fix: allow multiple configs listed in KUBECONFIG (#779)

Signed-off-by: Andre Dietisheim <[email protected]>

src/main/java/io/fabric8/kubernetes/client/KubeConfigFile.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * 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.fabric8.kubernetes.client;
+
+import io.fabric8.kubernetes.api.model.Config;
+import io.fabric8.kubernetes.client.internal.KubeConfigUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.io.File;
+import java.io.IOException;
+
+public class KubeConfigFile {
+
+  private static final Logger LOGGER = LoggerFactory.getLogger(KubeConfigFile.class);
+
+  private final File file;
+  private boolean parsed = false;
+  private Config config;
+
+  public KubeConfigFile(String file) {
+    this(new File(file), null);
+  }
+
+  public KubeConfigFile(File file) {
+    this(file, null);
+  }
+
+  private KubeConfigFile(File file, Config config) {
+    this.file = file;
+    this.config = config;
+  }
+
+  public File getFile() {
+    return file;
+  }
+
+  public Config getConfig() {
+    if (!parsed) {
+      this.config = createConfig(file);
+      this.parsed = true;
+    }
+    return config;
+  }
+
+  private Config createConfig(File file) {
+    Config config = null;
+    try {
+      if (isReadable(file)) {
+        LOGGER.debug("Found for Kubernetes config at: [{}].", file.getPath());
+        config = KubeConfigUtils.parseConfig(file);
+      }
+    } catch (IOException e) {
+      LOGGER.debug("Kubernetes file at [{}] is not a valid config. Ignoring.", file.getPath(), e);
+    }
+    return config;
+  }
+
+  public boolean isReadable() {
+    return isReadable(file);
+  }
+
+  private boolean isReadable(File file) {
+    try {
+      return file != null
+          && file.isFile();
+    } catch (SecurityException e) {
+      return false;
+    }
+  }
+}

src/main/java/io/fabric8/kubernetes/client/internal/KubeConfigUtils.java

@@ -0,0 +1,205 @@
+/*
+ * Copyright (C) 2015 Red Hat, Inc.
+ *
+ * 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.fabric8.kubernetes.client.internal;
+
+import io.fabric8.kubernetes.api.model.AuthInfo;
+import io.fabric8.kubernetes.api.model.Cluster;
+import io.fabric8.kubernetes.api.model.Config;
+import io.fabric8.kubernetes.api.model.ConfigBuilder;
+import io.fabric8.kubernetes.api.model.Context;
+import io.fabric8.kubernetes.api.model.NamedAuthInfo;
+import io.fabric8.kubernetes.api.model.NamedCluster;
+import io.fabric8.kubernetes.api.model.NamedContext;
+import io.fabric8.kubernetes.api.model.NamedExtension;
+import io.fabric8.kubernetes.api.model.PreferencesBuilder;
+import io.fabric8.kubernetes.client.utils.Serialization;
+import io.fabric8.kubernetes.client.utils.Utils;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.List;
+
+/**
+ * Helper class for working with the YAML config file thats located in
+ * <code>~/.kube/config</code> which is updated when you use commands
+ * like <code>osc login</code> and <code>osc project myproject</code>
+ */
+public class KubeConfigUtils {
+  private KubeConfigUtils() {
+  }
+
+  public static Config parseConfig(File file) throws IOException {
+    return Serialization.unmarshal(new FileInputStream(file), Config.class);
+  }
+
+  public static Config parseConfigFromString(String contents) {
+    return Serialization.unmarshal(contents, Config.class);
+  }
+
+  /**
+   * Returns the current context in the given config
+   *
+   * @param config Config object
+   * @return returns context in config if found, otherwise null
+   */
+  public static NamedContext getCurrentContext(Config config) {
+    String contextName = config.getCurrentContext();
+    if (contextName != null) {
+      List<NamedContext> contexts = config.getContexts();
+      if (contexts != null) {
+        for (NamedContext context : contexts) {
+          if (contextName.equals(context.getName())) {
+            return context;
+          }
+        }
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Returns the current user token for the config and current context
+   *
+   * @param config Config object
+   * @param context Context object
+   * @return returns current user based upon provided parameters.
+   */
+  public static String getUserToken(Config config, Context context) {
+    AuthInfo authInfo = getUserAuthInfo(config, context);
+    if (authInfo != null) {
+      return authInfo.getToken();
+    }
+    return null;
+  }
+
+  /**
+   * Returns the current {@link AuthInfo} for the current context and user
+   *
+   * @param config Config object
+   * @param context Context object
+   * @return {@link AuthInfo} for current context
+   */
+  public static AuthInfo getUserAuthInfo(Config config, Context context) {
+    AuthInfo authInfo = null;
+    if (config != null && context != null) {
+      String user = context.getUser();
+      if (user != null) {
+        List<NamedAuthInfo> users = config.getUsers();
+        if (users != null) {
+          authInfo = users.stream()
+              .filter(u -> u.getName().equals(user))
+              .findAny()
+              .map(NamedAuthInfo::getUser)
+              .orElse(null);
+        }
+      }
+    }
+    return authInfo;
+  }
+
+  /**
+   * Returns the current {@link Cluster} for the current context
+   *
+   * @param config {@link Config} config object
+   * @param context {@link Context} context object
+   * @return current {@link Cluster} for current context
+   */
+  public static Cluster getCluster(Config config, Context context) {
+    Cluster cluster = null;
+    if (config != null && context != null) {
+      String clusterName = context.getCluster();
+      if (clusterName != null) {
+        List<NamedCluster> clusters = config.getClusters();
+        if (clusters != null) {
+          cluster = clusters.stream()
+              .filter(c -> c.getName().equals(clusterName))
+              .findAny()
+              .map(NamedCluster::getCluster)
+              .orElse(null);
+        }
+      }
+    }
+    return cluster;
+  }
+
+  /**
+   * Get User index from Config object
+   *
+   * @param config {@link io.fabric8.kubernetes.api.model.Config} Kube Config
+   * @param userName username inside Config
+   * @return index of user in users array
+   */
+  public static int getNamedUserIndexFromConfig(Config config, String userName) {
+    for (int i = 0; i < config.getUsers().size(); i++) {
+      if (config.getUsers().get(i).getName().equals(userName)) {
+        return i;
+      }
+    }
+    return -1;
+  }
+
+  /**
+   * Modify KUBECONFIG file
+   *
+   * @param kubeConfig modified {@link io.fabric8.kubernetes.api.model.Config} object
+   * @param kubeConfigPath path to KUBECONFIG
+   * @throws IOException in case of failure while writing to file
+   */
+  public static void persistKubeConfigIntoFile(Config kubeConfig, String kubeConfigPath) throws IOException {
+    try (FileWriter writer = new FileWriter(kubeConfigPath)) {
+      writer.write(Serialization.asYaml(kubeConfig));
+    }
+  }
+
+  public static Config merge(Config thisConfig, Config thatConfig) {
+    if (thisConfig == null) {
+      return thatConfig;
+    }
+    ConfigBuilder builder = new ConfigBuilder(thatConfig);
+    if (thisConfig.getClusters() != null) {
+      builder.addAllToClusters(thisConfig.getClusters());
+    }
+    if (thisConfig.getContexts() != null) {
+      builder.addAllToContexts(thisConfig.getContexts());
+    }
+    if (thisConfig.getUsers() != null) {
+      builder.addAllToUsers(thisConfig.getUsers());
+    }
+    if (thisConfig.getExtensions() != null) {
+      builder.addAllToExtensions(thisConfig.getExtensions());
+    }
+    if (!builder.hasCurrentContext()
+        && Utils.isNotNullOrEmpty(thisConfig.getCurrentContext())) {
+      builder.withCurrentContext(thisConfig.getCurrentContext());
+    }
+    Config merged = builder.build();
+    mergePreferences(thisConfig, merged);
+    return merged;
+  }
+
+  public static void mergePreferences(io.fabric8.kubernetes.api.model.Config source,
+      io.fabric8.kubernetes.api.model.Config destination) {
+    if (source.getPreferences() != null) {
+      PreferencesBuilder builder = new PreferencesBuilder(destination.getPreferences());
+      if (source.getPreferences() != null) {
+        builder.addToExtensions(source.getExtensions().toArray(new NamedExtension[] {}));
+      }
+      destination.setPreferences(builder.build());
+    }
+  }
+}