feat: generate config yaml to string for clients (#59)

Author: csviri

core/src/main/java/io/javaoperatorsdk/jenvtest/KubeAPIServer.java

@@ -4,6 +4,8 @@
 import org.slf4j.LoggerFactory;
 
 import io.javaoperatorsdk.jenvtest.binary.BinaryManager;
+import io.javaoperatorsdk.jenvtest.cert.CertManager;
+import io.javaoperatorsdk.jenvtest.kubeconfig.KubeConfig;
 import io.javaoperatorsdk.jenvtest.process.EtcdProcess;
 import io.javaoperatorsdk.jenvtest.process.KubeAPIServerProcess;
 import io.javaoperatorsdk.jenvtest.process.UnexpectedProcessStopHandler;
@@ -56,6 +58,10 @@ public void stop() {
     log.debug("Stopped");
   }
 
+  public String getKubeConfigYaml() {
+    return kubeConfig.generateKubeConfigYaml(kubeApiServerProcess.getApiServerPort());
+  }
+
   @Override
   public void processStopped(Process process) {
     stop();

core/src/main/java/io/javaoperatorsdk/jenvtest/Utils.java

@@ -58,6 +58,7 @@ public static int findFreePort() {
     try (ServerSocket socket = new ServerSocket(0)) {
       return socket.getLocalPort();
     } catch (IOException e) {
+
     }
     return -1;
   }

core/src/main/java/io/javaoperatorsdk/jenvtest/CertManager.java renamed to core/src/main/java/io/javaoperatorsdk/jenvtest/cert/CertManager.java

@@ -1,4 +1,4 @@
-package io.javaoperatorsdk.jenvtest;
+package io.javaoperatorsdk.jenvtest.cert;
 
 import java.io.File;
 import java.io.FileWriter;
@@ -27,6 +27,8 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import io.javaoperatorsdk.jenvtest.JenvtestException;
+
 public class CertManager {
 
   private static final Logger log = LoggerFactory.getLogger(CertManager.class);

core/src/main/java/io/javaoperatorsdk/jenvtest/KubeConfig.java renamed to core/src/main/java/io/javaoperatorsdk/jenvtest/kubeconfig/KubeConfig.java

@@ -1,21 +1,27 @@
-package io.javaoperatorsdk.jenvtest;
+package io.javaoperatorsdk.jenvtest.kubeconfig;
 
 import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
+import java.text.MessageFormat;
 import java.util.ArrayList;
 import java.util.List;
 
+import org.apache.commons.io.IOUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import io.javaoperatorsdk.jenvtest.JenvtestException;
 import io.javaoperatorsdk.jenvtest.binary.BinaryManager;
+import io.javaoperatorsdk.jenvtest.cert.CertManager;
 
 public class KubeConfig {
 
   private static final Logger log = LoggerFactory.getLogger(KubeConfig.class);
   public static final String JENVTEST = "jenvtest";
 
-  private CertManager certManager;
-  private BinaryManager binaryManager;
+  private final CertManager certManager;
+  private final BinaryManager binaryManager;
 
   public KubeConfig(CertManager certManager, BinaryManager binaryManager) {
     this.certManager = certManager;
@@ -47,6 +53,18 @@ private void unset(String target) {
     execWithKubectlConfigAndWait("unset", target);
   }
 
+  public String generateKubeConfigYaml(int apiServerPort) {
+    try (InputStream is = KubeConfig.class.getResourceAsStream("/kubeconfig-template.yaml")) {
+      String template = IOUtils.toString(is, StandardCharsets.UTF_8);
+      Object[] args = new Object[] {certManager.getAPIServerCertPath(),
+          apiServerPort, certManager.getClientCertPath(), certManager.getClientKeyPath()};
+      MessageFormat format = new MessageFormat(template);
+      return format.format(args);
+    } catch (IOException e) {
+      throw new JenvtestException(e);
+    }
+  }
+
   private void execWithKubectlConfigAndWait(String... arguments) {
     try {
       List<String> args = new ArrayList<>(arguments.length + 2);

core/src/main/java/io/javaoperatorsdk/jenvtest/process/KubeAPIServerProcess.java

@@ -25,6 +25,7 @@
 
 import io.javaoperatorsdk.jenvtest.*;
 import io.javaoperatorsdk.jenvtest.binary.BinaryManager;
+import io.javaoperatorsdk.jenvtest.cert.CertManager;
 
 import static io.javaoperatorsdk.jenvtest.KubeAPIServer.STARTUP_TIMEOUT;
 
@@ -211,4 +212,8 @@ public void stopApiServer() {
     }
     log.debug("API Server stopped");
   }
+
+  public int getApiServerPort() {
+    return apiServerPort;
+  }
 }

core/src/main/resources/kubeconfig-template.yaml

@@ -0,0 +1,20 @@
+apiVersion: v1
+clusters:
+  - cluster:
+      certificate-authority: {0}
+      server: https://127.0.0.1:{1,number,#}
+    name: jenvtest
+contexts:
+  - context:
+      cluster: jenvtest
+      namespace: default
+      user: jenvtest
+    name: jenvtest
+current-context: jenvtest
+kind: Config
+preferences: '{'}
+users:
+  - name: jenvtest
+    user:
+      client-certificate: {2}
+      client-key: {3}

core/src/test/java/io/javaoperatorsdk/jenvtest/binary/BinaryManagerTest.java

@@ -15,7 +15,6 @@ void throwsExceptionIfBinaryNotPresentAndInOfflineMode() {
         .withOfflineMode(true)
         .withApiServerVersion("1.0.1")
         .build());
-
     assertThrows(JenvtestException.class, binaryManager::initAndDownloadIfRequired);
   }
 

core/src/test/java/io/javaoperatorsdk/jenvtest/CertManagerTest.java renamed to core/src/test/java/io/javaoperatorsdk/jenvtest/cert/CertManagerTest.java

@@ -1,4 +1,4 @@
-package io.javaoperatorsdk.jenvtest;
+package io.javaoperatorsdk.jenvtest.cert;
 
 import java.io.File;
 import java.io.IOException;

core/src/test/java/io/javaoperatorsdk/jenvtest/kubeconfig/KubeConfigTest.java

@@ -0,0 +1,36 @@
+package io.javaoperatorsdk.jenvtest.kubeconfig;
+
+import org.junit.jupiter.api.Test;
+
+import io.javaoperatorsdk.jenvtest.cert.CertManager;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+class KubeConfigTest {
+
+  public static final String API_CERT_PATH = "~/.jenvtest/certpath";
+  public static final String CLIENT_KEY_PATH = "~/.jenvtest/clientcertkey";
+  public static final String CLIENT_CERT_PATH = "~/.jenvtest/clientcertpath";
+  public static final int API_SERVER_PORT = 32101;
+  CertManager certManagerMock = mock(CertManager.class);
+  KubeConfig kubeConfig = new KubeConfig(certManagerMock, null);
+
+  @Test
+    void generatesConfigYaml() {
+        when(certManagerMock.getAPIServerCertPath()).thenReturn(API_CERT_PATH);
+        when(certManagerMock.getClientCertPath()).thenReturn(CLIENT_KEY_PATH);
+        when(certManagerMock.getClientKeyPath()).thenReturn(CLIENT_CERT_PATH);
+
+        String yaml = kubeConfig.generateKubeConfigYaml(API_SERVER_PORT);
+
+        assertThat(yaml)
+                .contains(""+API_SERVER_PORT)
+                .contains(API_CERT_PATH)
+                .contains(CLIENT_CERT_PATH)
+                .contains(CLIENT_KEY_PATH);
+    }
+
+
+}

samples/src/test/java/io/javaoperatorsdk/jenvtest/KubeApiServerTest.java

@@ -2,6 +2,7 @@
 
 import org.junit.jupiter.api.Test;
 
+import io.fabric8.kubernetes.client.Config;
 import io.fabric8.kubernetes.client.KubernetesClientBuilder;
 
 import static io.javaoperatorsdk.jenvtest.TestUtils.NON_LATEST_API_SERVER_VERSION;
@@ -36,6 +37,19 @@ void usingWildcardVersion() {
     kubeApi.stop();
   }
 
+  @Test
+  void creatingClientFromConfigString() {
+    var kubeApi = new KubeAPIServer();
+    kubeApi.start();
+
+    var client =
+        new KubernetesClientBuilder().withConfig(Config.fromKubeconfig(kubeApi.getKubeConfigYaml()))
+            .build();
+    TestUtils.simpleTest(client);
+
+    kubeApi.stop();
+  }
+
   void testWithAPIServer(KubeAPIServer kubeApi) {
     kubeApi.start();
     simpleTest();