Commit Graph

15 Commits

Author SHA1 Message Date
zhiqiangxu
6f08c2f3f1
rpc: add method to test for subscription support (#25942)
This adds two ways to check for subscription support. First, one can now check
whether the transport method (HTTP/WS/etc.) is capable of subscriptions using
the new Client.SupportsSubscriptions method.

Second, the error returned by Subscribe can now reliably be tested using this
pattern:
    
    sub, err := client.Subscribe(...)
    if errors.Is(err, rpc.ErrNotificationsUnsupported) {
        // no subscription support
    }

---------

Co-authored-by: Felix Lange <fjl@twurst.com>
2023-06-14 14:04:41 +02:00
Sina Mahmoodi
f20eba426a
graphql, node, rpc: improve HTTP write timeout handling (#25457)
Here we add special handling for sending an error response when the write timeout of the
HTTP server is just about to expire. This is surprisingly difficult to get right, since is
must be ensured that all output is fully flushed in time, which needs support from
multiple levels of the RPC handler stack:

The timeout response can't use chunked transfer-encoding because there is no way to write
the final terminating chunk. net/http writes it when the topmost handler returns, but the
timeout will already be over by the time that happens. We decided to disable chunked
encoding by setting content-length explicitly.

Gzip compression must also be disabled for timeout responses because we don't know the
true content-length before compressing all output, i.e. compression would reintroduce
chunked transfer-encoding.
2022-12-07 14:02:14 +01:00
s7v7nislands
f4ff4268f7
rpc: fix godoc (#24488)
Co-authored-by: seven <seven@nodereal.io>
2022-03-02 02:51:55 +01:00
Felix Lange
4a37ae510e
rpc: tighter shutdown synchronization in client subscription (#22597)
This fixes a rare issue where the client subscription forwarding loop
would attempt send on the subscription's channel after Unsubscribe has
returned, leading to a panic if the subscription channel was already
closed by the user. Example:

    sub, _ := client.Subscribe(..., channel, ...)
    sub.Unsubscribe()
    close(channel)

The race occurred because Unsubscribe called quitWithServer to tell the
forwarding loop to stop sending on sub.channel, but did not wait for the
loop to actually come down. This is fixed by adding an additional channel
to track the shutdown, on which Unsubscribe now waits.

Fixes #22322
2021-03-30 20:09:30 +02:00
Felix Lange
9c2ac6fbd5
rpc: remove silly use of ReadVarint in subscription ID generator (#21391)
Found by @protolambda
2020-07-31 16:20:31 +02:00
rene
d7851e6359
graphql, node, rpc: fix typos in comments (#20824) 2020-03-27 13:52:53 +01:00
Felix Lange
8008c5b1fa rpc: remove 'exported or builtin' restriction for parameters (#20332)
* rpc: remove 'exported or builtin' restriction for parameters

There is no technial reason for this restriction because package reflect
can create values of any type. Requiring parameters and return values to
be exported causes a lot of noise in package exports.

* rpc: fix staticcheck warnings
2019-11-20 10:06:21 +02:00
Felix Lange
7c4a4eb58a rpc, p2p/simulations: use github.com/gorilla/websocket (#20289)
* rpc: improve codec abstraction

rpc.ServerCodec is an opaque interface. There was only one way to get a
codec using existing APIs: rpc.NewJSONCodec. This change exports
newCodec (as NewFuncCodec) and NewJSONCodec (as NewCodec). It also makes
all codec methods non-public to avoid showing internals in godoc.

While here, remove codec options in tests because they are not
supported anymore.

* p2p/simulations: use github.com/gorilla/websocket

This package was the last remaining user of golang.org/x/net/websocket.
Migrating to the new library wasn't straightforward because it is no
longer possible to treat WebSocket connections as a net.Conn.

* vendor: delete golang.org/x/net/websocket

* rpc: fix godoc comments and run gofmt
2019-11-18 10:40:59 +02:00
Felix Lange
245f3146c2
rpc: implement full bi-directional communication (#18471)
New APIs added:

    client.RegisterName(namespace, service) // makes service available to server
    client.Notify(ctx, method, args...)     // sends a notification
    ClientFromContext(ctx)                  // to get a client in handler method

This is essentially a rewrite of the server-side code. JSON-RPC
processing code is now the same on both server and client side. Many
minor issues were fixed in the process and there is a new test suite for
JSON-RPC spec compliance (and non-compliance in some cases).

List of behavior changes:

- Method handlers are now called with a per-request context instead of a
  per-connection context. The context is canceled right after the method
  returns.
- Subscription error channels are always closed when the connection
  ends. There is no need to also wait on the Notifier's Closed channel
  to detect whether the subscription has ended.
- Client now omits "params" instead of sending "params": null when there
  are no arguments to a call. The previous behavior was not compliant
  with the spec. The server still accepts "params": null.
- Floating point numbers are allowed as "id". The spec doesn't allow
  them, but we handle request "id" as json.RawMessage and guarantee that
  the same number will be sent back.
- Logging is improved significantly. There is now a message at DEBUG
  level for each RPC call served.
2019-02-04 13:47:34 +01:00
Felix Lange
4e474c74dc
rpc: fix subscription corner case and speed up tests (#17874)
Notifier tracks whether subscription are 'active'. A subscription
becomes active when the subscription ID has been sent to the client. If
the client sends notifications in the request handler before the
subscription becomes active they are dropped. The tests tried to work
around this problem by always waiting 5s before sending the first
notification.

Fix it by buffering notifications until the subscription becomes active.
This speeds up all subscription tests.

Also fix TestSubscriptionMultipleNamespaces to wait for three messages
per subscription instead of six. The test now finishes just after all
notifications have been received and doesn't hit the 30s timeout anymore.
2018-10-09 16:34:24 +02:00
Egon Elbre
e063d538b8 rpc: fix megacheck warnings 2017-08-08 11:08:37 +02:00
Bas van Kervel
37e3f561f1
rpc: support subscriptions under custom namespaces 2017-04-25 11:13:22 +02:00
Felix Lange
c213fd1fd8 all: import "context" instead of "golang.org/x/net/context"
There is no need to depend on the old context package now that the
minimum Go version is 1.7. The move to "context" eliminates our weird
vendoring setup. Some vendored code still uses golang.org/x/net/context
and it is now vendored in the normal way.

This change triggered new vet checks around context.WithTimeout which
didn't fire with golang.org/x/net/context.
2017-03-22 20:49:15 +01:00
Péter Szilágyi
18c77744ff
all: fix spelling errors 2017-01-06 19:44:35 +02:00
Bas van Kervel
47ff813012 rpc: refactor subscriptions and filters 2016-08-17 12:59:58 +02:00