My requirement is to schedule the reports at a particular time and frequency, i.e. weekly, monthly or daily.
This reports should be mailed at specified time with attachment at which it is scheduled.
Thanks in advance
There is a great framework called Hangfire that you can use to schedule tasks in .net:
http://hangfire.io/
You'll need to create your method for running the report and sending the email but you can schedule that task easily with the hangfire framework.
For other alternatives take a look at this blog entry by Hanselman: http://www.hanselman.com/blog/HowToRunBackgroundTasksInASPNET.aspx
You could schedule tasks from within your ASP.NET project using the Revalee open source project.
Revalee is a service that allows you to schedule web callbacks to your web application. In your case, you would schedule a callback that would synchronize your data at a specific time. Revalee works very well with tasks that are discrete transactional actions, like updating some database values or sending an automated email message (read: not long running). The code to perform your action would all reside within your app.
To use Revalee, you would:
Install the Revalee Service, a Windows Service, on your server. The Windows Service is available in the source code (which you would compile yourself), in a precompiled version available at the Revalee website, or via Chocolatey.
Use the Revalee client library in your Visual Studio project. (There is an MVC-specific version too.) The client library is available in the source code (which, again, you would compile yourself) or in a precompiled version available via NuGet.
You would register a future callback when your code calls the ScheduleReportTransmission() method (this example is assuming that you need your action to run 12 hours from now, but it could be any date & time).
Private Sub ScheduleReportTransmission()
Dim callbackTime As DateTimeOffset = DateTimeOffset.Now.AddHours(12.0)
' The callback should be 12 hours from now
Dim callbackUrl As New Uri("http://mywebapp.com/TransmitReport.aspx")
' Register the callback request with the Revalee service
RevaleeRegistrar.ScheduleCallback(callbackTime, callbackUrl)
End Sub
When Revalee calls your application back, your app would perform whatever action you have coded it to do. You do this by adding the following method call (TransmitReport()) to your TransmitReport.aspx page handler, à la:
Private Sub TransmitReport()
' TODO Lookup the report information and send the email
' ...
Return
End Sub
I hope this helps.
Note: The code example above uses a synchronous version of ScheduleCallback(), the Revalee client library also supports asynchronous calls à la:
RevaleeRegistrar.ScheduleCallbackAsync(callbackTime, callbackUrl)
In case it was not clear above, the Revalee Service is not an external 3rd party online scheduler service, but instead a Windows Service that you install and fully control on your own network. It resides and runs on a server of your own choosing, most likely your web server (but this is not a requirement), where it can receive callback registration requests from your ASP.NET application.
Disclaimer: I was one of the developers involved with the Revalee project. To be clear, however, Revalee is free, open source software. The source code is available on GitHub.
Related
I am working on an asp.net mvc-5 web application, deployed under windows 2012 & iis-8. my asp.net mvc have many CRUD operations which are implemented as action methods inside my asp.net mvc.
But my asp.net mvc web application will be doing scheduled long running network scan process, the network scan will mainly do the following steps:-
Get the list of our servers and vms from our database.
Get the scanning username and password for each server and vm from a third party tool, using Rest API.
Call some powershell scripts to retrieve the servers & vms info such as network info, memory, name, etc.
Update our ERP system with the scan info using Rest API.
Now I did a pilot project using the following approach:-
I define a Model method inside my asp.net mvc to do the above 4 steps.
Then I install hangfire tool which will be calling the scan method on predefined scheduler.
Also I create a View inside my asp.net mvc which allow users to set the hangfire schedule settings (this require to do an IIS reset on the host server for hangfire to get the new settings).
Now I run a test scan for a round 150 servers which took around 40 minutes to complete , and it worked well. The only thing I noted is that if I set the schedule to run on non-business hours (where no activity is made on IIS) then hangfire will not be able to call the job, and once the first request is made the missed jobs will run. I overcome this limitation by defining a windows task which calls IIS each 15 minutes, to keep application pool live, and it worked well...
Now the other approach I am reading about is doing my above is as follow:-
Instead of defining Model method inside asp.net mvc to do the scan, I can create a separate console application to do the scan.
Then inside my asp.net mvc to create a view which allow users to create and schdule a task inside the windows tasks scheduler. I can do so by integrating with the windows task scheduler API.
Where this windows task will be calling the console application.
Now I am not sure which approach is better and why ? now generally speaking long running/background jobs should not run under iis.. But at the same time defining these long running processes as console app and calling these apps inside windows task scheduler will create extra dependencies on my web application. And will add extra effort when moving the application from move server to another (for example from test to live)..
Beside this I read that tools such as hangfire, quartz and other are designed to allow running long running tasks inside IIS and they eliminate the need to create console applications and scheduling these console applications using task scheduler ..
So can anyone advice on this?
In my opinion, if it is possible to solve the scheduling problem on the web application side, there is no need to create a scheduler task or a new console application for triggering purposes. The problem you will probably face when using scheduling task in a web application is generally common as you might see is that: The scheduler works like a charm during debugging of the web application, but not being able to trigger after publishing it to IIS. At this point the problem is generally related to IIS rather than the schedulers Quartz.NET, Hangfire, etc. Although there are lots of articles or solution methods posted on the web, unfortunately only some of them is working properly. In addition to this, most of them require lots of configuration settings on the web and machine configuration.
However, there are also some kind of solutions for such a kind of scheduling problem and I believe in that it is worthy to give a try Keep Alive Service For IIS 6.0/7.5. Just install it on the server to which you publish your application and enjoy. Then your published application will be alive after application pool recycling, IIS/Application restarting, etc. That is also used in our MVC application in order to send notification mails weekly and has been worked for months without any problem. Here are the sample code that I use in our MVC application. For more information please visit Scheduled Tasks In ASP.NET With Quartz.Net and Quartz.NET CronTrigger.
*Global.asax:*
protected void Application_Start()
{
JobScheduler.Start();
}
*EmailJob.cs:*
using Quartz;
public class EmailJob : IJob
{
public void Execute(IJobExecutionContext context)
{
SendEmail();
}
}
*JobScheduler.cs:*
using Quartz;
using Quartz.Impl;
public class JobScheduler
{
public static void Start()
{
IScheduler scheduler = StdSchedulerFactory.GetDefaultScheduler();
scheduler.Start();
IJobDetail job = JobBuilder.Create<EmailJob>().Build();
ITrigger trigger = TriggerBuilder.Create()
.WithIdentity("trigger1", "group1")
.StartNow()
.WithSchedule(CronScheduleBuilder
.WeeklyOnDayAndHourAndMinute(DayOfWeek.Monday, 10, 00)
//.WithMisfireHandlingInstructionDoNothing() //Do not fire if the firing is missed
.WithMisfireHandlingInstructionFireAndProceed() //MISFIRE_INSTRUCTION_FIRE_NOW
.InTimeZone(TimeZoneInfo.FindSystemTimeZoneById("GTB Standard Time")) //(GMT+02:00)
)
.Build();
scheduler.ScheduleJob(job, trigger);
}
}
Also I create a View inside my asp.net mvc which allow users to set the hangfire schedule settings (this require to do an IIS reset on the host server for hangfire to get the new settings).
You're resetting your webserver to update a task's schedule? That doesn't sound healthy. What you might do is keep track of what the scheduled time should be, and on execution, check if the current time is within a certain range of the scheduled time (or has already been executed), otherwise abort the job.
The only thing I noted is that if I set the schedule to run on non-business hours (where no activity is made on IIS) then hangfire will not be able to call the job, and once the first request is made the missed jobs will run. I overcome this limitation by defining a windows task which calls IIS each 15 minutes, to keep application pool live, and it worked well...
Hangfire's documentation has a page about running delayed tasks that mentions what you need to change to accomodate this.
Using Windows' Task Scheduler doesn't seem like a good idea; it's not meant for the execution of ad-hoc, short-lived tasks. You probably need elevation to create tasks, and you'd probably need to define another scheduled task to clean up the mountain of tasks that would exist after a few dozen background jobs have been executed.
You're also correct that using Windows' Task Scheduler would make it more difficult to move your application around.
I am working in Asp.Net MVC, i have a scenario as follows.
"Employee will have specific end time to finish a task, once the time is completed, a mail has to be sent automatically to the team lead to notify."
In some way i have to check server datetime and the specified end datetime constantly,my frnd suggested me to check the database datetime with the endtime for every 30 secs by creating a console scheduler to watch the time, do i have any alternative to do this without checking the database frequently?
I would suggest a windows service to check the timings.
do i have any alternative to do this without checking the database
frequently
You could implement some kind of caching mechanism - keep all tasks in memory and check against server time - however if the tasks are updated frequently this cache would quickly become outdated or you need a way to synch the cache with the database.
So I would usethe approach to check every x seconds (30 seconds seems very little, how accurate do you want your notifications to be?? Perhaps once every 5 minutes will be enough depending on your requirements).
If you know the task's end time (that is, the time when the email is supposed to be sent) then I would recommend that you schedule a task to call your ASP.NET MVC application back at the exact moment you need to send the email message. This would allow you to avoid having to 'poll' the server. To do this, I would recommend that you take a look at the Revalee open source project.
Revalee is a service that allows you to schedule web callbacks to your web application. In your case, you would schedule a callback that would send an email message at a specific time. Revalee works very well with tasks that are discrete transactional actions, like sending an automated email message or updating some database values (read: not long running). By using Revalee, the code to perform your action would all reside within your web application.
To use Revalee, you would:
Install the Revalee Service, a Windows Service, on your server. The Windows Service is available in the source code (which you would compile yourself), in a precompiled version available at the Revalee website, or easily installable via Chocolatey.
Use the Revalee client library in your Visual Studio project. (There is an MVC-specific version too.) The client library is available in the source code (which, again, you would compile yourself) or in a precompiled version available via NuGet.
You would register a future callback when you know the end time for the user's task:
private void ScheduleTaskEndEmail(int taskId)
{
// The DetermineTaskEndTime() method is a private method
// (of your creation) which returns a task's end time as
// a DateTimeOffset
DateTimeOffset callbackTime = DetermineTaskEndTime(taskId);
// The callback should at the task's end time
Uri callbackUrl = new Uri(
string.Format(
"http://mywebapp.com/Email/SendTaskEndEmail/{0}",
taskId
)
);
// Register the callback request with the Revalee service
RevaleeRegistrar.ScheduleCallback(callbackTime, callbackUrl);
}
4.When Revalee calls your application back, your app would perform whatever action you have coded it to do. In the Email controller, your SendTaskEndEmail action (see the Uri above) might look like:
[AllowAnonymous]
[CallbackAction]
public ActionResult SendTaskEndEmail(int taskId)
{
// TODO 1. Validate the taskId,
// 2. Lookup the task's information, &
// 3. Send the email message
// ...
return new EmptyResult();
}
The Revalee website has a complete API Reference as well as instructions on how to install and configure the Windows Service. I hope this helps.
Note: The code example above uses a synchronous version of ScheduleCallback(), the Revalee client library also supports asynchronous calls à la:
RevaleeRegistrar.ScheduleCallbackAsync(callbackTime, callbackUrl);
In case it was not clear above, the Revalee Service is not an external 3rd party online scheduler service, but instead a Windows Service that you install and fully control on your own network. It resides and runs on a Windows server of your own choosing where it can receive callback registration requests from your ASP.NET MVC application.
Disclaimer: I was one of the developers involved with the Revalee project. To be clear, however, Revalee is free, open source software (MIT license). The source code is available on GitHub.
I read it was recommended to use regular Windows Services instead, or a Console App you could start with the task scheduler, the issue here is that I won't be able to have access to the server much less to configure it myself after my website is up, so we had come up with the idea of setting up a web service that could do the work automatically at those specific times, I've created a web service already, but I can't see how to make it automatic, so far it's only my website caling the web services methods, which is completely useless since I could do that from the website itself.
This is the example form VS, I can call it from my own code but it serves no purpose.
<WebMethod()> _
Public Function HelloWorld() As String
Return "Hello World"
End Function
So assumming this is what I need, how could I make it automatic?
If what you need is some solution that will run some routine at configured time and provide access to itself via http, you can:
make a web service,
use Quartz.NET http://quartznet.sourceforge.net/ to schedule routine,
use WCF self hosting for providing HTTP access
I am trying to construct a simple windows workflow to monitor a directory for inbound files and do some DB updates using Windows WF 4.0. Currently I am planning to build a 'WCF Workflow Service' and host it as a 'Windows service' running 24/7 (with a daily service shutdown and startup).
Further in the future I am planning to consume this service using an ASP.NET/WPF application to create a basic dashboard kind of stuff.
Considering the idea of directory polling for files with WF hosted on windows service, does it seems to be a good idea? What can be the cons of this?
Please advice if there are any drawbacks on this or can this achieved by better means?
I'm actually doing this, but it is a bit more complex than you think, and should be avoided if possible.
You should not be blocking from within an Activity; if it is expected to be a long running Activity that is waiting from input from the outside (FileSystemWatcher event, for instance), the workflow should idle itself and wait to be woken from the outside.
How I did this was I created a workflow extension that hosted the FileSystemWatcher. Once the Activity was ready to watch for a file, it created a bookmark and passed it to the extension.
The extension then started the FSW, holding onto the bookmark.
When a FSW event was fired, the extension resumed the bookmark, passing in an object that contained details about the event. The Activity did what was needed with the event, then re-scheduled itself.
Normally I wouldn't have done this, but I had some requirements that forced me to use WF4 to accomplish this goal. If I didn't have to use WF4, I would have just spun up the FSW within the service and consumed the events.
Unless you expect to have to be very flexible with your configuration detailing what you do with the FSW event, and expect this to change relatively often during deployment of the service, I'd skip WF4.
Other than using a web service, is there anyway to call a method in a web app from a windows application? Both run on the same machine.
I basically want to schedule a job to run a windows app which updates some file (for a bayesian spam filter), then I want to notify the web app to reload that file.
I know this can be done in other ways but I'm curious to know whether it's possible anyway.
You can make your windows app connect to the web app and do a GET in a page that responds by reloading your file, I don't think it is strictly necessary to use a web service. This way you can also make it happen from a web browser.
A Web Service is the "right" way if you want them to communicate directly. However, I've found it easier in some situations to coordinate via database records. For example, my web app has bulk email capability. To make it work, the web app just leaves a database record behind specifying the email to be sent. The WinApp scans periodically for these records and, when it finds one with an "unprocessed" status, it takes the appropriate action. This works like a charm for me in a very high volume environment.
You cannot quite do this in the other direction only because web apps don't generally sit around in a timing loop (there are ways around this but they aren't worth the effort). Thus, you'll require some type of initiating action to let the web app know when to reload the file. To do this, you could use the following code to do a GET on a page:
WebRequest wrContent = WebRequest.Create("http://www.yourUrl.com/yourpage.aspx");
Stream objStream = wrContent.GetResponse().GetResponseStream();
// I don't think you'll need the stream Reader but I include it for completeness
StreamReader objStreamReader = new StreamReader(objStream);
You'll then reload the file in the PageLoad method whenever this page is opened.
How is the web application loading the file? If you were using a dependency on the Cache object, then simply updating the file will invalidate the Cache entry, causing your code to reload that entry when it is found to be null (or based on the "invalidated" event).
Otherwise, I don't know how you would notify the application to update the file.
An ASP.NET application only exists as an instance to serve a request. This is why web services are an easy way to handle this - the application has been instantiated to serve the service request. If you could be sure the instance existed and got a handle to it, you could use remoting. But without having a concrete handle to an instance of the application, you can't invoke the method directly.
There's plenty of other ways to communicate. You could use a database or some other kind of list which both applications poll and update periodically. There are plenty of asynchronous MQ solutions out there.
So you'll create a page in your webapp specifically for this purpose. Use a Get request and pass in a url parameter. Then in the page_load event check for this paremter. if it exists then do your processing. By passing in the parameter you'll prevent accidental page loads that will cause the file to be uploaded and processed when you don't want it to be.
From the windows app make the url Get request by using the .Net HttpWebRequest. Example here: http://www.codeproject.com/KB/webservices/HttpWebRequest_Response.aspx