The v3 parser (used for compatibility with older clients) was broken
during the migration to TypeScript ([1]).
This was not caught in the test suite because the Node.js client does
not support binary packet in polling mode (packets are base64-encoded).
[1]: c0d6eaa1ba
Backported from 6.0.x branch: 3f42262fd2
This should fix the following error:
> TypeError: Cannot read property 'writeHead' of undefined
This bug was introduced by [1], because the `if (res !== undefined) { ... }`
check was removed.
But `res` is indeed undefined when the client connects with WebSocket
directly, in that case we need to manually write the response content
(in the abortUpgrade method).
Please note that the previous behavior was invalid too, since the
WebSocket connection was left open when an error occurred during the
handshake.
[1]: 7096e98a02
This option will be used when broadcasting a packet to multiple clients,
in order to only encode the packet once.
Usage:
```js
socket.write("test", {
wsPreEncoded: "4test"
});
```
Note: pre-encoding the content with HTTP long-polling is a bit harder,
since the concatenation of the packets is specific to each client.
This change should reduce memory usage when many packets are emitted to
many clients in a burst.
Co-authored-by: Branislav Katreniak <bkatreniak@slido.com>
Those events will be emitted before the response headers are written to
the socket:
- "initial_headers": on the first request of the connection
- "headers": on all requests (HTTP long-polling and WebSocket upgrade)
Syntax:
```js
server.on("initial_headers", (headers, req) => {
headers["test"] = "123";
headers["set-cookie"] = "mycookie=456";
});
server.on("headers", (headers, req) => {
headers["test"] = "789";
});
```
Related:
- https://github.com/socketio/engine.io/issues/557
- https://github.com/socketio/socket.io/issues/3630
The "connection_error" event will be emitted when one of the following
errors occurs:
- Transport unknown
- Session ID unknown
- Bad handshake method
- Bad request
- Forbidden
- Unsupported protocol version
Syntax:
```js
server.on("connection_error", (err) => {
console.log(err.req); // the request object
console.log(err.code); // the error code, for example 1
console.log(err.message); // the error message, for example "Session ID unknown"
console.log(err.context); // some additional error context
});
```
Related:
- https://github.com/socketio/socket.io/issues/3819
- https://github.com/socketio/engine.io/issues/576
This change is necessary to get rid of:
> Critical dependency: the request of a dependency is an expression
when bundling the server with webpack.
BREAKING CHANGE: the syntax of the "wsEngine" option is updated
Before:
```js
const eioServer = require("engine.io")(httpServer, {
wsEngine: "eiows"
});
```
After:
```js
const eioServer = require("engine.io")(httpServer, {
wsEngine: require("eiows").Server
});
```
Related: https://github.com/socketio/engine.io/issues/609
socket.io-client-swift libs version <=15.2.0, which uses protocol
version 3, do not explicitly add the EIO query parameter at transport
initialization. This omission leads the server to treat the client as
a client that supports the protocol version 4, previously set as
default, which is not correct for those versions of the client lib.
From socket.io-client-swift version v16.0.0 the EIO query parameter is
explicitly passed to specify the protocol version supported, but since
the allowEIO3 parameter aims to make the server compatible with
previous versions which in most of the cases are already used in
production and not easily upgradable, it makes more sense to default
the EIO version to 3 if not explicitly set by the client since the
newer client versions pass the EIO protocol version in query
parameters.
Related: https://github.com/socketio/socket.io/issues/3794
This value was updated from 60000 to 5000 in [1], included in
`engine.io@3.2.0` (Feb 2018).
The reasoning back then:
Some users experienced long delays between disconnection on the
server-side and on the client-side. The "disconnect" event would take a
long time to fire in the browser, probably due to a timer being
delayed. Hence the change.
That being said, the current value (5s) now causes unexpected
disconnections when a big payload is sent over a slow network, because
it prevents the ping-pong packets from being exchanged between the
client and the server. This can also happen when a synchronous task
blocks the server for more than 5 seconds.
The new value (20s) thus seems like a good balance between quick
disconnection detection and tolerance to various delays.
Note: pingInterval + pingTimeout is still below the threshold of React
Native, which complains if a timer is set with a delay of more than 1
minute.
[1]: 65b1ad1b8a
Related:
- https://github.com/socketio/socket.io/issues/2770
- https://github.com/socketio/socket.io/issues/2769
- https://github.com/socketio/socket.io/issues/3054
- https://github.com/socketio/socket.io/issues/3376
There was two issues with this behavior:
- v3 clients (with allowEIO3: true) were also receiving a "ping" after
a successful upgrade, which is incorrect (in v3, it's the client that
sends the "ping", and the server answers with a "pong")
- the ping timer is not reset after upgrade on the client-side, so an
upgrade which took longer than the `pingTimeout` duration could lead to
a "ping timeout" error on the client-side
I think the latter issue is present since the initial implementation.
Related: https://github.com/socketio/socket.io-client-swift/pull/1309#issuecomment-768475704
The `main` entry for the `package.json` file is for defining the entry
point. The entry is currently missing the required `.js` extension,
this PR brings it back.
