I am penning down the features that a remote logging
library might need when built from scratch.
I looked up this: http://www.aggsoft.com/serial-data-logger.htm
I wish to know that what differences can be between a
remote logging library and a remote logger software.
Few things that I thought of:
1. The library can be used in C++ programs to log error messages on the fly.
2. The library will require programming knowledge on the end user's part.
3. The software cannot be used "inside" a C++ program, so we won't be able to log the error messages on the fly? Not sure about this one.
I would like to know that besides logging error messages, what are the things for which it makes sense to use the remote logging library? Sharing big files? Anything else than these two things?
Secondly which is better in what way out of a library and a software - in the current case?
As I mentioned in the my comments to your question, I would think that a logging library would provide some sort of an API/SDK, whereas remote software would not. The same would hold true if its sending messages via TCP/UDP or a serial port. The difference between the 2 options would be how much coding you would have to do. That is, how much would you have to reinvent the wheel?
IMHO, nearly all debug environment/tools support redirect the console output the serial port (using print, or other API). It usually not a a task of Application programmer.
There are other methods for "remote logging":
1) syslog, syslog-ng 's remote service
2) save log local, fetch using ftp
Related
Is it possible to use a Go API in a Qt C++ project?
I would like to use the following Google API written in Go: https://cloud.google.com/speech-to-text/docs/reference/libraries#client-libraries-install-go
Is it possible to use a Go API in a Qt C++ project?
It could be possible, but it might not be easy and would be very brittle to run Go and Qt code in the same process, since Go and Qt have very different thread (goroutine) and memory models.
However, Go has (in its standard library) many powerful packages to ease the development of server programs, in particular of HTTP or JSONRPC servers.
Perhaps you might consider running two different processes using inter-process communication facilities. Details are operating system specific. I assume you run Linux. Your Qt application could then start the Go program using QProcess and later communicate with it (behaving as a client to your Go specialized "server"-like program).
Then you could use HTTP or JSONRPC to remotely call your Go functions from your Qt application. You need some HTTP client library in Qt (it is there already under Qt Network, and you might also use libcurl) or some JSONRPC client library. Your Go program would be some specialized HTTP or JSONRPC server (and some Google Speech to Text client) and your Qt program would be its only client (and would start it). So your Go program would be some specialized proxy. You could even use pipe(7)-s, unix(7) sockets, or fifo(7)-s to increase the "privacy" of the communication channel.
If the Google Speech to Text API is huge (but it probably is not) you might use Go reflective or introspective abilities to generate some C++ glue code for Qt: go/ast, go/build, go/parser, go/importer, etc
BTW, it seems that Google Speech to Text protocol is using JSON with HTTP (it seems to be some Web API) and has a documented REST API, so you might directly code in C++ the relevant code doing that (of course you need to understand all the details of the protocol: relevant HTTP requests and JSON formats), without any Go code (or process). If you go that route, I recommend making your Qt (or C++) code for Google Speech to Text some separate free software library (to be able to get feedback and help from outside).
How does ZeroC ICE compare to 0MQ? I know that 0MQ/Crossroads and DDS are very similar, but cant seem to figure out where ICE comes in.
I need to quickly implement a system that offloads real-time market-data from C++ to C#, as a first phase of my project. The next phase will be to implement an Event Based architecture with an underlying Pub/Sub design.
I am willing to use TCP.. but the the system is currently running on a single 24 core server.. so an IPC option would be nice. From what I understand ICE is only TCP, while DDS and 0mq have an IPC option.
Currently ,I am leaning towards using Protobuf with either ICE or Crossroads IO. Got turned off from the OpenSplice DDS website. Ive done lots research on the various options, was originally considering OpenMPI + boost:mpi, but there does not seem to be MPI for .NET.
My question is:
How does ICE compare to 0MQ? I cant wrap my head around this. Was unable to find anything online that compares the two.
thanks in advance.
........
More about my project:
Currently using CMAKE C++ on Windows, but the plan is to move to CentOS at some point. An additional desired feature is to store the tic data and all the messages in a "NoSql" database such as Hbase/Hadoop or HDF5. Do any of these middleware/messaging/pub-sub libraries have any database integration?
Some thoughts about ZeroC:
Very fast; Able to have multiple endpoints; Able to load balance on the endpoints; Able to reconnect to a different endpoint in case one of the node goes down. This is transparent to the end user; Has good tool chain (IceGrid, IceStorm, IceBox, etc); Distributed, high availability, multiple failover, etc
Apart from that, I have used it for hot swapping code modules (something similar to Erlang) by having the client create the proxy with multiple endpoints, and later on bring down each endpoint for a quick upgrade one by one. With the transparent retry to a different endpoint, I could have the system up and running the whole time i did an upgrade. Not sure if this is an advertised feature or an unadvertised side-effect :)
Overall, it is very easy to scale out your servers if need be using ZeroC Ice.
I know ZeroMQ provides a fantastic set of tools and messaging patterns and I would keep using it for my pet projects. However, The problem that i see is that it is very easy to go overboard and lose track of all your distributed components. This is a must have in a distributed environment. How will you know where your clients/server are when you need to upgrade? If one of components down the chain does not receive a message, how to identify where the issue is? the publisher? the client? or any one of the bridges (REP/REQ, XREP/XREQ, etc) in between?
Overall, ZeroC provides a much better toolset and ecosystem for enterprise solutions.
And it is open source :)
Jaybny,
ZMQ:
If you want real good performance and the only job for Phase 1 of your job is to move data from C++ to C#, then Zmq is the best option.
Having a pub/sub model for event driven architecture is also something that Zmq can help you with, with its in-built messaging pattern.
Zmq also supports your IPC requirements in this case. Eg: you can have one instance of your application that consumes 24 cores by multithreading and communicating via IPC.
ZeroC Ice:
Ice is a RPC framework very much like CORBA.
Eg.
Socket/ZMQ - You send message over the wire. Read it at the other end, parse the message, do some action, etc.
ZeroC Ice - Create a contract between client and server. Contract is nothing but a template of a class. Now the client calls a proxy method of that class, and the server implements/actions it and returns the value. Thus, int result = mathClass.Add(10,20) is what the client calls. The method, parameters, etc is marshalled and sent to the server, server implements the Add method, returns the result, and the client gets 30 as the result. Thus on the client side, the api is nothing but a proxy for a servant running on a remote host.
Conclusion:
ZeroC ICE has some nice enterprisy features which are really good. However, for your project requirements, ZMQ is the right tool.
Hope this helps.
For me.. the correct answer was Crossroads I/O . It does everything I need.. but still unable to pub/sub when using protobufs... im sure ZeroC ICE is great for distributed IPC, but 0MQ/Crossroads, gives you the added flexibility to use Inter-Thread-Communication.
Note: on windows, 0mq does not have IPC.
So, all in all, the crossroads fork of 0mq is the best. but you will have to roll your own windows/ipc (or use tcp::127..) , and publisher side topic filtering features for pub/sub.
nanomsg, from the guy who wrote crossroads and 0mq (i think).
http://nanomsg.org/
Im looking for code that connects to another computer via remote desktop connection and checks if the connection was successful or not.
I packet logged and found out there was a galaxy worth of packets so i was wondering if there was some easy code out there.
There really isn't anything easy about RDP, that protocol stack is huge and builds on the ITU OSI protocols, which includes a fair amount of ASN.1/BER.
Your best bet is the code that's in FreeRDP.
A bit of terminology: you want a "RDP client library for C++".
As others have mentioned, look into the "FreeRDP" and "rdesktop" projects.
With FreeRDP, you're going to get a suite of libraries (each one doing it's thing). With rdesktop, you're going to get a client app (which you have to break the C code out of, and "build" your C++ api around).
If this is a new project, I'd pick FreeRDP over rdesktop, as they have libraries available with your C++ interface already in place.
Do you need to check if an RDP server is present, but not authenticate? In this case all you'd need are the first couple of packets used to negotiate protocol security. You can find the code in FreeRDP in libfreerdp-core/nego.c.
#Blanker1231 : You should have look on rdesktop code , its in c but can be very easily modified to be used in a C++ code , all you have to do is bridge their Struct Stream effectively .
moreover I have worked on a Rdp 7+ implementation ages ago in qt/c++ for a , so recently just for fun of it i used all of my experience and wrote a RDP parser and code generator and open sourced it on https://github.com/shashanksingh/Code-Generator-for-RDP
Right now it dead simple and i am still working on it more intelligent . Word of caution it doesn't generate everything . Examples includes demo.def which on compilation will generate all the class os ms-fscc used in ms-rdp
#Blanker1231 if you ever feel like , just fork the implementation and start pushing stuff in
My main goal is to create an advanced program for manipulating the packets that route within my network via the router. Let my program have total control over the router. Set the download/upload speeds to my inputs, apply the effect to certain devices within in my network. Block upload or download traffic. Set second delay for either the upload or download speed. Specify % of loss packets, and the list goes on.
The problem is that I don't know where to start. I know most languages at the very most basic level. I'd like to create this program in either C, C++ or C# but I don't know yet. What else do I need to know before creating this program? Winsock or something? Winpcap APIs?
This goal is my motivation to learn programming to the extreme, and I'm really looking forward to it.
Thanks in advance!
Hmmm I guess you would want to look at pcap(?):
pcap
Check out:
http://beej.us/guide/bgnet/html/multi/index.html
'Beej's Guide to Network Programming
Using Internet Sockets'
All you could possibly need to know about programming sockets for capture and manipulation.
If I were you I'd write it in C, I'm writing a similar project at the moment in C++ and it's hell but too late to stop and start again.
Hope that helps.
Bear in mind that you either need a router that you can re-program or you need to use your PC as a router to do this.
Either way you want to look into how IPTABLES are implemented.
I've never seen Desktop Windows used as a router only Windows Server, though it may still be possible. libpcap is for packet capture, but not interception as I understand it. Programs like Wireshark use it to monitor copies of packets, but not to modify them. If you want to attempt this, my impression has been that there is a lot more documentation and tools for doing something like this with NetFilter/IPTables on Linux. You can even install something like OpenWRT on a compatible router and get a small, cheap Linux router, though having Desktop Linux will probably help for development. The NetFilter QUEUE library can be used with some IPTables firewall rules to redirects specific (or all) packets to a regular user program. That program can then read the packet and modify it or even request it to be dropped.
http://www.netfilter.org/projects/libnetfilter_queue/
If you want to manipulate network traffic on a Windows machine (as you mentioned), you will need some extra software. This operating system wont give you the full control over itself, which is fine for some reasons.
I think what you want to do, should be done with either winpcap or win10pcap if you are using Win10. These packages contains a windows driver and the libpcap user space library.
i would like to develop a c++ application that would list all url accessed with its response time within the pc. this probably would be transparent to the user, so it would be a dll.
can anyone gve me some sample codes or tutorials on th said matter.
or any tips and suggestion?!..
thanks alot:))
You should take a look at the fiddler plug-ins. This is not a trivial exercise. You need to do dependency injection to capture the wininet calls. Even so not all apps use the high level windows api to initiate connections. Applications that make TCP connections might last for a long time since not all TCP calls are simple web requests.
As Byron has said, this is a non-trivial exercise. You could do it using libpcap http://sourceforge.net/projects/libpcap/ having installed http://www.winpcap.org/ on Windows. Tutorials for using libpcap are around and you'd need to learn to filter out everything but http/https traffic, although once you've got to that stage it shouldn't be too hard. Try http://yuba.stanford.edu/~casado/pcap/section1.html for starters or http://systhread.net/texts/200805lpcap1.php. Both tutorials look reasonable.
I also feel I should point out that "transparent to the user" and "dll" are not equivalent ideas. A DLL is a set of library functions separate from an application that can be used by many applications - see http://en.wikipedia.org/wiki/Dynamic-link_library. A "standard" executable file (i.e. file ending in .exe) can still be transparent to the user if run, for example, as a Windows Service, which might be more what you are looking for.