Merge pull request #6512 from Icinga/feature/sni-environment

Refactor environment for API connections

doc/06-distributed-monitoring.md

@@ -116,8 +116,8 @@ you still need a [Host](09-object-types.md#objecttype-host) object.
 
 In case you are using the CLI commands later, you don't have to write
 this configuration from scratch in a text editor.
-The [ApiListener](09-object-types.md#objecttype-apilistener)
-object is used to load the SSL certificates and specify restrictions, e.g.
+The [ApiListener](09-object-types.md#objecttype-apilistener) object is
+used to load the TLS certificates and specify restrictions, e.g.
 for accepting configuration commands.
 
 It is also used for the [Icinga 2 REST API](12-icinga2-api.md#icinga2-api) which shares
@@ -2793,3 +2793,36 @@ Add the global zone `global-templates` in case it did not exist.
       global = true
     }
     EOF
+
+## Using Multiple Environments <a id="distributed-monitoring-environments"></a>
+
+In some cases it can be desired to run multiple Icinga instances on the same host.
+Two potential scenarios include:
+
+* Different versions of the same monitoring configuration (e.g. production and testing)
+* Disparate sets of checks for entirely unrelated monitoring environments (e.g. infrastructure and applications)
+
+The configuration is done with the global constants `ApiBindHost` and `ApiBindPort`
+or the `bind_host` and `bind_port` attributes of the
+[ApiListener](09-object-types.md#objecttype-apilistener) object.
+
+The environment must be set with the global constant `Environment` or as object attribute
+of the [IcingaApplication](#objecttype-icingaapplication) object.
+
+In any case the constant is default value for the attribute and the direct configuration in the objects
+have more precedence. The constants have been added to allow the values being set from the CLI on startup.
+
+When Icinga establishes a TLS connection to another cluster instance it automatically uses the [SNI extension](https://en.wikipedia.org/wiki/Server_Name_Indication)
+to signal which endpoint it is attempting to connect to. On its own this can already be used to position multiple
+Icinga instances behind a load balancer.
+
+SNI example: `icinga2-client1.localdomain`
+
+However, if the environment is configured to `production`, Icinga appends the environment name to the SNI hostname like this:
+
+SNI example with environment: `icinga2-client1.localdomain:production`
+
+Middleware like loadbalancers or TLS proxies can read the SNI header and route the connection to the appropriate target.
+I.e., it uses a single externally-visible TCP port (usually 5665) and forwards connections to one or more Icinga
+instances which are bound to a local TCP port. It does so by inspecting the environment name that is sent as part of the
+SNI extension.

doc/09-object-types.md

@@ -67,6 +67,7 @@ Configuration Attributes:
   access\_control\_allow\_credentials   | Boolean               | **Deprecated.** Indicates whether or not the actual request can be made using credentials. Defaults to `true`. [(MDN docs)](https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS#Access-Control-Allow-Credentials)
   access\_control\_allow\_headers       | String                | **Deprecated.** Used in response to a preflight request to indicate which HTTP headers can be used when making the actual request. Defaults to `Authorization`. [(MDN docs)](https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS#Access-Control-Allow-Headers)
   access\_control\_allow\_methods       | String                | **Deprecated.** Used in response to a preflight request to indicate which HTTP methods can be used when making the actual request. Defaults to `GET, POST, PUT, DELETE`. [(MDN docs)](https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS#Access-Control-Allow-Methods)
+  environment                           | String                | **Optional.** Used as suffix in TLS SNI extension name; default from constant `ApiEnvironment`, which is empty.
 
 The attributes `access_control_allow_credentials`, `access_control_allow_headers` and `access_control_allow_methods`
 are controlled by Icinga 2 and are not changeable by config any more.
@@ -816,6 +817,7 @@ Configuration Attributes:
   enable\_service\_checks   | Boolean               | **Optional.** Whether active service checks are globally enabled. Defaults to true.
   enable\_perfdata          | Boolean               | **Optional.** Whether performance data processing is globally enabled. Defaults to true.
   vars                      | Dictionary            | **Optional.** A dictionary containing custom attributes that are available globally.
+  environment               | String                | **Optional.** Specify the Icinga environment. This overrides the `Environment` constant specified in the configuration or on the CLI with `--define`. Defaults to empty.
 
 ## IdoMySqlConnection <a id="objecttype-idomysqlconnection"></a>
 

doc/16-upgrading-icinga-2.md

@@ -41,6 +41,7 @@ has been removed and this setting has no effect.
 
 New [Icinga constants](17-language-reference.md#icinga-constants) have been added in this release.
 
+* `Environment` for specifying the Icinga environment. Defaults to not set.
 * `ApiBindHost` and `ApiBindPort` to allow overriding the default ApiListener values. This will be used for an Icinga addon only.
 
 ## Upgrading to v2.9 <a id="upgrading-to-2-9"></a>

doc/17-language-reference.md

@@ -407,10 +407,10 @@ Constant            | Description
 --------------------|-------------------
 Vars                |**Read-write.** Contains a dictionary with global custom attributes. Not set by default.
 NodeName            |**Read-write.** Contains the cluster node name. Set to the local hostname by default.
+Environment         |**Read-write.** The name of the Icinga environment. Included in the SNI host name for outbound connections. Not set by default.
 RunAsUser           |**Read-write.** Defines the user the Icinga 2 daemon is running as. Set in the Icinga 2 sysconfig.
 RunAsGroup          |**Read-write.** Defines the group the Icinga 2 daemon is running as. Set in the Icinga 2 sysconfig.
 MaxConcurrentChecks |**Read-write.** The number of max checks run simultaneously. Defaults to `512`.
-Environment         |**Read-write.** The name of the Icinga environment. Included in the SNI host name when making outbound connections. Defaults to `production`.
 ApiBindHost         |**Read-write.** Overrides the default value for the ApiListener `bind_host` attribute. Not set by default.
 ApiBindPort         |**Read-write.** Overrides the default value for the ApiListener `bind_port` attribute. Not set by default.
 
@@ -454,7 +454,6 @@ SysconfDir          |**Read-only.** Contains the path of the sysconf directory.
 LocalStateDir       |**Read-only.** Contains the path of the local state directory. Defaults to `PrefixDir + "/var"`.
 RunDir              |**Read-only.** Contains the path of the run directory. Defaults to `LocalStateDir + "/run"`.
 
-
 Advanced runtime constants. Please only use them if advised by support or developers.
 
 Variable                   | Description

icinga-app/icinga.cpp

@@ -297,8 +297,6 @@ static int Main()
 	Application::DeclareConst("Concurrency", std::thread::hardware_concurrency());
 	Application::DeclareConst("MaxConcurrentChecks", Application::GetDefaultMaxConcurrentChecks());
 
-	ScriptGlobal::Set("Environment", "production");
-
 	ScriptGlobal::Set("AttachDebugger", false);
 
 	ScriptGlobal::Set("PlatformKernel", Utility::GetPlatformKernel());

lib/base/CMakeLists.txt

@@ -27,7 +27,7 @@ mkclass_target(sysloglogger.ti sysloglogger-ti.cpp sysloglogger-ti.hpp)
 
 set(base_SOURCES
   i2-base.hpp
-  application.cpp application.hpp application-ti.hpp application-version.cpp
+  application.cpp application.hpp application-ti.hpp application-version.cpp application-environment.cpp
   array.cpp array.hpp array-script.cpp
   base64.cpp base64.hpp
   boolean.cpp boolean.hpp boolean-script.cpp

lib/base/application-environment.cpp

@@ -0,0 +1,34 @@
+/******************************************************************************
+ * Icinga 2                                                                   *
+ * Copyright (C) 2012-2018 Icinga Development Team (https://www.icinga.com/)  *
+ *                                                                            *
+ * This program is free software; you can redistribute it and/or              *
+ * modify it under the terms of the GNU General Public License                *
+ * as published by the Free Software Foundation; either version 2             *
+ * 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 General Public License for more details.                               *
+ *                                                                            *
+ * You should have received a copy of the GNU General Public License          *
+ * along with this program; if not, write to the Free Software Foundation     *
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.             *
+ ******************************************************************************/
+
+#include "base/application.hpp"
+#include "base/scriptglobal.hpp"
+
+using namespace icinga;
+
+String Application::GetAppEnvironment()
+{
+	Value defaultValue = Empty;
+	return ScriptGlobal::Get("Environment", &defaultValue);
+}
+
+void Application::SetAppEnvironment(const String& name)
+{
+	ScriptGlobal::Set("Environment", name);
+}

lib/base/application.hpp

@@ -107,6 +107,9 @@ public:
 	static String GetAppVersion();
 	static String GetAppSpecVersion();
 
+	static String GetAppEnvironment();
+	static void SetAppEnvironment(const String& name);
+
 	static double GetStartTime();
 	static void SetStartTime(double ts);
 

lib/icinga/icingaapplication.cpp

@@ -79,10 +79,10 @@ void IcingaApplication::StatsFunc(const Dictionary::Ptr& status, const Array::Pt
 			{ "enable_host_checks", icingaapplication->GetEnableHostChecks() },
 			{ "enable_service_checks", icingaapplication->GetEnableServiceChecks() },
 			{ "enable_perfdata", icingaapplication->GetEnablePerfdata() },
+			{ "environment", icingaapplication->GetEnvironment() },
 			{ "pid", Utility::GetPid() },
 			{ "program_start", Application::GetStartTime() },
-			{ "version", Application::GetAppVersion() },
-			{ "environment", ScriptGlobal::Get("Environment", &Empty) }
+			{ "version", Application::GetAppVersion() }
 		}));
 	}
 
@@ -294,6 +294,16 @@ String IcingaApplication::GetNodeName() const
 	return ScriptGlobal::Get("NodeName");
 }
 
+String IcingaApplication::GetEnvironment() const
+{
+	return Application::GetAppEnvironment();
+}
+
+void IcingaApplication::SetEnvironment(const String& value, bool suppress_events, const Value& cookie)
+{
+	Application::SetAppEnvironment(value);
+}
+
 void IcingaApplication::ValidateVars(const Lazy<Dictionary::Ptr>& lvalue, const ValidationUtils& utils)
 {
 	MacroProcessor::ValidateCustomVars(this, lvalue());

lib/icinga/icingaapplication.hpp

@@ -50,6 +50,9 @@ public:
 
 	String GetNodeName() const;
 
+	String GetEnvironment() const override;
+	void SetEnvironment(const String& value, bool suppress_events = false, const Value& cookie = Empty) override;
+
 	void ValidateVars(const Lazy<Dictionary::Ptr>& lvalue, const ValidationUtils& utils) override;
 
 private:

lib/icinga/icingaapplication.ti

@@ -26,6 +26,12 @@ namespace icinga
 
 class IcingaApplication : Application
 {
+	[config, no_storage, virtual] String environment {
+		get;
+		set;
+		default {{{ return Application::GetAppEnvironment(); }}}
+	};
+
 	[config] bool enable_notifications {
 		default {{{ return true; }}}
 	};

lib/remote/apilistener.cpp

@@ -388,16 +388,10 @@ void ApiListener::AddConnection(const Endpoint::Ptr& endpoint)
 
 	TcpSocket::Ptr client = new TcpSocket();
 
-	String serverName = endpoint->GetName();
-
-	String env = ScriptGlobal::Get("Environment", &Empty);
-	if (env != "" && env != "production")
-		serverName += ":" + env;
-
 	try {
 		endpoint->SetConnecting(true);
 		client->Connect(host, port);
-		NewClientHandler(client, serverName, RoleClient);
+		NewClientHandler(client, endpoint->GetName(), RoleClient);
 		endpoint->SetConnecting(false);
 	} catch (const std::exception& ex) {
 		endpoint->SetConnecting(false);
@@ -447,10 +441,17 @@ void ApiListener::NewClientHandlerInternal(const Socket::Ptr& client, const Stri
 
 	TlsStream::Ptr tlsStream;
 
+	String environmentName = Application::GetAppEnvironment();
+
+	String serverName = hostname;
+
+	if (!environmentName.IsEmpty())
+		serverName += ":" + environmentName;
+
 	{
 		ObjectLock olock(this);
 		try {
-			tlsStream = new TlsStream(client, hostname, role, m_SSLContext);
+			tlsStream = new TlsStream(client, serverName, role, m_SSLContext);
 		} catch (const std::exception&) {
 			Log(LogCritical, "ApiListener")
 				<< "Cannot create TLS stream from client connection (" << conninfo << ")";

tools/mkclass/classcompiler.cpp

@@ -568,7 +568,8 @@ void ClassCompiler::HandleClass(const Klass& klass, const ClassDebugInfo&)
 		<< "{" << std::endl;
 
 	for (const Field& field : klass.Fields) {
-		m_Impl << "\t" << "Set" << field.GetFriendlyName() << "(" << "GetDefault" << field.GetFriendlyName() << "(), true);" << std::endl;
+		if (!field.PureSetAccessor)
+			m_Impl << "\t" << "Set" << field.GetFriendlyName() << "(" << "GetDefault" << field.GetFriendlyName() << "(), true);" << std::endl;
 	}
 
 	m_Impl << "}" << std::endl << std::endl;