We have an embedded Apache FTP server running in a gateway for several years. It always worked without problems.
But now a customer is trying to connect with a device of a brand that we've never had before, and contrary to all other clients so far, that thing sends the ALLO command in advance to make sure the server has enough space.
But Apache FTP doesn't seem to know that command. the trace log states:
RECEIVED: ALLO 77482
SENT: 502 Command ALLO not implemented.
following which the client cuts the connection.
The command is also not present in the Apache documentation:
https://mina.apache.org/ftpserver-project/ftpserver_commands.html
So the question is, can I plug my own implementation into the server somehow?
Just to be clear, I'm not asking how to implement the functionality. Just how I can pass my own implementation to Apache FTP for use. If that is possible without touching the source code.
Since the application in question has been running very stable for a long time, I would really hate to tear the Apache FTP server out of there and embed another one...
Well, that was surprisingly simple once I dug myself through to the right code.
The implementation of a command is simple enough, in this case I've just started with a stub for testing:
class ALLO : AbstractCommand() {
override fun execute(session: FtpIoSession, context: FtpServerContext, request: FtpRequest) {
session.write(LocalizedFtpReply.translate(session, request, context,
FtpReply.REPLY_200_COMMAND_OKAY, "ALLO", "bring it!"))
}
}
Inherit AbstractCommand, override execute and write a response to the session.
The question is of course then how to make the server aware of the implementation, which also turns out to be really simple, although there sure as hell doesn't seem to be any documentation around. But you can just instantiate a CommandFactoryFactory, map your implementation, build the CommandFactory and set it in the FtpServerFactory:
val commandFactoryFactory = CommandFactoryFactory()
commandFactoryFactory.addCommand("ALLO", ALLO())
serverFactory.commandFactory = commandFactoryFactory.createCommandFactory()
Related
How do I make an actual remote call?
I've followed the guide: https://codelabs.developers.google.com/codelabs/webrtc-web/#4
And gotten their example fully integrated in my application (Angular, TypeScript, multi webcam &etc).
How do I make the remote call actually remote? - I get the idea of a signalling server, but maybe someone can show with basic strings?
I found this, but it's not been updated in a while so I'm not sure what's still valid:
Found some nice sequence diagrams https://webrtc.org/native-code/native-apis/
Setup call
(source: webrtc.org)
Receive a Call
(source: webrtc.org)
Close Down a Call
(source: webrtc.org)
I have developing Forge Minecraft mods for some time now. I was wondering if it were possible to actually put them on a server. I can't seem to find a direct answer. I know that this may not be the place to put this but I am just dying to know. Please let me know if I can do it, and if so, how.
You can't turn a MC mod into a server plugin because Bukkit and Forge are different things (take it from a plugin dev); however, you can make a mod work on Forge servers.
When making a Forge server, all of your server's players will have to have the client mod, in addition to the Forge client, installed for it to work, so be prepared.
The first step is to actually install the server. Next, go to your Forge server folder, and upload the mod(s) into the folder. Then restart your server and boom, its there. Server mods can be found here.
So if you didn't want to read this, the gist of it is, no, you cannot, but your mods can be used on a Forge server, but not as plugins for a Bukkit or Spigot server, and that your players will need a clientside modpack. Hope this helped!
If you want to make your mod server side only, without having your "clients" having to download it, add acceptableRemoteVersions = "*" to your #Mod line.
This way players don't have to have the mod to be able to connect to the server. This way you can have plugins/mods like dynmap or whotookmycookies without the players having to have the mod as well.
If you want to put them on a server, yes you can. But keep in mind if you solely developped for single player worlds you'll run into "Side" issues.
Code will break beacuse some code is specifically Client side only, and some code is Server side only.
You will have to adapt some synching code with packets to make sure all your graphical things will happen and user input will be returned to you.
Single player worlds are way less picky in that aspect. So make sure you run all your code on the "proper" side, and remember if(!world.isRemote)(test to see if you are running serverside) is your friend.
#Mod(modid = MyMod.MODID, name = MyMod.NAME, version = MyMod.VERSION), acceptableRemoteVersions = "*"
public class MyMod {
....
}
I'm using Netty to write a client application that sends UDP messages to a server. In short I'm using this piece of code to write the stream to the channel:
ChannelFuture future = channel.write(request, remoteInetSocketAddress);
future.awaitUninterruptibly(timeout);
if(!future.isDone()){
//abort logic
}
Everything works fine, but one thing: I'm unable to test the abort logic as I cannot make the write to fail - i.e. even if the server is down the future would be completed successfully. The write operation usually takes about 1 ms so setting very little timeout doesn't help too much.
I know the preffered way would be to use an asynch model instead of await() call, however for my scenario I need it to be synchronous and I need to be sure it get finnished at some point.
Does anyone know how could I simulate an uncompleted future?
Many thanks in advance!
MM
Depending on how your code is written you could use a mock framework such as mockito. If that is not possible, you can also use a "connected" UDP socket, i.e. a datagram socket that is bound to a local address. If you send to a bogus server you should get PortunreachableException or something similar.
Netty has a class FailedFuture that can be used for the purpose of this,
You can for example mock your class with tests that simulate the following:
ChannelFuture future;
if(ALWAYS_FAIL) {
future = channel.newFailedFuture(new Exception("I failed"));
else
future = channel.write(request, remoteInetSocketAddress);
I get the following error within Magento CE 1.6.1.0
Warning: session_start() [<a href='function.session-start'>function.session-start</a>]: Cannot send session cookie - headers already sent by (output started at /home/dev/env/var/www/user/dev/wdcastaging/lib/Zend/Controller/Response/Abstract.php:586) in /home/dev/env/var/www/user/dev/wdcastaging/app/code/core/Mage/Core/Model/Session/Abstract/Varien.php on line 119
when accessing /api/soap/?wsdl
Apparently, a session_start() is being attempted after the entire contents of the WSDL file have already been output, resulting in the error.
Why is magento attempting to start a session after outputting all the datums? I'm glad you asked. So it looks like controller_front_send_response_after is being hooked by Mage_Persistent in order to call synchronizePersistentInfo(), which in turn ends up getting that session_start() to fire.
The interesting thing is that this wasn't always happening, initially the WSDL loaded just fine for me, initially I racked my brains to try and see what customization may have been made to our install to cause this, but the tracing I've done seems to indicate that this is all happening entirely inside of core.
We have also experienced a tiny bit of (completely unrelated) strangeness with Mage_Persistent which makes me a little more willing to throw my hands up at this point and SO it.
I've done a bit of searching on SO and have found some questions related to the whole "headers already sent" thing in general, but not this specific case.
Any thoughts?
Oh, and the temporary workaround I have in place is simply disabling Mage_Persistent via the persistent/options/enable config data. I also did a little bit of digging as to whether it might be possible to observe an event in order to disable this module only for the WSDL controller (since that seems to be the only one having problems), but it looks like that module relies exclusively on this config flag to determine it's enabled status.
UPDATE: Bug has been reported: http://www.magentocommerce.com/bug-tracking/issue?issue=13370
I'd report this is a bug to the Magento team. The Magento API controllers all route through standard Magento action controller objects, and all these objects inherit from the Mage_Api_Controller_Action class. This class has a preDispatch method
class Mage_Api_Controller_Action extends Mage_Core_Controller_Front_Action
{
public function preDispatch()
{
$this->getLayout()->setArea('adminhtml');
Mage::app()->setCurrentStore('admin');
$this->setFlag('', self::FLAG_NO_START_SESSION, 1); // Do not start standart session
parent::preDispatch();
return $this;
}
//...
}
which includes setting a flag to ensure normal session handling doesn't start for API methods.
$this->setFlag('', self::FLAG_NO_START_SESSION, 1);
So, it sounds like there's code in synchronizePersistentInf that assumes the existence of a session object, and when it uses it the session is initialized, resulting in the error you've seen. Normally, this isn't a problem as every other controller has initialized a session at this point, but the API controllers explicitly turns it off.
As far as fixes go, your best bet (and probably the quick answer you'll get from Magento support) will be to disable the persistant cart feature for the default configuration setting, but then enable it for specific stores that need it. This will let carts
Coming up with a fix on your own is going to be uncharted territory, and I can't think of a way to do it that isn't terribly hacky/unstable. The most straight forward way would be a class rewrite on the synchronizePersistentInf that calls it's parent method unless you've detected this is an API request.
This answer is not meant to replace the existing answer. But I wanted to drop some code in here in case someone runs into this issue, and comments don't really allow for code formatting.
I went with a simple local code pool override of Mage_Persistent_Model_Observer_Session to exit out of the function for any URL routes that are within /api/*
Not expecting this fix to need to be very long-lived or upgrade-friendly, b/c I'm expecting them to fix this in the next release or so.
public function synchronizePersistentInfo(Varien_Event_Observer $observer)
{
...
if ($request->getRouteName() == 'api') {
return;
}
...
}
I'm working with node and would like to include a module stored on a remote server in my app.
I.E. I'd like to do something along these lines (which does not work as is):
var remoteMod = require('http:// ... url to my remote module ... ');
As a workaround I'd be happy with just grabbing the contents of the remote file and parsing out what I need if that's easier - though I haven't had much luck with that either. I have a feeling I'm missing something basic here (as I'm a relative beginner with node), but couldn't turn up anything after scouring the docs.
EDIT:
I own both local and remote servers so I'm not concerned with security issues here.
If I'm just going to grab the file contents I'd like to do so this synchronously. Using require('http').get can get me the file, but working from within the callback is not optimal for what I'm trying to do. I'd really be looking for something akin to php's fopen function - if that's even doable with node.
Running code loaded from another server is very dangerous. What if someone can modify this code? This person would be able to run every code he wants on your server.
You can grab remote file just via http
http://nodejs.org/docs/v0.4.6/api/http.html#http.get
require('http').get({host: 'www.example.com', path: '/mystaticfile.txt'}, function(res) {
//do something
});