I wrote an application that use grpc with ASP.NET client/server.
This application is built for watch and inform about some operations.
Because I would to have an application also compatible with linux, I transformed it in a dll, then for Windows I made a little exe that uses it, with an icon in the systray.
It works for Windows, I must test for linux except for a part, I would to get the addresses used by the server after launching... it works if I back the dll in console mode, but with the short "launcher" it's impossible (add by edit) to get the addresses with the code i wrote between balises, BUT you can connect to the server (by example i changed port in config file to verify if it was not an address by default and it works.). My problem is only to retrieve addresses after launch, i need them to add the possibility to receive a mail with addresses to connect, show them in systray..
Yesterday I found this way to get addresses used:
public void Configure(IApplicationBuilder app,...)
{
string ServerAddress = app.ServerFeatures.Get<IServerAddressesFeature().Addresses.FirstOrDefault();
// ---
}
with the short launcher the string is null while it works when I back transform the dll as a program and launch it.
I would to have an easy way, without to make big modifications when I make an app for a system or another, I have chosen what was the more compatible and would to stay in this way if possible. I know i could make an identifier to know on which system I then launch according to the OS, but i hoped to find another way in case I want to make something else with this app.
Edit:
It seems it could be a problem between the fact to launch a systray that launch Kestrel. I'm beginner with Asp .net. I copy/paste contract and constructor to the systray, it seems i have the same problem (i used a different port). I can connect but IApplicationBuilder don't have the list of adresses used.
Related
I'm trying to write a Tray-Icon application with WPF as a kind of add-on to a telephone software. However my only way of recieving data from said telephone software is by having it automatically execute a URI with parameters (command line or http). Essentially I can freely define the format similar to this:
trayapp.exe --num $caller.number --name $caller.name
When the telephone software recieves a call it'll automatically fill in the parameters and executes the target.
So basically I want a permanently active executable that's running in the background but my only way of getting the necessary info (like caller-number) is by passing it as a command line parameter.
Is there a good way to get the data that's being passed to a URI into my background application? It's not like I can just re-execute the tray-app, or can I? Communication via HTTP (locally!) seems overkill but I just don't know a windows-internal equivalent ...
I have a c# console application that I invoke with a server call in PHP
chdir($filePath);
exec($filePath.$fileName);
This works great, the application is run. The data it is designed to collect is collected and everyone is happy.
Currently I have plans on storing the one time use information on a server or a flat file, but then I noticed that while the console application is running and doing it's magic the page hangs waiting for the application to stop. This intrigued me, and now i'm wondering if there is a way for the application to pass it's data back to the page directly?
Note: I'm running Apache2 on Windows 7
Update:
Ended up using
$runCommand = "D:\\ScanBoyConsole\\ScanBoy_Console.exe COM1 9600 8 1 0 1";
$WshShell = new COM("WScript.Shell");
$output = $WshShell->Exec($runCommand)->StdOut->ReadAll;
json_decode($output);
If you mean by "directly" that you want the application's output sent to the client while it's still running you might be interested in passthru().
If you're also the author of the C# application you could skip the console application and expose the functionality in a way accessible via php's COM and .Net module.
The console app should be able to print (using Console.WriteLine), and PHP can take the results of that...
Back in my PHP days, we called scripts all the time (that are nothing but console apps basically) and had the results spit out to the page.
"shell_exec — Execute command via shell and return the complete output
as a string"
http://php.net/manual/en/function.shell-exec.php
[So, the only difference is that you should use shell_exec instead of a regular exec]
We are currently working on an API for an existing system.
It basically wraps some web-requests as an easy-to-use library that 3rd party companies should be able to use with our product.
As part of the API, there is an event mechanism where the server can call back to the client via a constantly-running socket connection.
To minimize load on the server, we want to only have one connection per computer. Currently there is a socket open per process, and that could eventually cause load problems if you had multiple applications using the API.
So my question is: if we want to deploy our API as a single standalone assembly, what is the best way to fix our problem?
A couple options we thought of:
Write an out of process COM object (don't know if that works in .Net)
Include a second exe file that would be required for events, it would have to single-instance itself, and open a named pipe or something to communicate through multiple processes
Extract this exe file from an embedded resource and execute it
None of those really seem ideal.
Any better ideas?
Do you mean something like Net.TCP port sharing?
You could fix the client-side port while opening your socket, say 45534. Since one port can be opened by only one process, only one process at a time would be able to open socket connection to the server.
Well, there are many ways to solve this as expressed in all the answers and comments, but may be the simpler way you can use is just have global status store in a place accesible for all the users of the current machine (may be you might have various users logged-in on the machine) where you store WHO has the right to have this open. Something like a "lock" as is used to be called. That store can be a field in a local or intranet database, a simple file, or whatever. That way you don't need to build or distribute extra binaries.
When a client connects to your server you create a new thread to handle him (not a process). You can store his IP address in a static dictionary (shared between all threads).
Something like:
static Dictionary<string, TcpClient> clients = new Dictionary<string, TcpClient>();
//This method is executed in a thread
void ProcessRequest(TcpClient client)
{
string ip = null;
//TODO: get client IP address
lock (clients)
{
...
if (clients.ContainsKey(ip))
{
//TODO: Deny connection
return;
}
else
{
clients.Add(ip, client);
}
}
//TODO: Answer the client
}
//TODO: Delete client from list on disconnection
The best solution we've come up with is to create a windows service that opens up a named pipe to manage multiple client processes through one socket connection to the server.
Then our API will be able to detect if the service is running/installed and fall back to creating it's own connection for the client otherwise.
3rd parties can decide if they want to bundle the service with their product or not, but core applications from our system will have it installed.
I will mark this as the answer in a few days if no one has a better option. I was hoping there was a way to execute our assembly as a new process, but all roads to do this do not seem very reliable.
The code I am currently working on runs on Windows Server 2003, but needs to be able to write to EventLogs on multiple machines. I am coding in C#, using VS2008 Pro, and .NET Framework 3.5.
The code itself is relatively simple (thanks to the framework):
using (EventLog remoteEvtLog = new EventLog(LogName, HostName, EventSource))
{
remoteEvtLog.WriteEntry(Body);
}
"LogName" is a string containing the name of the log to write to - in most cases "Application".
"HostName" is a string containing the NetBIOS Name of the machine where the log entry should be written.
"EventSource" is a string containing the name of the event sender (this is a utility used by multiple apps, so usually it will have the name of the consuming application).
"Body" is a string containing the text to be written to the event log.
In most cases this works fine, but when the machine being written to uses UAC, any write which creates a new EventSource fails. This occurs even though the Security credentials used are members of the Administrators group - and I have not been able to find a way to specify the elevated priviledge level. Apparently, members of the Administrators goroup get two tokens - one limited, and one elevated, but as far as I can tell, the only way to specifiy the elevated token is through the UI - which is obviously a problem when remotely accessing the Logs.
Any ideas out there?
Your code is not supposed to create new event sources (the legacy auto-create behavior is unfortunate, but still wrong). If you need a separate event source for your application, then the installer for that application - which runs with elevated administrative privileges - should create it.
I've been really interested in adding support for video podcasts to Media Browser.
I would like users to be able to navigate through the available video podcasts and stream them from the internets. That's really easy cause media player etc.. will happily play a file that lives in the cloud.
The problem is that I want cache these files locally so subsequent viewings of the same episode will not involve streaming and instead will play the local file.
So... I was thinking, why not host an HttpListener and as media player asks it for bits of the file, have the HttpListener download and store it locally. Next time a user plays the file we will already have portions of the file locally.
Does anyone know of example code that uses HttpListener for proxying?
EDIT
The idea would be only to proxy simple streamable content like MP3 or Mov.
The bounty will go to an actual implementation.
Here is the API I would like:
// will proxy a uri on the local port, if cacheFile exists it will resume the
// download from cacheFile.
// while the file is downloading it will be name cacheFile.partial, after the
// download is complete the file will be renamed to cacheFile.
// Example usage: ProxyFile("http://media.railscasts.com/videos/176_searchlogic.mov", 8000, #"c:\downloads\railscasts\176_searchlogic.mov")
//
// Directly after this call http://localhost:8000 will be the proxy stream, it will be playable locally.
void ProxyUri(Uri uri, int port, string cacheFile)
Edit 2
HttpListener is looking pretty unpromising I will probably need to do the work at a TCP socket level as HttpListeners seem to require the program runs as admin which is going to be really tricky.
I hadn't done anything with HttpListener before, so I thought this would be a nice little exercise to bring myself up to speed with it - and so it proved. I implemented it as a single ProxyListener class whose constructor takes the parameters of the ProxyUri function you specified. Once you obtain an instance, you start it listening (and potentially downloading) by calling its Start method. When you're done with it, call Cleanup.
There are one or two rough edges but basically it works as per your question. To test it, I built it up as a console application with a Program class which accepts input lines consisting of (uri, port, filename), space-separated, creates the ProxyListener instances and starts them. You can run this console application, type in a suitable line, and the downloader will start (printing out progress to console). Simultaneously you can e.g. fire up IE and fetch the file from the specified port, and you will be able to download it while the downloader is still working. The "uploader" progress will be printed to console, too.
I'm having a bit of trouble pasting it in here, maybe due to size (it's not that big, but bigger than the snippets you normally see here - the ProxyListener class is a tad under 200 lines). Does it sound interesting? If so, I'll post it to a pastebin and update this answer with a link.
Update: Posted as a gist.
Note that you will need Administrator privileges to run the program, since HttpListener requires this.
Update 2: Under certain circumstances, it is not necessary to have admin privileges to run HttpListener. See this link and this one. The idea is, if you can reserve an URL namespace during installation time, then the user does not have to have admin privileges if listening against that namespace.
Streaming was not designed to be saved, and also these protocols are very custom and very complex to implement, streaming sessions do lots of validation and synchronization which will be extremely difficult to imitate. Of course it is not an impossible task, but its fairly big task to do. Only other way is to read and save it as local media file, and use that as a reference. Because you can use windows media encoder to read stream and write stream data as local file, but it still may not allow you to do copy protected data.
Did you consider using HTTP proxy with caching features?
Like:
Apache httpd with mod_proxy and mod_cache
Squid
See also Web Cache # wikipedia
If you want your application to have such web cache component, I suggest you look for Web Cache implementation in .Net, and not code it from scratch.