fix(plugins): allow plugins to act as auth providers

agent-api/src/main/java/com/intergral/deep/agent/api/DeepRuntimeException.java

@@ -0,0 +1,29 @@
+/*
+ *     Copyright (C) 2023  Intergral GmbH
+ *
+ *     This program is free software: you can redistribute it and/or modify
+ *     it under the terms of the GNU Affero General Public License as published by
+ *     the Free Software Foundation, either version 3 of the License, or
+ *     (at your option) any later version.
+ *
+ *     This program is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU Affero General Public License for more details.
+ *
+ *     You should have received a copy of the GNU Affero General Public License
+ *     along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.intergral.deep.agent.api;
+
+public class DeepRuntimeException extends RuntimeException {
+
+  public DeepRuntimeException(final String message) {
+    super(message);
+  }
+
+  public DeepRuntimeException(final String message, final Throwable cause) {
+    super(message, cause);
+  }
+}

agent-api/src/main/java/com/intergral/deep/agent/api/IDeep.java

@@ -30,6 +30,25 @@
  */
 public interface IDeep {
 
+  /**
+   * Get the current state of deep.
+   *
+   * @return {@code true} if deep is currently enabled and sending requests, else {@code false}
+   */
+  boolean isEnabled();
+
+
+  /**
+   * This method can be used to disabled or enable Deep.
+   * <p>
+   * Changing the state to {@code false} (ie disabled) will cause deep to uninstall all the tracepoints and clear the current config.
+   * Meaning that when deep is enabled again it will have to reinstall the configuration. It is therefore advised to not call this function
+   * too frequently.
+   *
+   * @param enabled the new state to become
+   */
+  void setEnabled(final boolean enabled);
+
   /**
    * Get the version of deep being used.
    *

agent-api/src/main/java/com/intergral/deep/agent/api/IRegistration.java

@@ -20,10 +20,17 @@
 /**
  * This is a generic interface from the result of a registration.
  */
-public interface IRegistration {
+public interface IRegistration<T> {
 
   /**
    * Unregister the item registered.
    */
   void unregister();
+
+  /**
+   * Get the registered item
+   *
+   * @return the item that this registration is for.
+   */
+  T get();
 }

agent-api/src/main/java/com/intergral/deep/agent/api/auth/AuthProvider.java

@@ -17,6 +17,8 @@
 
 package com.intergral.deep.agent.api.auth;
 
+import com.intergral.deep.agent.api.DeepRuntimeException;
+import com.intergral.deep.agent.api.plugin.IPlugin;
 import com.intergral.deep.agent.api.settings.ISettings;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.InvocationTargetException;
@@ -32,6 +34,18 @@ public static IAuthProvider provider(final ISettings settings) {
     if (serviceAuthProvider == null || serviceAuthProvider.trim().isEmpty()) {
       return NOOP_PROVIDER;
     }
+
+    // check if we have a plugin of this name that we can use
+    final IPlugin plugin = settings.getPlugin(serviceAuthProvider);
+    if (plugin != null) {
+      if (plugin instanceof IAuthProvider) {
+        return (IAuthProvider) plugin;
+      } else {
+        throw new DeepRuntimeException(
+            String.format("Cannot use plugin %s as auth provider, must implement IAuthProvider interface.", plugin.name()));
+      }
+    }
+
     try {
       final Class<?> aClass = Class.forName(serviceAuthProvider);
       final Constructor<?> constructor = aClass.getConstructor(ISettings.class);
@@ -42,7 +56,7 @@ public static IAuthProvider provider(final ISettings settings) {
              | InvocationTargetException
              | InstantiationException
              | IllegalAccessException e) {
-      throw new RuntimeException(e);
+      throw new RuntimeException(String.format("Cannot load auth provider %s", serviceAuthProvider), e);
     }
   }
 

agent-api/src/main/java/com/intergral/deep/agent/api/plugin/IPlugin.java

@@ -70,7 +70,14 @@ default boolean isActive(final ISettings settings) {
   /**
    * This type describes a registered plugin.
    */
-  interface IPluginRegistration extends IRegistration {
+  interface IPluginRegistration extends IRegistration<IPlugin> {
 
+    /**
+     * Indicates if this plugin is currently set to be the auth provider
+     *
+     * @return {@code true} if the registered plugin is an {@link com.intergral.deep.agent.api.auth.IAuthProvider} and deep is configured to
+     * use this provider, else {@code false}
+     */
+    boolean isAuthProvider();
   }
 }

agent-api/src/main/java/com/intergral/deep/agent/api/resource/ConfigurationException.java

@@ -12,13 +12,18 @@ public final class ConfigurationException extends RuntimeException {
 
   /**
    * Create a new configuration exception with specified {@code message} and without a cause.
+   *
+   * @param message The exception message
    */
   public ConfigurationException(String message) {
     super(message);
   }
 
   /**
    * Create a new configuration exception with specified {@code message} and {@code cause}.
+   *
+   * @param message The exception message
+   * @param cause The root cause of this exception
    */
   public ConfigurationException(String message, Throwable cause) {
     super(message, cause);

agent-api/src/main/java/com/intergral/deep/agent/api/settings/ISettings.java

@@ -17,14 +17,43 @@
 
 package com.intergral.deep.agent.api.settings;
 
+import com.intergral.deep.agent.api.plugin.IPlugin;
 import com.intergral.deep.agent.api.resource.Resource;
 import java.util.Map;
 
 public interface ISettings {
 
+  /**
+   * This is the settings key for the configured auth provider
+   */
+  String KEY_AUTH_PROVIDER = "service.auth.provider";
+
+  /**
+   * This is the setting key for enabling or disabling deep.
+   */
+  String KEY_ENABLED = "enabled";
+
+  /**
+   * This is the setting key for the service url
+   */
+  String KEY_SERVICE_URL = "service.url";
+
   <T> T getSettingAs(String key, Class<T> clazz);
 
   Map<String, String> getMap(String attributeProperty);
 
+  /**
+   * Returns the resource that describes this client
+   *
+   * @return the {@link Resource}
+   */
   Resource getResource();
+
+  /**
+   * Look for a plugin with the given name or class name.
+   *
+   * @param name the plugin name or the plugin class name
+   * @return the {@link IPlugin} or {@code null}
+   */
+  IPlugin getPlugin(final String name);
 }

agent-api/src/main/java/com/intergral/deep/agent/api/spi/Ordered.java

@@ -16,6 +16,8 @@ public interface Ordered {
    * Returns the order of applying the SPI implementing this interface. Higher values are applied
    * later, for example: an SPI with order=1 will run after an SPI with order=0. SPI implementations
    * with equal values will be run in a non-deterministic order.
+   *
+   * @return the order value
    */
   default int order() {
     return 0;

agent-api/src/main/java/com/intergral/deep/agent/api/tracepoint/ITracepoint.java

@@ -41,7 +41,7 @@ default String id() {
     return UUID.randomUUID().toString();
   }
 
-  interface ITracepointRegistration extends IRegistration {
+  interface ITracepointRegistration extends IRegistration<ITracepoint> {
 
   }
 }

agent/src/main/java/com/intergral/deep/agent/DeepAgent.java

@@ -19,9 +19,12 @@
 
 import com.intergral.deep.agent.api.DeepVersion;
 import com.intergral.deep.agent.api.IDeep;
+import com.intergral.deep.agent.api.auth.IAuthProvider;
 import com.intergral.deep.agent.api.plugin.IPlugin;
 import com.intergral.deep.agent.api.plugin.IPlugin.IPluginRegistration;
 import com.intergral.deep.agent.api.resource.Resource;
+import com.intergral.deep.agent.api.settings.ISettings;
+import com.intergral.deep.agent.api.tracepoint.ITracepoint;
 import com.intergral.deep.agent.api.tracepoint.ITracepoint.ITracepointRegistration;
 import com.intergral.deep.agent.grpc.GrpcService;
 import com.intergral.deep.agent.plugins.PluginLoader;
@@ -74,7 +77,29 @@ public String getVersion() {
 
   public IPluginRegistration registerPlugin(final IPlugin plugin) {
     this.settings.addPlugin(plugin);
-    return () -> this.settings.removePlugin(plugin);
+    final boolean isAuthProvider;
+    if (plugin instanceof IAuthProvider) {
+      final String settingAs = this.settings.getSettingAs(ISettings.KEY_AUTH_PROVIDER, String.class);
+      isAuthProvider = settingAs != null && settingAs.equals(plugin.getClass().getName());
+    } else {
+      isAuthProvider = false;
+    }
+    return new IPluginRegistration() {
+      @Override
+      public boolean isAuthProvider() {
+        return isAuthProvider;
+      }
+
+      @Override
+      public void unregister() {
+        settings.removePlugin(plugin);
+      }
+
+      @Override
+      public IPlugin get() {
+        return plugin;
+      }
+    };
   }
 
   @Override
@@ -86,6 +111,62 @@ public ITracepointRegistration registerTracepoint(final String path, final int l
   public ITracepointRegistration registerTracepoint(final String path, final int line, final Map<String, String> args,
       final Collection<String> watches) {
     final TracePointConfig tracePointConfig = this.tracepointConfig.addCustom(path, line, args, watches);
-    return () -> this.tracepointConfig.removeCustom(tracePointConfig);
+    return new ITracepointRegistration() {
+      @Override
+      public void unregister() {
+        tracepointConfig.removeCustom(tracePointConfig);
+      }
+
+      @Override
+      public ITracepoint get() {
+        return new ITracepoint() {
+          @Override
+          public String path() {
+            return path;
+          }
+
+          @Override
+          public int line() {
+            return line;
+          }
+
+          @Override
+          public Map<String, String> args() {
+            return args;
+          }
+
+          @Override
+          public Collection<String> watches() {
+            return watches;
+          }
+
+          @Override
+          public String id() {
+            return tracePointConfig.getId();
+          }
+        };
+      }
+    };
+  }
+
+  @Override
+  public boolean isEnabled() {
+    return this.settings.getSettingAs(ISettings.KEY_ENABLED, Boolean.class);
+  }
+
+  @Override
+  public synchronized void setEnabled(final boolean enabled) {
+    // we are already the desired state - so do nothing
+    if (isEnabled() == enabled) {
+      return;
+    }
+
+    // update config to new state
+    this.settings.setActive(enabled);
+
+    // if we are disabling then we need to clear configs
+    if (!enabled) {
+      this.tracepointConfig.configUpdate(0, null, Collections.emptyList());
+    }
   }
 }

agent/src/main/java/com/intergral/deep/agent/poll/LongPollService.java

@@ -56,6 +56,11 @@ public void start(final ITracepointConfig tracepointConfig) {
 
   @Override
   public void run(long now) {
+    if (!this.settings.isActive()) {
+      // we have been disabled so skip this poll
+      // we will pause like normal and try again later
+      return;
+    }
     final PollConfigGrpc.PollConfigBlockingStub blockingStub = this.grpcService.pollService();
 
     final PollRequest.Builder builder = PollRequest.newBuilder();
@@ -69,7 +74,10 @@ public void run(long now) {
         .build();
 
     final PollResponse response = blockingStub.poll(pollRequest);
-
+    // check we are still active
+    if (!this.settings.isActive()) {
+      return;
+    }
     if (response.getResponseType() == ResponseType.NO_CHANGE) {
       this.tracepointConfig.noChange(response.getTsNanos());
     } else {