Socket.IO, I'm either over-thinking it, or I just don't understand how it works. Probably the latter.
Can someone please help me out.
I am seeing examples all over the place that talk about emitting , back to the sender, broadcasting to all clients, or broadcasting to all clients but the sender.
What is not clear is where this is all happening, server or client, or both?
My main questions are:
Does a server have to relay everything to all clients?
Can a client
send a message directly to all other clients (without the server
having to relay it)
Can a client send a message directly to specific
client?
I would be very very grateful for any help in clarifying this to me.
The server does not have to relay everything to the clients. That is where you have the option to emit back to the sender, all clients, or all clients but the sender.
No, the client always sends a message to the server.
No, same reason as above -- you could send a message from original client, to server, to intended specific client, but you would have to hop through the server.
Related
In HTTP, you can tell the client who asks for example.com/foo/ that it should ask for something.else/instead.
Is there a way to do it in SMTP? That is, if the client sends a message to john#example.com, tell it to send it to jane#somewhere.else instead.
I know that I can receive the message and relay it to jane#somewhere.else. For many reasons I don't want to relay messages via my server. Instead, I want to tell the client that it should send it to another address.
The reasons include:
I cannot notify the client of a failure (well, perhaps this can be done).
My server will be blacklisted if the message was spam.
The destination server will consult blacklists with my IP and not with the original sender's IP, etc.
My motivation is:
If this were possible, perhaps it would be a better antispam measure than greylisting.
My institutional server has no antispam filters, while my personal server uses IP-based blacklists such as Spamcop. After the institutional server has received a message, I can scan the message at the client but it's too late to consult Spamcomp and to inform the sender that the message was filtered out (I consider it a must in any filtering). I wish the institutional server could simply redirect people to my personal server, which is a lot better protected and correctly informs the sender of the problem at the SMTP stage.
Sendmail provides FEATURE(redirect) to handle such cases.
It rejects recipient in reply to RCPT TO: with
551 5.1.1 User has moved; please try <newemail#example.com>
Your email server refuses to accept the recipient with hint, it is up to sending host to generate bounce message to the sender. Spammers may/will get the new email too. I do not know any email servers handling automatically such redirects.
I have not investigated how well it is handled by various email clients and level of details provided in bounce message by various email servers.
I'm creating a web XMPP client to connect to an XMPP ejabberd server and I have the following problem:
My client can send messages just alright.
The problem is when I try to receive messages. I only receive stanzas directed to my full JID, that is including the resource I am using, so I don't receive stanzas directed to my user#domain but I do receive stanzas sent to my user#domain/resource.
This is not an ideal situation since the other clients I need to communicate with work with bare JIDs.
I have little experience with Strophe so maybe someone with more experience can illustrate what I'm doing wrong. Thanks in advance!
Have you checked if your xmpp server offers a setting to route messages to all resources?
OpenFire offers a property named route.all-resources which will forward messages to all resources for a person.
Also, you may want to adjust the priority of your resource, as only the resource with the highest priority will have the message sent to it (if the message does not specify a resource).
Here is an example of setting your resource priority to 10 with Strophe.js
connection.send($pres().c("priority").t("10"));
This article describes the intended behaviour, and also this answer from a related question may help you understand what's happening.
I am working on a research project that has to do with responding to spam. I want to implement the following functionality:
1. A mail server that saves all incoming email messages in an easily accessable form - hard drive, database, etc. For example, if someone sends a message to peter#domain.com or akjfhasfkjf#domain.com, this message should be accepted and saved.
2. I should be able to reply to these messages from the same server/account. E.g. a message gets delivered to peter#domain.com, so the spammer receives a response from the same address.
Any suggestions on any software / packages that can help me with that? If I can interface with them with Java or Python, it would be even better.
Thanks.
you could run a postfix mailserver with fuglu,a python framework for mail filters. it would be very simple to write a plugin that does what you want.
but remember: responding to spam is in most cases a bad idea. the sender address is almost always forged, so the reply goes some innocent victim instead of the spammers inbox and your server could be blacklisted for backscattering.
I don't know enough about SIP. As far as I know SIP can not be used in LAN. But it's features are very good. I want to use it for a LAN messenger (with video conference facilities).
Is there any way of using SIP in LAN network ?
The SIP protocol can be used over any reliable transport (TCP, XMPP, instant messaging channel, etc...) to a service (e.g. a server such as a SIP proxy) that knows how to route the SIP INVITE message from the caller to the callee. e.g. If you send an INVITE to bob#foobar.com, there's needs to be a service that knows how to find "bob" and deliver the message. Likewise, when Bob sends back his response messages back, the messages need to route back to the caller who sent the original INVITE.
And you can do SIP without a server - provided the computer already have a connection (direct or indirect) to the other computer intended for the call.
But SIP isn't anything special. If you were to invent your own video conferencing protocol, it would probably look a lot like SIP. SIP's primary job is for both sides of a call to exchange IP/port candidates for connecting directly in addition to codec and bandwidth negotiation data.
After the SIP messages are exchanged, ICE/STUN/TURN take over and RTP packets typically flow. SIP isn't used in the call except to end the call.
What are you really trying to do anyway?
Thread is Old but still I would like to contribute to this. There are various SIP server like http://www.officesip.com/index.html which works in LAN and can be connected to hardware phone too and soft client also.
Jitsi is open source cross platform SIP/xmpp client:https://jitsi.org/
And if you want to XMPP server Openfire is the best:http://www.igniterealtime.org/projects/openfire/
I hope this will definitely help someone..!
I am basically writing a XMPP client to automatically reply to "specific" chat messages.
My setup is like this:
I have pidgin running on my machine configured to run with an account x#xyz.com.
I have my own jabber client configured to run with the same account x#xyz.com.
There could be other XMPP clients .
Here is my requirement:
I am trying to automate certain kind of messages that I receive on gtalk. So whenever I receive a specific message eg: "How are you" , my own XMPP client should reply automatically with say "fine". How are you". All messages sent (before and after my client replies) to x#xyz.com but should be received by all clients (my own client does not have a UI and can only respond to specific messages.).
Now I have already coded my client to reply automatically. This works fine. But the problem I am facing is that as soon as I reply (I use the smack library), all subsequent messages that are sent to x#xyz.com are received only by my XMPP client. This is obviously a problem as my own client is quite dump and does not have a UI, so I don't get to see the rest of the messages sent to me, thereby making me "lose" messages.
I have observed the same behavior with other XMPP clients as well. Now the question is, is this is a requirement of XMPP (I am sorry but I haven't read XMPP protocol too well). Is it possible to code an XMPP client to send a reply to a user and still be able to receive all subsequent messages in all clients currently listening for messages? Making my client a full fledged XMPP client is a solution, but I don't want to go that route.
I hope my question is clear.
You may have to set a negative presence priority for your bot..
First thing to know is that in XMPP protocol every client is supposed to have a full JID. This is a bare JID - in your case x#xyz.com with a resource in the end e.g. x#xyz.com/pidgin or x#xyz.com/home (where /pidgin and /home are the resource). This is a part of how routing messages to different clients is supposed to be achieved.
Then there are the presence stanzas. When going online a client usually sends a presence stanza to the server. This informs about e.g. if the client is available for chat or away for lunch. Along with this information can be sent a priority. When there are more than one clients connected the one with the highest priority will receive the messages sent to the bare JID (e.g. ClientA(prio=50) and ClientB(prio=60) -> ClientB receives the messages sent to x#xyz.com). But there are also negative priorities. A priority less than 0 states that this client should never be sent any messages. Such a stanza might look like this
<presence from="x#xyz.com/bot">
<priority>-1</priority>
</presence>
This may fit your case. Please keep in mind it also depends on the XMPP server where your account is located, which may or may have not fully implemented this part of the protocol.
So to summarize: I recommend you to look through the Smack API how to set a presence and set the priority to <0 for your bot client right after it connected.