API Package: Repair active stage from local directory; avoid exceptions

This partially reverts #7150 and adds new creation/repair methods.

lib/cli/daemoncommand.cpp

@@ -288,6 +288,9 @@ int DaemonCommand::Run(const po::variables_map& vm, const std::vector<std::strin
 		Logger::DisableConsoleLog();
 	}
 
+	/* Create the internal API object storage. Do this here too with setups without API. */
+	ConfigObjectUtility::CreateStorage();
+
 	/* Remove ignored Downtime/Comment objects. */
 	try {
 		String configDir = ConfigObjectUtility::GetConfigDir();

lib/remote/apilistener.cpp

@@ -7,6 +7,7 @@
 #include "remote/jsonrpc.hpp"
 #include "remote/apifunction.hpp"
 #include "remote/configpackageutility.hpp"
+#include "remote/configobjectutility.hpp"
 #include "base/convert.hpp"
 #include "base/defer.hpp"
 #include "base/io-engine.hpp"
@@ -135,6 +136,9 @@ void ApiListener::OnConfigLoaded()
 		Log(LogWarning, "ApiListener", "Please read the upgrading documentation for v2.8: https://icinga.com/docs/icinga2/latest/doc/16-upgrading-icinga-2/");
 	}
 
+	/* Create the internal API object storage. */
+	ConfigObjectUtility::CreateStorage();
+
 	/* Cache API packages and their active stage name. */
 	UpdateActivePackageStagesCache();
 

lib/remote/configobjectutility.cpp

@@ -10,15 +10,21 @@
 #include "base/dependencygraph.hpp"
 #include "base/utility.hpp"
 #include <boost/algorithm/string/case_conv.hpp>
+#include <boost/filesystem.hpp>
+#include <boost/system/error_code.hpp>
 #include <fstream>
 
 using namespace icinga;
 
 String ConfigObjectUtility::GetConfigDir()
 {
-	/* This may throw an exception the caller above must handle. */
-	return ConfigPackageUtility::GetPackageDir() + "/_api/" +
-		ConfigPackageUtility::GetActiveStage("_api");
+	String prefix = ConfigPackageUtility::GetPackageDir() + "/_api/";
+	String activeStage = ConfigPackageUtility::GetActiveStage("_api");
+
+	if (activeStage.IsEmpty())
+		RepairPackage("_api");
+
+	return prefix + activeStage;
 }
 
 String ConfigObjectUtility::GetObjectConfigPath(const Type::Ptr& type, const String& fullName)
@@ -33,6 +39,57 @@ String ConfigObjectUtility::GetObjectConfigPath(const Type::Ptr& type, const Str
 		"/" + EscapeName(fullName) + ".conf";
 }
 
+void ConfigObjectUtility::RepairPackage(const String& package)
+{
+	String activeStage = ConfigPackageUtility::GetActiveStage("_api");
+
+	/* Try to fix the active stage, whenever we find a directory in there. */
+	if (activeStage.IsEmpty()) {
+		namespace fs = boost::filesystem;
+
+		fs::path path(ConfigPackageUtility::GetPackageDir() + "/_api/");
+
+		fs::recursive_directory_iterator end;
+
+		String foundActiveStage;
+
+		for (fs::recursive_directory_iterator it(path); it != end; it++) {
+			boost::system::error_code ec;
+
+			const fs::path d = *it;
+			if (fs::is_directory(d, ec)) {
+				foundActiveStage = d.string();
+
+				break; //Use the first found directory.
+			}
+		}
+
+		if (!foundActiveStage.IsEmpty()) {
+			ConfigPackageUtility::ActivateStage("_api", foundActiveStage);
+		} else {
+			Log(LogCritical, "ConfigObjectUtility")
+				<< "Cannot repair internal _api package, no directories.";
+			/* TODO: Should be rmdir _api and re-create it? */
+		}
+
+	}
+}
+
+void ConfigObjectUtility::CreateStorage()
+{
+	boost::mutex::scoped_lock lock(ConfigPackageUtility::GetStaticPackageMutex());
+
+	if (!ConfigPackageUtility::PackageExists("_api")) {
+		Log(LogWarning, "ConfigObjectUtility")
+			<< "Package _api doesn't exist yet, creating it.";
+
+		ConfigPackageUtility::CreatePackage("_api");
+
+		String stage = ConfigPackageUtility::CreateStage("_api");
+		ConfigPackageUtility::ActivateStage("_api", stage);
+	}
+}
+
 String ConfigObjectUtility::EscapeName(const String& name)
 {
 	return Utility::EscapeString(name, "<>:\"/\\|?*", true);
@@ -88,16 +145,7 @@ String ConfigObjectUtility::CreateObjectConfig(const Type::Ptr& type, const Stri
 bool ConfigObjectUtility::CreateObject(const Type::Ptr& type, const String& fullName,
 	const String& config, const Array::Ptr& errors, const Array::Ptr& diagnosticInformation)
 {
-	{
-		boost::mutex::scoped_lock lock(ConfigPackageUtility::GetStaticPackageMutex());
-
-		if (!ConfigPackageUtility::PackageExists("_api")) {
-			ConfigPackageUtility::CreatePackage("_api");
-
-			String stage = ConfigPackageUtility::CreateStage("_api");
-			ConfigPackageUtility::ActivateStage("_api", stage);
-		}
-	}
+	CreateStorage();
 
 	ConfigItem::Ptr item = ConfigItem::GetByTypeAndName(type, fullName);
 

lib/remote/configobjectutility.hpp

@@ -23,6 +23,8 @@ class ConfigObjectUtility
 public:
 	static String GetConfigDir();
 	static String GetObjectConfigPath(const Type::Ptr& type, const String& fullName);
+	static void RepairPackage(const String& package);
+	static void CreateStorage();
 
 	static String CreateObjectConfig(const Type::Ptr& type, const String& fullName,
 		bool ignoreOnError, const Array::Ptr& templates, const Dictionary::Ptr& attrs);

lib/remote/configpackageutility.cpp

@@ -265,7 +265,7 @@ String ConfigPackageUtility::GetActiveStageFromFile(const String& packageName)
 	fp.close();
 
 	if (fp.fail())
-		BOOST_THROW_EXCEPTION(std::invalid_argument("Cannot detect active stage for package '" + packageName + "'. Broken config package, check the troubleshooting documentation."));
+		return ""; /* Don't use exceptions here. The caller must deal with empty stages at this point. Happens on initial package creation for example. */
 
 	return stage.Trim();
 }
@@ -283,13 +283,16 @@ void ConfigPackageUtility::SetActiveStageToFile(const String& packageName, const
 
 String ConfigPackageUtility::GetActiveStage(const String& packageName)
 {
+	String activeStage;
+
 	ApiListener::Ptr listener = ApiListener::GetInstance();
 
-	/* config packages without API make no sense. */
+	/* If we don't have an API feature, just use the file storage without caching this.
+	 * This happens when ScheduledDowntime objects generate Downtime objects.
+	 * TODO: Make the API a first class citizen.
+	 */
 	if (!listener)
-		BOOST_THROW_EXCEPTION(std::invalid_argument("No ApiListener instance configured."));
-
-	String activeStage;
+		return GetActiveStageFromFile(packageName);
 
 	/* First use runtime state. */
 	try {
@@ -301,25 +304,23 @@ String ConfigPackageUtility::GetActiveStage(const String& packageName)
 		/* When we've read something, correct memory. */
 		if (!activeStage.IsEmpty())
 			listener->SetActivePackageStage(packageName, activeStage);
-		else
-			BOOST_THROW_EXCEPTION(std::invalid_argument("Cannot detect active stage for package '" + packageName + "'. Broken config package, check the troubleshooting documentation."));
 	}
 
 	return activeStage;
 }
 
 void ConfigPackageUtility::SetActiveStage(const String& packageName, const String& stageName)
 {
+	/* Update the marker on disk for restarts. */
+	SetActiveStageToFile(packageName, stageName);
+
 	ApiListener::Ptr listener = ApiListener::GetInstance();
 
-	/* config packages without API make no sense. */
+	/* No API, no caching. */
 	if (!listener)
-		BOOST_THROW_EXCEPTION(std::invalid_argument("No ApiListener instance configured."));
+		return;
 
 	listener->SetActivePackageStage(packageName, stageName);
-
-	/* Also update the marker on disk for restarts. */
-	SetActiveStageToFile(packageName, stageName);
 }
 
 std::vector<std::pair<String, bool> > ConfigPackageUtility::GetFiles(const String& packageName, const String& stageName)