is it possibile to set the maximum number of sockets that my server can handle? Something like: maxSocket = 2 and from the 3 attempt of a socket to connect automatically refuse that connection?
Thanks
The default maxSockets value is Infinity and it determines the limit of number of sockets per host. See official docs: https://nodejs.org/api/http.html#http_agent_maxsockets
You can manually set maxSockets limit using the following code snippet
require('http').globalAgent.maxSockets = 10
globalAgent: Global instance of Agent which is used as the default for all HTTP client requests.
In Node.js, you can set the maximum number of connections per origin.
If maxSockets is set, the low-level HTTP client queues requests and
assigns them to sockets as they become available.
Ref URL from AWS JS SDK
According to Node.js Doc,
By default set to Infinity. Determines how many concurrent sockets the
agent can have open per origin. Origin is either a 'host:port' or
'host:port:localAddress' combination.
Conventionally, they recommend 25~50, I guess.
Related
I have 2 devices (desktop PCs), each running a browser tab that instantiates an IPFS node using js-ipfs.
//file index.html, served over HTTPS
const node = IpfsCore.create(); //ipfs browser node
Both nodes have peers (calling node.swarm.addrs() returns about 50 peers). They do not list each other as peers.
I want to connect those two nodes to each other, so if I call node.add( ... ) on the first, I can then call node.cat( ... ) on the second, and acquire a file from the first. (Or so that browser 1's pubsub broadcasts always reach browser 2; browser 1 can read browser 2's wantlist etc.)
How do I connect these 2 browser tabs as peers?
The example at https://github.com/ipfs/js-ipfs/blob/master/packages/interface-ipfs-core/src/swarm/connect.js uses this command:
ipfsA.swarm.connect( ipfsBId.addresses[0] )
But in my case, both my browser-tabs have no addresses.
console.log( ( await node.id() ).addresses ); //[] empty array
I don't know how the browser tabs manage connecting to other peers without their own addresses, and I don't know how to make them connect to each other.
There is a 4-year-old question about browser peers here IPFS - pubsub connect to peers from browser, but its fairly unrelated and seems to rely on the the deprecated / out-of-date webrtc-star https://github.com/libp2p/js-libp2p-webrtc-star
I know if I were setting up a WebRTC connection I would use fetch() or XHR or a websocket to a public-facing server (with a DNS record or IP address) to exchange negotiation info while querying a list of iceServers (also with DNS records / IP addresses).
I don't want to rely on a list of servers I own or configure, and I don't want to burden any public example TURN servers or anything. js-libp2p might use multicastDNS? I don't think browser tabs can broadcast signals though (I could be wrong? Maybe fetch() can do that somehow with some sneaky url stuff?)
What do I do? How can these two browser-tab IPFS peers discover each other, specifically?
I suspect this has a very straight-forward answer, but I have been researching for days now and read hundreds of pages, and none of the documentation I have read anywhere is relevant. Wherever the answer is on this vast Internet, I have not been able to find it.
Is it possible to establish a WebRTC connection between two browsers on a local area network without calling createOffer/Answer and instead by manually creating local and remote descriptions?
The browsers are not behind NAT with respect to each other and they have signaled their IP addresses somehow (say via a local HTTP server).
Would it be possible to do something in the spirit of:
const myIp = '192.168.0.1';
const peerIp = '192.168.0.2';
const c = new RTCPeerConnection();
c.setLocalDescription(MAGIC_createLocalDescriptionFor(myIp));
c.setRemoteDescription(MAGIC_createRemoteDescriptionFor(peerIp));
Yes! If you are using Chrome. Check out offline-browser-communication
You have three points of state you need to deal with.
IP/Port. You can setup your network in a way that this is stable. Or attempt to do some guessing?
ufrag/pwd. You can set this via SetLocalDescription so you can control these.
DTLS Certificate. Use GenerateCertificate this means you will only have to signal it once.
Not in the browser. The offer and answer contain properties such as ice-ufrag, ice-pwd, the DTLS fingerprints and the candidate ports etc that are not static.
I have a simple socket.io client and server program, running on node.js. The client and server exchange messages between them for a few minutes, before disconnecting (like chat).
If there any function/method I can use to get the total bytes transferred (read/write), after the socket is closed?
At present I am adding up the message size for each each message sent and received by the client. But, as per my understanding, in socket.io depending on which protocol is used (websocket, xhr-polling, etc.), the size of the final payload being sent will differ due to the header/wrapper size. Hence, just adding message bytes won't give me an accurate measure of bytes transferred.
I can use monitoring tools like Wireshark to get this value, but I would prefer using a javascript utility to get this value. Search online, didn't give me any reasonable answer.
For pure websocket connections, I am being able to get this value using the functions: socket._socket.bytesRead and socket._socket.bytesWritten
Any help is appreciated!
As of socket v2.2.0 i managed to get byte data like this. Only problem these are specified when client closes browser window and reason parameter is transport error. If client uses socket.close() or .disconnect() or server uses .disconnect() then bytes are 0.
socket.on('disconnect', (reason) => {
let symbs = Object.getOwnPropertySymbols(socket.conn.transport.socket._socket);
let bytesRead = socket.conn.transport.socket._socket[symbs[3]];
let bytesWritten = socket.conn.transport.socket._socket[symbs[4]];
});
If you wanted such a feature that would work no matter what the underlying transport was below a socket.io connection, then this would have to be a fundamental feature of socket.io because only it knows the details of what it's doing with each transport and protocol.
But, socket.io does not have this feature built in for the various transports that it could use. I would conclude that if you're going to use the socket.io interface to abstract out the specific protocol and implementation on top of that protocol, then you give up the ability to know exactly how many bytes socket.io chooses to use in order to implement the connection on its chosen transport.
There are likely debug APIs (probably only available to browser extensions, not standard web pages) that can give you access to some of the page-wide info you see in the Chrome debugger so that might be an option to investigate. See the info for chrome.devtools.network if you want more info.
Maximum HTTP Request execution time is 120sec in Node.js , how can i increase max execution time on http get/post requests?
NOTE:I'm using expressjs framework
http://nodejs.org/api/http.html#http_server_timeout
server.timeout
Number Default = 120000 (2 minutes)
The number of milliseconds of inactivity before a socket is presumed to have timed out.
Note that the socket timeout logic is set up on connection, so changing this value only affects new connections to the server, not any existing connections.
Set to 0 to disable any kind of automatic timeout behavior on incoming connections.
You would use server.setTimeout(0); to get what you're after. It's documented here. Although I can't figure out why you would need to change this except for troubleshooting.
Is there a way to modify the Node.js maxSockets setting when using the Express framework?
Somewhere after you do var http = require('http'), just add http.globalAgent.maxSockets = x (where 'x' is the number of sockets you want).
Please note that if you are making requests over https, you will need to set maxSockets for https as well.
var https = require('https');
https.globalAgent.maxSockets = your_val_here;
From version v0.12.0 maxSockets set to Infinity
maxSockets are no longer limited to 5. The default is now set to Infinity with the developer and the operating system given control over how many simultaneous connections an application can keep open to a given host.
Node v0.12.0 (Stable) release notes