minio/cmd/grid.go
Klaus Post 51aa59a737
perf: websocket grid connectivity for all internode communication (#18461)
This PR adds a WebSocket grid feature that allows servers to communicate via 
a single two-way connection.

There are two request types:

* Single requests, which are `[]byte => ([]byte, error)`. This is for efficient small
  roundtrips with small payloads.

* Streaming requests which are `[]byte, chan []byte => chan []byte (and error)`,
  which allows for different combinations of full two-way streams with an initial payload.

Only a single stream is created between two machines - and there is, as such, no
server/client relation since both sides can initiate and handle requests. Which server
initiates the request is decided deterministically on the server names.

Requests are made through a mux client and server, which handles message
passing, congestion, cancelation, timeouts, etc.

If a connection is lost, all requests are canceled, and the calling server will try
to reconnect. Registered handlers can operate directly on byte 
slices or use a higher-level generics abstraction.

There is no versioning of handlers/clients, and incompatible changes should
be handled by adding new handlers.

The request path can be changed to a new one for any protocol changes.

First, all servers create a "Manager." The manager must know its address 
as well as all remote addresses. This will manage all connections.
To get a connection to any remote, ask the manager to provide it given
the remote address using.

```
func (m *Manager) Connection(host string) *Connection
```

All serverside handlers must also be registered on the manager. This will
make sure that all incoming requests are served. The number of in-flight 
requests and responses must also be given for streaming requests.

The "Connection" returned manages the mux-clients. Requests issued
to the connection will be sent to the remote.

* `func (c *Connection) Request(ctx context.Context, h HandlerID, req []byte) ([]byte, error)`
   performs a single request and returns the result. Any deadline provided on the request is
   forwarded to the server, and canceling the context will make the function return at once.

* `func (c *Connection) NewStream(ctx context.Context, h HandlerID, payload []byte) (st *Stream, err error)`
   will initiate a remote call and send the initial payload.

```Go
// A Stream is a two-way stream.
// All responses *must* be read by the caller.
// If the call is canceled through the context,
//The appropriate error will be returned.
type Stream struct {
	// Responses from the remote server.
	// Channel will be closed after an error or when the remote closes.
	// All responses *must* be read by the caller until either an error is returned or the channel is closed.
	// Canceling the context will cause the context cancellation error to be returned.
	Responses <-chan Response

	// Requests sent to the server.
	// If the handler is defined with 0 incoming capacity this will be nil.
	// Channel *must* be closed to signal the end of the stream.
	// If the request context is canceled, the stream will no longer process requests.
	Requests chan<- []byte
}

type Response struct {
	Msg []byte
	Err error
}
```

There are generic versions of the server/client handlers that allow the use of type
safe implementations for data types that support msgpack marshal/unmarshal.
2023-11-20 17:09:35 -08:00

84 lines
2.5 KiB
Go

// Copyright (c) 2015-2023 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package cmd
import (
"context"
"crypto/tls"
"sync/atomic"
"github.com/minio/minio-go/v7/pkg/set"
"github.com/minio/minio/internal/fips"
"github.com/minio/minio/internal/grid"
xhttp "github.com/minio/minio/internal/http"
"github.com/minio/minio/internal/rest"
)
// globalGrid is the global grid manager.
var globalGrid atomic.Pointer[grid.Manager]
// globalGridStart is a channel that will block startup of grid connections until closed.
var globalGridStart = make(chan struct{})
func initGlobalGrid(ctx context.Context, eps EndpointServerPools) error {
seenHosts := set.NewStringSet()
var hosts []string
var local string
for _, ep := range eps {
for _, endpoint := range ep.Endpoints {
u := endpoint.GridHost()
if seenHosts.Contains(u) {
continue
}
seenHosts.Add(u)
// Set local endpoint
if endpoint.IsLocal {
local = u
}
hosts = append(hosts, u)
}
}
lookupHost := globalDNSCache.LookupHost
if IsKubernetes() || IsDocker() {
lookupHost = nil
}
g, err := grid.NewManager(ctx, grid.ManagerOptions{
Dialer: grid.ContextDialer(xhttp.DialContextWithLookupHost(lookupHost, xhttp.NewInternodeDialContext(rest.DefaultTimeout, globalTCPOptions))),
Local: local,
Hosts: hosts,
AddAuth: newCachedAuthToken(),
AuthRequest: storageServerRequestValidate,
BlockConnect: globalGridStart,
TLSConfig: &tls.Config{
RootCAs: globalRootCAs,
CipherSuites: fips.TLSCiphers(),
CurvePreferences: fips.TLSCurveIDs(),
},
// Record incoming and outgoing bytes.
Incoming: globalConnStats.incInternodeInputBytes,
Outgoing: globalConnStats.incInternodeOutputBytes,
TraceTo: globalTrace,
})
if err != nil {
return err
}
globalGrid.Store(g)
return nil
}