Files
mesh-delivery/modules/mesh-delivery-view/vendor/github.com/nats-io/nats.go/netchan.go
T
jschoubben 0dbe8f9a32 Derive the delivery view's rows from the have, assignments and builds buckets (issue 1134)
The operator sees per module and node what is assigned, what the node reports and what it waits on; a have with no open assignment is left behind, never running.
2026-10-18 19:31:50 +02:00

118 lines
3.7 KiB
Go

// Copyright 2013-2023 The NATS Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package nats
import (
"errors"
"reflect"
)
// This allows the functionality for network channels by binding send and receive Go chans
// to subjects and optionally queue groups.
// Data will be encoded and decoded via the EncodedConn and its associated encoders.
// BindSendChan binds a channel for send operations to NATS.
//
// Deprecated: Encoded connections are no longer supported.
func (c *EncodedConn) BindSendChan(subject string, channel any) error {
chVal := reflect.ValueOf(channel)
if chVal.Kind() != reflect.Chan {
return ErrChanArg
}
go chPublish(c, chVal, subject)
return nil
}
// Publish all values that arrive on the channel until it is closed or we
// encounter an error.
func chPublish(c *EncodedConn, chVal reflect.Value, subject string) {
for {
val, ok := chVal.Recv()
if !ok {
// Channel has most likely been closed.
return
}
if e := c.Publish(subject, val.Interface()); e != nil {
// Do this under lock.
c.Conn.mu.Lock()
defer c.Conn.mu.Unlock()
if c.Conn.Opts.AsyncErrorCB != nil {
// FIXME(dlc) - Not sure this is the right thing to do.
// FIXME(ivan) - If the connection is not yet closed, try to schedule the callback
if c.Conn.isClosed() {
go c.Conn.Opts.AsyncErrorCB(c.Conn, nil, e)
} else {
c.Conn.ach.push(func() { c.Conn.Opts.AsyncErrorCB(c.Conn, nil, e) })
}
}
return
}
}
}
// BindRecvChan binds a channel for receive operations from NATS.
//
// Deprecated: Encoded connections are no longer supported.
func (c *EncodedConn) BindRecvChan(subject string, channel any) (*Subscription, error) {
return c.bindRecvChan(subject, _EMPTY_, channel)
}
// BindRecvQueueChan binds a channel for queue-based receive operations from NATS.
//
// Deprecated: Encoded connections are no longer supported.
func (c *EncodedConn) BindRecvQueueChan(subject, queue string, channel any) (*Subscription, error) {
return c.bindRecvChan(subject, queue, channel)
}
// Internal function to bind receive operations for a channel.
func (c *EncodedConn) bindRecvChan(subject, queue string, channel any) (*Subscription, error) {
chVal := reflect.ValueOf(channel)
if chVal.Kind() != reflect.Chan {
return nil, ErrChanArg
}
argType := chVal.Type().Elem()
cb := func(m *Msg) {
var oPtr reflect.Value
if argType.Kind() != reflect.Ptr {
oPtr = reflect.New(argType)
} else {
oPtr = reflect.New(argType.Elem())
}
if err := c.Enc.Decode(m.Subject, m.Data, oPtr.Interface()); err != nil {
c.Conn.err = errors.New("nats: Got an error trying to unmarshal: " + err.Error())
if c.Conn.Opts.AsyncErrorCB != nil {
c.Conn.ach.push(func() { c.Conn.Opts.AsyncErrorCB(c.Conn, m.Sub, c.Conn.err) })
}
return
}
if argType.Kind() != reflect.Ptr {
oPtr = reflect.Indirect(oPtr)
}
// This is a bit hacky, but in this instance we may be trying to send to a closed channel.
// and the user does not know when it is safe to close the channel.
defer func() {
// If we have panicked, recover and close the subscription.
if r := recover(); r != nil {
m.Sub.Unsubscribe()
}
}()
// Actually do the send to the channel.
chVal.Send(oPtr)
}
return c.Conn.subscribe(subject, queue, cb, nil, nil, false, nil)
}