Merge pull request #6511 from Icinga/feature/apilistener-dynamic-port

ApiListener: Add support for dynamic port handling

doc/16-upgrading-icinga-2.md

@@ -37,6 +37,12 @@ has been removed and this setting has no effect.
 >
 > This is important if you rely on the sysconfig configuration in your own scripts.
 
+### New Constants <a id="upgrading-to-2-10-path-new-constants"></a>
+
+New [Icinga constants](17-language-reference.md#icinga-constants) have been added in this release.
+
+* `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>
 
 ### Deprecation and Removal Notes <a id="upgrading-to-2-9-deprecation-removal-notes"></a>

doc/17-language-reference.md

@@ -409,8 +409,10 @@ Vars                |**Read-write.** Contains a dictionary with global custom at
 NodeName            |**Read-write.** Contains the cluster node name. Set to the local hostname 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`.
+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.
 
 Application runtime details:
 

lib/base/socket.cpp

@@ -114,9 +114,21 @@ int Socket::GetError() const
 /**
  * Formats a sockaddr in a human-readable way.
  *
- * @returns A String describing the sockaddr.
+ * @returns A pair of host and service.
  */
-String Socket::GetAddressFromSockaddr(sockaddr *address, socklen_t len)
+String Socket::GetHumanReadableAddress(const std::pair<String, String>& socketDetails)
+{
+	std::ostringstream s;
+	s << "[" << socketDetails.first << "]:" << socketDetails.second;
+	return s.str();
+}
+
+/**
+ * Returns host and service as pair.
+ *
+ * @returns A pair with host and service.
+ */
+std::pair<String, String> Socket::GetDetailsFromSockaddr(sockaddr *address, socklen_t len)
 {
 	char host[NI_MAXHOST];
 	char service[NI_MAXSERV];
@@ -140,17 +152,15 @@ String Socket::GetAddressFromSockaddr(sockaddr *address, socklen_t len)
 #endif /* _WIN32 */
 	}
 
-	std::ostringstream s;
-	s << "[" << host << "]:" << service;
-	return s.str();
+	return std::make_pair(host, service);
 }
 
 /**
- * Returns a String describing the local address of the socket.
+ * Returns a pair describing the local host and service of the socket.
  *
- * @returns A String describing the local address.
+ * @returns A pair describing the local host and service.
  */
-String Socket::GetClientAddress()
+std::pair<String, String> Socket::GetClientAddressDetails()
 {
 	boost::mutex::scoped_lock lock(m_SocketMutex);
 
@@ -175,22 +185,32 @@ String Socket::GetClientAddress()
 #endif /* _WIN32 */
 	}
 
-	String address;
+	std::pair<String, String> details;
 	try {
-		address = GetAddressFromSockaddr((sockaddr *)&sin, len);
+		details = GetDetailsFromSockaddr((sockaddr *)&sin, len);
 	} catch (const std::exception&) {
 		/* already logged */
 	}
 
-	return address;
+	return details;
 }
 
 /**
- * Returns a String describing the peer address of the socket.
+ * Returns a String describing the local address of the socket.
  *
- * @returns A String describing the peer address.
+ * @returns A String describing the local address.
  */
-String Socket::GetPeerAddress()
+String Socket::GetClientAddress()
+{
+	return GetHumanReadableAddress(GetClientAddressDetails());
+}
+
+/**
+ * Returns a pair describing the peer host and service of the socket.
+ *
+ * @returns A pair describing the peer host and service.
+ */
+std::pair<String, String> Socket::GetPeerAddressDetails()
 {
 	boost::mutex::scoped_lock lock(m_SocketMutex);
 
@@ -215,14 +235,24 @@ String Socket::GetPeerAddress()
 #endif /* _WIN32 */
 	}
 
-	String address;
+	std::pair<String, String> details;
 	try {
-		address = GetAddressFromSockaddr((sockaddr *)&sin, len);
+		details = GetDetailsFromSockaddr((sockaddr *)&sin, len);
 	} catch (const std::exception&) {
 		/* already logged */
 	}
 
-	return address;
+	return details;
+}
+
+/**
+ * Returns a String describing the peer address of the socket.
+ *
+ * @returns A String describing the peer address.
+ */
+String Socket::GetPeerAddress()
+{
+	return GetHumanReadableAddress(GetPeerAddressDetails());
 }
 
 /**
@@ -415,4 +445,3 @@ void Socket::SocketPair(SOCKET s[2])
 			<< boost::errinfo_api_function("socketpair")
 			<< boost::errinfo_errno(errno));
 }
-

lib/base/socket.hpp

@@ -45,7 +45,9 @@ public:
 
 	void Close();
 
+	std::pair<String, String> GetClientAddressDetails();
 	String GetClientAddress();
+	std::pair<String, String> GetPeerAddressDetails();
 	String GetPeerAddress();
 
 	size_t Read(void *buffer, size_t size);
@@ -70,7 +72,8 @@ protected:
 private:
 	SOCKET m_FD{INVALID_SOCKET}; /**< The socket descriptor. */
 
-	static String GetAddressFromSockaddr(sockaddr *address, socklen_t len);
+	static std::pair<String, String> GetDetailsFromSockaddr(sockaddr *address, socklen_t len);
+	static String GetHumanReadableAddress(const std::pair<String, String>& socketDetails);
 };
 
 class socket_error : virtual public std::exception, virtual public boost::exception { };

lib/remote/apilistener.cpp

@@ -264,8 +264,12 @@ void ApiListener::Stop(bool runtimeDeleted)
 	Log(LogInformation, "ApiListener")
 		<< "'" << GetName() << "' stopped.";
 
-	boost::mutex::scoped_lock lock(m_LogLock);
-	CloseLogFile();
+	{
+		boost::mutex::scoped_lock lock(m_LogLock);
+		CloseLogFile();
+	}
+
+	RemoveStatusFile();
 }
 
 ApiListener::Ptr ApiListener::GetInstance()
@@ -318,9 +322,6 @@ bool ApiListener::AddListener(const String& node, const String& service)
 		return false;
 	}
 
-	Log(LogInformation, "ApiListener")
-		<< "Adding new listener on port '" << service << "'";
-
 	TcpSocket::Ptr server = new TcpSocket();
 
 	try {
@@ -331,11 +332,16 @@ bool ApiListener::AddListener(const String& node, const String& service)
 		return false;
 	}
 
+	Log(LogInformation, "ApiListener")
+		<< "Started new listener on '" << server->GetClientAddress() << "'";
+
 	std::thread thread(std::bind(&ApiListener::ListenerThreadProc, this, server));
 	thread.detach();
 
 	m_Servers.insert(server);
 
+	UpdateStatusFile(server);
+
 	return true;
 }
 
@@ -1469,3 +1475,28 @@ String ApiListener::GetFromZoneName(const Zone::Ptr& fromZone)
 
 	return fromZoneName;
 }
+
+void ApiListener::UpdateStatusFile(TcpSocket::Ptr socket)
+{
+	String path = Application::GetConst("CacheDir") + "/api-state.json";
+	std::pair<String, String> details = socket->GetClientAddressDetails();
+
+	Utility::SaveJsonFile(path, 0644, new Dictionary({
+		{"host", details.first},
+		{"port", details.second}
+	}));
+}
+
+void ApiListener::RemoveStatusFile()
+{
+	String path = Application::GetConst("CacheDir") + "/api-state.json";
+
+	if (Utility::PathExists(path)) {
+		if (unlink(path.CStr()) < 0 && errno != ENOENT) {
+			BOOST_THROW_EXCEPTION(posix_error()
+				<< boost::errinfo_api_function("unlink")
+				<< boost::errinfo_errno(errno)
+				<< boost::errinfo_file_name(path));
+		}
+	}
+}

lib/remote/apilistener.hpp

@@ -163,6 +163,9 @@ private:
 
 	static void CopyCertificateFile(const String& oldCertPath, const String& newCertPath);
 
+	void UpdateStatusFile(TcpSocket::Ptr socket);
+	void RemoveStatusFile();
+
 	/* filesync */
 	static ConfigDirInformation LoadConfigDir(const String& dir);
 	static Dictionary::Ptr MergeConfigUpdate(const ConfigDirInformation& config);

lib/remote/apilistener.ti

@@ -41,9 +41,11 @@ class ApiListener : ConfigObject
 		default {{{ return "TLSv1"; }}}
 	};
 
-	[config] String bind_host;
+	[config] String bind_host {
+		default {{{ return Application::GetConst("ApiBindHost"); }}}
+	};
 	[config] String bind_port {
-		default {{{ return "5665"; }}}
+		default {{{ return Application::GetConst("ApiBindPort", "5665"); }}}
 	};
 
 	[config] bool accept_config;