lnd/channeldb/kvdb/etcd/embed.go
Andras Banki-Horvath 137dee04e8 channeldb+kvdb: an extended STM on top of etcd clientv3
This commit adds an extended STM, similar to what available in etcd's
clientv3 module. This incarnation of said STM supports additional
features, like positioning in key intervals while taking into account
deletes and writes as well. This is a preliminary work to support all
features of the kvdb interface.
2020-05-22 11:26:24 +02:00

73 lines
1.5 KiB
Go

package etcd
import (
"fmt"
"net"
"net/url"
"time"
"github.com/coreos/etcd/embed"
)
const (
// readyTimeout is the time until the embedded etcd instance should start.
readyTimeout = 10 * time.Second
)
// getFreePort returns a random open TCP port.
func getFreePort() int {
ln, err := net.Listen("tcp", "[::]:0")
if err != nil {
panic(err)
}
port := ln.Addr().(*net.TCPAddr).Port
err = ln.Close()
if err != nil {
panic(err)
}
return port
}
// NewEmbeddedEtcdInstance creates an embedded etcd instance for testing,
// listening on random open ports. Returns the backend config and a cleanup
// func that will stop the etcd instance.
func NewEmbeddedEtcdInstance(path string) (*BackendConfig, func(), error) {
cfg := embed.NewConfig()
cfg.Dir = path
// To ensure that we can submit large transactions.
cfg.MaxTxnOps = 1000
// Listen on random free ports.
clientURL := fmt.Sprintf("127.0.0.1:%d", getFreePort())
peerURL := fmt.Sprintf("127.0.0.1:%d", getFreePort())
cfg.LCUrls = []url.URL{{Host: clientURL}}
cfg.LPUrls = []url.URL{{Host: peerURL}}
etcd, err := embed.StartEtcd(cfg)
if err != nil {
return nil, nil, err
}
select {
case <-etcd.Server.ReadyNotify():
case <-time.After(readyTimeout):
etcd.Close()
return nil, nil,
fmt.Errorf("etcd failed to start after: %v", readyTimeout)
}
connConfig := &BackendConfig{
Host: "http://" + peerURL,
User: "user",
Pass: "pass",
}
return connConfig, func() {
etcd.Close()
}, nil
}