public class HttpProxyEnvStepTest {
+
+    @Rule
+    public JenkinsRule jenkinsRule = new JenkinsRule();
+
+    @Test
+    public void test_proxy_not_set() throws Exception {
+        WorkflowJob job = jenkinsRule.jenkins.createProject(WorkflowJob.class, "workflow");
+        job.setDefinition(new CpsFlowDefinition("withHttpProxyEnv { " +
+                                                "  echo \"proxy: $env.http_proxy\" " +
+                                                "}", true));
+
+        WorkflowRun run = jenkinsRule.assertBuildStatus(Result.SUCCESS, job.scheduleBuild2(0).get());
+        jenkinsRule.assertLogContains("proxy: null", run);
+    }
+
+    @Test
+    public void test_proxy_set() throws Exception {
+        jenkinsRule.getInstance().proxy = new ProxyConfiguration("test", 8080);
+
+        WorkflowJob job = jenkinsRule.jenkins.createProject(WorkflowJob.class, "workflow");
+        job.setDefinition(new CpsFlowDefinition("withHttpProxyEnv { " +
+                                                "  echo \"proxy: $env.http_proxy\" " +
+                                                "}", true));
+        WorkflowRun run = jenkinsRule.assertBuildStatus(Result.SUCCESS, job.scheduleBuild2(0).get());
+        jenkinsRule.assertLogContains("proxy: http://test:8080", run);
+    }
+
+    @Test
+    public void test_noProxyHosts_not_set() throws Exception {
+        WorkflowJob job = jenkinsRule.jenkins.createProject(WorkflowJob.class, "workflow");
+        job.setDefinition(new CpsFlowDefinition("withHttpProxyEnv { " +
+                                                "  echo \"noProxyHosts: $env.no_proxy\" " +
+                                                "}", true));
+
+        WorkflowRun run = jenkinsRule.assertBuildStatus(Result.SUCCESS, job.scheduleBuild2(0).get());
+        jenkinsRule.assertLogContains("noProxyHosts: null", run);
+    }
+
+    @Test
+    public void test_noProxyHosts_set() throws Exception {
+        jenkinsRule.getInstance().proxy = new ProxyConfiguration("test", 8080, null, null, "test.tld\n*.test.tld");
+
+        WorkflowJob job = jenkinsRule.jenkins.createProject(WorkflowJob.class, "workflow");
+        job.setDefinition(new CpsFlowDefinition("withHttpProxyEnv { " +
+                                                "  echo \"noProxyHosts: $env.no_proxy\" " +
+                                                "}", true));
+
+        WorkflowRun run = jenkinsRule.assertBuildStatus(Result.SUCCESS, job.scheduleBuild2(0).get());
+        jenkinsRule.assertLogContains("noProxyHosts: test.tld,*.test.tld", run);
+    }
+}