Merge pull request #313 from brendandburns/env

Add config file persistence.

Author: brendandburns

util/src/main/java/io/kubernetes/client/util/ClientBuilder.java

@@ -25,7 +25,6 @@
 import io.kubernetes.client.util.credentials.KubeconfigAuthentication;
 import java.io.ByteArrayInputStream;
 import java.io.File;
-import java.io.FileNotFoundException;
 import java.io.FileReader;
 import java.io.IOException;
 import java.io.Reader;
@@ -71,13 +70,29 @@ public static ApiClient defaultClient() throws IOException {
    *     cannot be read.
    */
   public static ClientBuilder standard() throws IOException {
-    final FileReader kubeConfigReader = findConfigFromEnv();
-    if (kubeConfigReader != null) {
-      return kubeconfig(loadKubeConfig(kubeConfigReader));
+    return standard(true);
+  }
+
+  public static ClientBuilder standard(boolean persistConfig) throws IOException {
+    final File kubeConfig = findConfigFromEnv();
+    if (kubeConfig != null) {
+      try (FileReader kubeConfigReader = new FileReader(kubeConfig)) {
+        KubeConfig kc = loadKubeConfig(kubeConfigReader);
+        if (persistConfig) {
+          kc.setPersistConfig(new FilePersister(kubeConfig));
+        }
+        return kubeconfig(kc);
+      }
     }
-    final FileReader configReader = findConfigInHomeDir();
-    if (configReader != null) {
-      return kubeconfig(loadKubeConfig(configReader));
+    final File config = findConfigInHomeDir();
+    if (config != null) {
+      try (FileReader configReader = new FileReader(config)) {
+        KubeConfig kc = loadKubeConfig(configReader);
+        if (persistConfig) {
+          kc.setPersistConfig(new FilePersister(config));
+        }
+        return kubeconfig(kc);
+      }
     }
     final File clusterCa = new File(SERVICEACCOUNT_CA_PATH);
     if (clusterCa.exists()) {
@@ -86,24 +101,24 @@ public static ClientBuilder standard() throws IOException {
     return new ClientBuilder();
   }
 
-  private static FileReader findConfigFromEnv() throws FileNotFoundException {
+  private static File findConfigFromEnv() {
     String kubeConfigPath = System.getenv(ENV_KUBECONFIG);
     if (kubeConfigPath == null) {
       return null;
     }
     final File kubeConfig = new File(kubeConfigPath);
     if (kubeConfig.exists()) {
-      return new FileReader(kubeConfig);
+      return kubeConfig;
     } else {
       log.debug("Could not find file specified in $KUBECONFIG");
       return null;
     }
   }
 
-  private static FileReader findConfigInHomeDir() throws FileNotFoundException {
+  private static File findConfigInHomeDir() {
     final File config = new File(new File(System.getenv(ENV_HOME), KUBEDIR), KUBECONFIG);
     if (config.exists()) {
-      return new FileReader(config);
+      return config;
     } else {
       log.debug("Could not find ~/.kube/config");
       return null;

util/src/main/java/io/kubernetes/client/util/ConfigPersister.java

@@ -0,0 +1,26 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package io.kubernetes.client.util;
+
+import java.io.IOException;
+import java.util.ArrayList;
+
+public interface ConfigPersister {
+  public void save(
+      ArrayList<Object> contexts,
+      ArrayList<Object> clusters,
+      ArrayList<Object> users,
+      Object preferences,
+      String currentContext)
+      throws IOException;
+}

util/src/main/java/io/kubernetes/client/util/FilePersister.java

@@ -0,0 +1,59 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package io.kubernetes.client.util;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import org.yaml.snakeyaml.Yaml;
+
+public class FilePersister implements ConfigPersister {
+  File configFile;
+
+  public FilePersister(String filename) {
+    this(new File(filename));
+  }
+
+  public FilePersister(File file) {
+    this.configFile = file;
+  }
+
+  public void save(
+      ArrayList<Object> contexts,
+      ArrayList<Object> clusters,
+      ArrayList<Object> users,
+      Object preferences,
+      String currentContext)
+      throws IOException {
+    HashMap<String, Object> config = new HashMap<>();
+    config.put("apiVersion", "v1");
+    config.put("kind", "Config");
+    config.put("current-context", currentContext);
+    config.put("preferences", preferences);
+
+    config.put("clusters", clusters);
+    config.put("contexts", contexts);
+    config.put("users", users);
+
+    // Note this is imperfect, should protect against other processes writing this file too...
+    synchronized (configFile) {
+      try (FileWriter fw = new FileWriter(configFile)) {
+        Yaml yaml = new Yaml();
+        yaml.dump(config, fw);
+        fw.flush();
+      }
+    }
+  }
+}

util/src/main/java/io/kubernetes/client/util/KubeConfig.java

@@ -15,9 +15,6 @@
 import io.kubernetes.client.util.authenticators.Authenticator;
 import io.kubernetes.client.util.authenticators.AzureActiveDirectoryAuthenticator;
 import io.kubernetes.client.util.authenticators.GCPAuthenticator;
-import java.io.File;
-import java.io.FileNotFoundException;
-import java.io.FileReader;
 import java.io.IOException;
 import java.io.Reader;
 import java.nio.file.FileSystems;
@@ -49,10 +46,13 @@ public class KubeConfig {
   private ArrayList<Object> clusters;
   private ArrayList<Object> contexts;
   private ArrayList<Object> users;
+  String currentContextName;
   Map<String, Object> currentContext;
   Map<String, Object> currentCluster;
   Map<String, Object> currentUser;
   String currentNamespace;
+  Object preferences;
+  ConfigPersister persister;
 
   public static void registerAuthenticator(Authenticator auth) {
     synchronized (authenticators) {
@@ -65,15 +65,6 @@ public static void registerAuthenticator(Authenticator auth) {
     registerAuthenticator(new AzureActiveDirectoryAuthenticator());
   }
 
-  /** Load a Kubernetes config from the default location */
-  public static KubeConfig loadDefaultKubeConfig() throws FileNotFoundException {
-    File config = new File(new File(System.getenv(ENV_HOME), KUBEDIR), KUBECONFIG);
-    if (!config.exists()) {
-      return null;
-    }
-    return loadKubeConfig(new FileReader(config));
-  }
-
   /** Load a Kubernetes config from a Reader */
   public static KubeConfig loadKubeConfig(Reader input) {
     Yaml yaml = new Yaml(new SafeConstructor());
@@ -84,9 +75,11 @@ public static KubeConfig loadKubeConfig(Reader input) {
     ArrayList<Object> contexts = (ArrayList<Object>) configMap.get("contexts");
     ArrayList<Object> clusters = (ArrayList<Object>) configMap.get("clusters");
     ArrayList<Object> users = (ArrayList<Object>) configMap.get("users");
+    Object preferences = configMap.get("preferences");
 
     KubeConfig kubeConfig = new KubeConfig(contexts, clusters, users);
     kubeConfig.setContext(currentContext);
+    kubeConfig.setPreferences(preferences);
 
     return kubeConfig;
   }
@@ -98,11 +91,15 @@ public KubeConfig(
     this.users = users;
   }
 
+  public String getCurrentContext() {
+    return currentContextName;
+  }
+
   public boolean setContext(String context) {
     if (context == null) {
       return false;
     }
-
+    currentContextName = context;
     currentCluster = null;
     currentUser = null;
     Map<String, Object> ctx = findObject(contexts, context);
@@ -131,10 +128,26 @@ public boolean setContext(String context) {
     return true;
   }
 
+  public ArrayList<Object> getContexts() {
+    return contexts;
+  }
+
+  public ArrayList<Object> getClusters() {
+    return clusters;
+  }
+
+  public ArrayList<Object> getUsers() {
+    return users;
+  }
+
   public String getNamespace() {
     return currentNamespace;
   }
 
+  public Object getPreferences() {
+    return preferences;
+  }
+
   public String getServer() {
     return getData(currentCluster, "server");
   }
@@ -186,7 +199,13 @@ public String getAccessToken() {
         if (auth != null) {
           if (auth.isExpired(authConfig)) {
             authConfig = auth.refresh(authConfig);
-            // TODO persist things here.
+            if (persister != null) {
+              try {
+                persister.save(contexts, clusters, users, preferences, currentContextName);
+              } catch (IOException ex) {
+                log.error("Failed to persist new token", ex);
+              }
+            }
           }
           return auth.getToken(authConfig);
         } else {
@@ -219,6 +238,19 @@ public boolean verifySSL() {
     return true;
   }
 
+  /**
+   * Set persistence for this config.
+   *
+   * @param persister The persistence to use, or null to not persist the config.
+   */
+  public void setPersistConfig(ConfigPersister persister) {
+    this.persister = persister;
+  }
+
+  public void setPreferences(Object preferences) {
+    this.preferences = preferences;
+  }
+
   private static String getData(Map<String, Object> obj, String key) {
     if (obj == null) {
       return null;

util/src/test/java/io/kubernetes/client/ExecTest.java

@@ -37,7 +37,7 @@ public class ExecTest {
 
   @Before
   public void setup() throws IOException {
-    client = ClientBuilder.defaultClient();
+    client = new ClientBuilder().setBasePath("http://localhost:9999").build();
   }
 
   @Test

util/src/test/java/io/kubernetes/client/util/FilePersisterTest.java

@@ -0,0 +1,53 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package io.kubernetes.client.util;
+
+import static org.junit.Assert.*;
+
+import com.google.common.io.Resources;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+/** Tests for the FilePersister helper class */
+public class FilePersisterTest {
+
+  private static final String KUBECONFIG_FILE_PATH = Resources.getResource("kubeconfig").getPath();
+
+  @Rule public TemporaryFolder folder = new TemporaryFolder();
+
+  @Test
+  public void testPersistence() throws IOException {
+    File file = folder.newFile("testconfig");
+    FilePersister fp = new FilePersister(file);
+
+    KubeConfig config = KubeConfig.loadKubeConfig(new FileReader(KUBECONFIG_FILE_PATH));
+
+    fp.save(
+        config.getContexts(),
+        config.getClusters(),
+        config.getUsers(),
+        config.getPreferences(),
+        config.getCurrentContext());
+
+    KubeConfig configOut = KubeConfig.loadKubeConfig(new FileReader(file));
+
+    assertEquals(config.getCurrentContext(), configOut.getCurrentContext());
+    assertEquals(config.getClusters(), configOut.getClusters());
+    assertEquals(config.getContexts(), configOut.getContexts());
+    assertEquals(config.getUsers(), configOut.getUsers());
+  }
+}

util/src/test/resources/kubeconfig-http

@@ -1,4 +1,5 @@
 apiVersion: v1
+kind: Config
 clusters:
   - cluster:
       server: localhost
@@ -8,4 +9,10 @@ contexts:
   - context:
       cluster: foo
     name: foo-context
+users:
+  - user:
+      client-certificate: /some/fake/path/client.crt
+      client-key: /some/other/fake/path/client.key
+    name: fake-user
+preferences: {}
 current-context: foo-context