/// <summary>
/// The callback function that gets called when the configuration file changes.
///
/// NOTE:
/// OnChanged gets fired multiple times if changes are made using notepad..
/// this is annoying in terms of performance but otherwise doesn't affect the correctness of
/// the program.
/// </summary>
/// <param name="a"></param>
/// <param name="file"></param>
public void ConfigurationFileChangedCallBack
(object a,
FileSystemEventArgs file)
{
try
{
//Read the configuration information using External Storage Reader
//Read the entire XML file and get our part from the file
Global.WriteInfo("Configuration file changed externally...");
ReloadActivatorConfiguration();
}
catch (Exception e)
{
EAException ea = e as EAException;
// if the exception was warning then just report it and ignore the update
if (ea != null && (int)ea.Error < 0)
{
EAException.Report(e);
Global.WriteWarning(
"Configuration file update was ignored because of bad data in it.");
}
else
{
Global.DoHardKill(e);
}
}
}
/// <summary>
/// Recycles the existing log file
/// </summary>
public static void RecycleLog()
{
lock (ms_hardKill)
{
if (ms_outputFile == null)
{
return;
}
// Generate the new file name
DateTime dt = DateTime.Now;
string ext = "." + dt.Year + "." + dt.Month + "." + dt.Day + "." + dt.Hour + "." + dt.Minute + "." + dt.Second + "." + dt.Millisecond;
string NewFileName = ms_appName + ext + OUTPUTEXT;
try
{
// copy the log file to the new log file
File.Copy(ms_outputLogName, NewFileName);
WriteToConsole("The output file was saved as: " + NewFileName);
}
catch (Exception e)
{
WriteToConsole("Cannot save the existing output file as: " + NewFileName + ". The output file is preserved");
EAException.Report(e);
}
// truncate the current log file
ms_outputFile.SetLength(0);
}
}
/// <summary>
// Installs the Windows NT Service. Uses a transacted installer, so that
// if installation fails midstream for some reason, installation is rolled
// back. Post installation, the registry settings for the service are modified
// to change the command-line parameters (because currently, CLR does not allow it)
// If registry modification fails for some reason, uninstall is called on the service.
/// </summary>
/// <param name="svcname">Service to install</param>
/// <param name="username">User name to execute under</param>
/// <param name="password">Password of the user</param>
public static void Install(
string svcname,
string username,
string password)
{
bool doUninstall = false;
try
{
Global.WriteStatus("External Activator is installing as NT service '" + svcname + "' ...");
TransactedInstaller ti = new TransactedInstaller();
// Sets information required for installing (might get username and password information from the user)
ProjectInstaller mi = new ProjectInstaller(svcname, username, password);
ti.Installers.Add(mi);
String path = String.Format("/assemblypath={0}",
System.Reflection.Assembly.GetExecutingAssembly().Location);
String[] cmdline = { path };
InstallContext ctx = new InstallContext(String.Format(svcname + ".InstallLog"), cmdline);
ti.Context = ctx;
// Starts the installation process
ti.Install(new Hashtable());
doUninstall = true;
// Registry modification of Command-Line arguments to include (-svc) followed by the service name
// to install it as a particular External Activator.
RegistryKey key = Registry.LocalMachine.OpenSubKey(String.Format("System\\CurrentControlSet\\Services\\{0}", svcname), true);
object ImagePathObject = key.GetValue("ImagePath");
if (ImagePathObject != null)
{
Global.WriteDebugInfo("Modifying the registry to include command-line parameters after installation.");
string ImagePath = String.Format("{0} /{1}:{2}", (string)ImagePathObject, CommandLineArgument.RunAsNTServiceArgument, svcname);
key.SetValue("ImagePath", ImagePath);
}
else
{
// Calls Uninstall if registry modification not possible
throw new EAException("Critical Error : Could not open ImagePath key of NT service '" + svcname + "' in the registry. Uninstalling service", Error.postInstallProblem);
}
Global.WriteStatus("External Activator is successfully installed as NT service '" + svcname + "' ...");
}
catch (Exception e)
{
if (doUninstall)
{
try
{
NTService.Uninstall(svcname);
}
catch (Exception eNested)
{
EAException.Report(eNested);
}
}
throw new EAException("External Activation Installation failed", Error.installProblem, e);
}
}
public static void DoHardKill(
Exception e)
{
ms_logMgr.UncleanShutdown();
EAException.Report(e, true);
WriteError("External activator was abruptly terminated.");
EAException ea = e as EAException;
if (ea != null)
{
System.Environment.Exit((int)ea.Error);
}
System.Environment.Exit((int)Error.unexpectedError);
}
/// <summary>
/// Performs necessary initialization of the External Activation NT Service so that it can start
/// doing its work.
/// </summary>
/// <param name="args"></param>
protected override void OnStart(
string[] args) // I optional startup arguments
{
try
{
if (Global.Shutdown == false)
{
Global.BootExternalActivator();
return;
}
}
catch (Exception e)
{
Global.SetShutdown();
EAException.Report(e);
}
StopService(new ServiceController(this.ServiceName), new TimeSpan(1));
return;
}
/// <summary>
/// Connects to the sql server and database and run the service
/// </summary>
public static void Start(
ConfigurationManager configMgr)
{
Global.WriteDebugInfo("Starting up the Notification service...");
configMgr.GetNotificationService(
ref ms_notificationSQLServer,
ref ms_notificationDatabase,
ref ms_notificationService);
ms_connected = false;
ms_connecting = false;
ms_error = null;
NotificationService ns = null;
SqlConnection connection = null;
int waiting_time = 1000;
int retry = 0;
while (true)
{
bool fFailedToConnect = false;
// define a connection if needed
if (connection == null)
{
connection = new SqlConnection(
String.Format("server={0};Integrated security=true;database={1};Connect Timeout=10;Application Name=External activator",
ms_notificationSQLServer,
ms_notificationDatabase));
ns = null;
}
// if connection is up, do not establish again. Else, establish a connection
// Always started the first time
if (connection.State != ConnectionState.Open)
{
try
{
ms_connecting = true;
connection.Open();
}
catch (SqlException e)
{
if (ms_error != e.Message)
{
ms_error = e.Message;
Global.WriteWarning(
"Failed to connect to Notification SQL Server '" + ms_notificationSQLServer + "' and Database: '" + ms_notificationDatabase +
"' because: " + e.Message);
}
else
{
Global.WriteDebugInfo(
"Failed to connect to Notification SQL Server '" + ms_notificationSQLServer + "' and Database: '" + ms_notificationDatabase +
"' because: " + e.Message);
}
connection.Dispose();
connection = null;
fFailedToConnect = true;
}
ms_connecting = false;
if (fFailedToConnect)
{
// Implement an exponential back-off rate of connecting (else this might
// overflow the EventLog and other logs
waiting_time *= 2;
if (waiting_time > Global.MAX_WAITING_TIME)
{
waiting_time = Global.MAX_WAITING_TIME;
}
Thread.Sleep(waiting_time);
continue;
}
Global.WriteInfo("Connection to notification SQL server '" + ms_notificationSQLServer + "' and database '" + ms_notificationDatabase + "' is established.");
waiting_time = 1000;
ms_error = null;
ms_connected = true;
}
// create a notification service is one does not exist
if (ns == null)
{
try
{
ns = new NotificationService(
ms_notificationService,
connection,
configMgr);
}
catch (ArgumentException e)
{
// if bad parameters were provided then
// report the problem and retry later
if (ms_error != e.Message)
{
Global.WriteWarning(e.Message);
ms_error = e.Message;
}
else
{
Global.WriteDebugInfo(e.Message);
}
fFailedToConnect = true;
}
if (fFailedToConnect)
{
waiting_time *= 2;
if (waiting_time > Global.MAX_WAITING_TIME)
{
waiting_time = Global.MAX_WAITING_TIME;
}
Thread.Sleep(waiting_time);
continue;
}
waiting_time = 1000;
}
// now receive all the messages for this service and
// end the application
ns.WaitforTimeout = TimeSpan.FromSeconds(-1);
ns.FetchSize = 1;
bool fRestart = false;
Global.WriteInfo("Notification service '" + ms_notificationService + "' is started.");
try
{
ns.Run(true, connection, null);
}
catch (ServiceException e)
{
Global.WriteWarning("Service exception occured while running. External activator will try to reconnect.");
if (retry == 3)
{
Global.DoHardKill(e);
}
EAException.Report(e);
fRestart = true;
}
catch (SqlException e)
{
Global.WriteWarning("Service exception occured while running. External activator will try to reconnect.");
if (retry == 3)
{
Global.DoHardKill(e);
}
EAException.Report(e);
fRestart = true;
}
catch (Exception e)
{
Global.DoHardKill(e);
}
if (fRestart)
{
retry++;
// reset the state and retry again
ms_connected = false;
ms_connecting = false;
ms_error = null;
waiting_time = 1000;
ns = null;
connection.Close();
connection = null;
continue;
}
connection.Close();
return;
}
}