WebSockets - send json data via php

Question

I\'m trying to send a fire-and-forget request from PHP to my websocket aws api gateway.

I\'ve set up an action called \"sendmessage\".

This is the code I\'m

Answer 1

Since you didn't provide a handpoint link, here is some notes, following own tests!

I guess the issue comes from the wss part, php needs to retrieve the certificate first, so it can encrypt the data.

Your code should work just fine on a ws:// stream.

To connect to a regular ws:// stream, one can simply use fsockopen().

\n";
} else {
    fwrite($fp, "\n");
    echo "Connected!";
    echo fread($fp, 26);
    fclose($fp);
}

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But to connect to a wss:// secure websocket stream, using php, without libraries, we need to create a tunnel first, by querying the public key with stream_socket_client.

This is a handshake mechanism. This can be done as follow.

Notice the first ssl:// call. This is the TLS 1.0 protocol.

The output should looks like:

string(44) "HTTP/1.1 101 Web Socket Protocol Handshake"
string(21) "Connection: Upgrade"
string(37) "Date: Thu, 12 Dec 2019 04:06:27 GMT"
string(52) "Sec-WebSocket-Accept: fTYwcEa6D9kJBtghptkz1e9CtBI="
string(25) "Server: Kaazing Gateway"
string(20) "Upgrade: websocket"

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Same base code, another example, pulling data from Binance wss:// stream.

We can also use TLS 1.2, with a tls:// handshake instead. Works on most servers.

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Here is a way to retrieve only the ssl RSA public key of a remote handpoint, from php. Can be used to speed up later connections.

 true,
  "capture_peer_cert_chain" => true
];
$a = stream_context_create(["ssl"=>$opt]);
$b = stream_socket_client("ssl://stream.binance.com:9443", $errno, $errstr, 30, STREAM_CLIENT_CONNECT, $a);
$cont = stream_context_get_params($b);
$key = openssl_pkey_get_public($cont["options"]["ssl"]["peer_certificate"]);
$c = openssl_pkey_get_details($key);
var_dump($c["key"]);

Output something like:

-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhki(...)7aEsFtUNkwM5R5b1mpqzAwqHyvdamJx20bT6SS6
PYXSr/dv8ak1d4e2Q0nIa1O7l3w0bZZ4wnp5B8Z+tjPd1W8uaZoRO2iVkPMh2yPl
j0mmtUw1YlfDyutH/t4FlRCDiD4JjdREQGs381/+jbkdjl2SIb1IyNiCdAXA6zsq
xwIDAQAB
-----END PUBLIC KEY-----

There is possibly other quircks, to be sure, we need the main handpoint^. Would be glad to test that. Otherwise good luck, there is a big lack of documentation on the subject.

This is still a new born protocol (2011!). Best details are in the RFC specification:

The WebSocket protocol was standardized by the IETF as RFC 6455 in 2011

About the handshake, it must be initiated by a GET request.

The client will send a pretty standard HTTP request with headers that looks like this (the HTTP version must be 1.1 or greater, and the method must be GET)

Writing_WebSocket_servers#Client_handshake_request

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In short:

If unencrypted WebSocket traffic flows through an explicit or a transparent proxy server without WebSockets support, the connection will likely fail.

WebSocket#Proxy_traversal

Transport_Layer_Security#Digital_certificates