In the Java ME platform that I am using I have only SocketConnection class to connect to a distant server. For example I can create a connection to a server socket on the given ip using Connector.open("socket://"+ip+":"+port).
What I want is to implement an HttpConnection that will use http protocol, a url and port 80 as parameters. I imagine it will be something like Connector.open("http://www.google.com:80) to be able to send GET, POST, DELETE, PUT requests to the server afterwards.
Is there a way to get the ip via url address and then connect to this ip using http protocol? Or if it isn't supported by my platform, then I have to stick to using sockets? I know my question can seem a little abstract, so ask if you need any clarifications.
You have to stick to using sockets. If the Java ME platform that you are using have only SocketConnection, a call to Connector.open("http://www.google.com:80") will throw an exception.
Related
Is there a way to curl (or something similar) a phoenix socket?
Let's say my server is running on localhost:4000, and my endpoint has:
defmodule MyApp.Endpoint do
use Phoenix.Endpoint, otp_app: :my_app
socket "/socket", MyApp.UserSocket
I have a UserSocket module with a connect method. What can I run from the command line to connect to this socket?
cURL supports by default long polling. You don't have to add any flags, just hit websocket url but you have to use http(s) not ws(s) protocol in url. Don't forget to add Accept and content type headers as application/json.
There is one drawback. You can't POST message to same connection :) so I guess it is better to use telnet instead and code by hand header to initiate polling so you can send (post) messages from same console. this way you can debug if "socket" is returning ok reply for your client pushes. and what is event better with this approach you can actually use HTTP 101 protocol upgrade to ws(s) :)
Excuse me. I speak poor English.
I am trying to create a network proxy programming with sock5 protocol. But I have no way to learn it, I can't figure out how a proxy programming works especially the followings:
What is the difference and association between socks5 and the Shadowsocks ?
Can I set a the network proxy configure in macOs instead of using swift or oc ?
such as enabling this check button(socks5 proxy) and filling the specific configure using a language instead of swift or oc:
configure
Once I set the option on macOs in the Question 2,what kind of data will the programming get if it listening the network?
e.g. will the macOs automatically forward the all new TCP connections to 127.0.0.1:1086 and automatically make the connections confirm to the socks5 request standard?
If so, why the final processing programming (transmit the datas to the real remote proxy-server) can make a successful connection? Instead of a forever loop(a.programming create a socket to remote proxy-server -> b. macOs automatically forward it to 127.0.0.1:1086 and make the connection confirm to the socks5 request standard -> a.)
Is it called as a proxy-client? or local proxy-server? what is the job of it. Why do I set a proxy address as a local one instead of a direct remote server?
Why when I setting a fake socks5 option in macOs network proxy options, a UDP programming can still work successfully?
If you can UNDERSTAND CHINESE:
Chinese language
The follow answers are based on my own experience and opinion.
1、socks5 is an Internet protocol that exchanges network packets between a client and server through a proxy server. Sockes
while Shadowsocks is a software use this protocol.
2 、Yes,you can. Install a Shaowsocks don't need any
Programming language, actually it like installing a EXE file on Windows or pkg on MacOS, it's just a software.
3、Socks5 is an Internet protocol like a language between two computer.
The software's message run on you computer will be "translated" by Shadowsocks.
Those translated message will be sent to the remote service (also run a Shadowsocks) then the service can send message to those "blocked" Webs' services.
4、The remote service can be called an proxy service.The local don't do anything except be "translated" by Shadowsocks. Look this picture.
5、The QQ don't use the port 1080, Shadowsocks need a fixed port to "translate" message.
I noticed with Postgres and other databases, the database itself runs a local version of a server.
For example, mine is running on localhost:5432.
Curiously, I went to my web browser and tried typing in that address to see what I'd get, but I got a response that "This Web Page is Not Available".
I also tried things like localhost:5432/mydata but also to no avail.
Shouldn't I be able to see something if I visit the database through my web browser? If yes, how do you do it? If not, why not?
Postgres is a service running on a port. A web server is also a service running on a port (80 and/or 443 usually). There are a lot of things running on various ports on any server, heck, on any single computer. That doesn't mean that everything is interchangeable. Ports 80 and 443 are commonly agreed to serve HTTP(S) connections. HTTP is a specific protocol which specifies how two things can communicate on a specific port. Postgres is not speaking HTTP; you need to speak Postgres' particular protocol if you want to talk to it. The browser does not speak that protocol, and Postgres doesn't by default offer communication in any protocol a browser understands.
A web browser expects to "talk" to servers using a protocol it supports. Webbrowsers support obviously http. Some do support other protocols, like ftp. But your postgres does not speak http. So you don't see anything. The port number is just telling over which channel the server is accessible. Any protocol can be routed over any port, but usually http can be reached over port 80. Your postgress over port 5432.
I want to create a XMPP server on my network and then send message to it with python so that this server can restart the target computer on the network , now how can i set up this server and how can i do the rest of the process?
tnx
I am not sure in what context you are trying to do this, but XMPP has been used in context outside of usual chat and instant messengers (e.g. load balancers, rpc, ...).
There can be several ways of doing this. One way I can think right now is by using Jabber RPC xep-0009 which says:
This specification defines an XMPP protocol extension for
transporting XML-RPC encoded requests and responses between two XMPP entities.
The protocol supports all syntax and semantics of XML-RPC except that
it uses XMPP instead of HTTP as the underlying transport.
Workflow wise here is how you can make this work:
You will need a jabber server which is up and running say on host-A
You will need to configure a startup service on other hosts in the network (say on host-B, host-C, host-D). This startup service is nothing but a xmpp client daemon which will start in the background whenever host is started.
This xmpp client configured as startup service are special in the sense that they will accept incoming rpc calls (support for XEP-0009) and execute received commands on the host.
Received RPC commands can be synonymous to shutdown, kill -9 xxxx depending upon your specific needs.
Finally, xmpp client on host-C can send one or more commands wrapped inside an stanza to xmpp client running on host-B.
You can use one of the existing python xmpp client library and simply extend their working examples for your use case. You will also need to check details on how to configure startup service depending upon your Operating System (e.g. update-rc.d for ubuntu or sc.exe for windows)
I am working with the BlueZ libraries for managing the bluetooth stack under linux. I am trying to open a socket that should connect with a specific service whose UUID is known. I have successfully tried to open sockets between a server and a client following the examples here:
http://people.csail.mit.edu/albert/bluez-intro/c404.html
where it is also described how to explore services in a remote host; however, what I cannot figure out is how to specify the UUID while connecting the socket. This is something quite straightforward on other contexts, as it happens when using Android libraries; however, with BlueZ I haven't found examples on the web.
Thanks for the help!
Stefano
-- added some details in a reply... don't know if it's right or not; if not, sorry
thanks for your help!
In my post I said I wanted to connect a socket with a specified UUID since I had in mind a function like createRfcommSocketToServiceRecord as can be found in:
http://developer.android.com/reference/android/bluetooth/BluetoothDevice.html#createRfcommSocketToServiceRecord%28java.util.UUID%29
which returns a socket given a certain UUID. I am developing two softwares, one being the client and the other the server, therefore it's a service I am creating, not a standard one. I publish such service on the server with a specified UUID, and I would like to connect to it from the client. The server is running fine, since with an android platform, exploiting the mentioned createRfcommSocketToServiceRecord method, I am able to connect to the server with the right service.
The example you posted is very clear as well, but unfortunately it is in Python, while (I forgot to point out) I am using Bluez as a C library. I am able to exploit the SDP and inspect services on a remote server; however, when it is the time of setting up the socket, I don't see how to specify the port. I thought about the rc_channel, but as far as I understood it is the bluetooth channel (ranging from 1 to 11 or something similar). Could you please point out Where I should be able to specify the port while creating the socket in the client? And where am I able to find the right port in the complex structure the sdp is dealing with? -- referred to:
http://people.csail.mit.edu/albert/bluez-intro/x604.html
Thanks again for the help!
You don't connect sockets by UUID. You use a socket to connect to remote device and browse its SDP to discover the UUIDs it offers, and map that to a socket port. Here's an example of this process using PyBluez, python wrappers above BlueZ
http://people.csail.mit.edu/albert/bluez-intro/x290.html