Files
play-with-docker/router/l2/l2.go
2017-08-03 11:55:53 -03:00

135 lines
2.7 KiB
Go

package main
import (
"context"
"encoding/json"
"fmt"
"log"
"net"
"os"
"github.com/docker/docker/api/types"
"github.com/docker/docker/api/types/filters"
"github.com/docker/docker/api/types/network"
"github.com/docker/docker/client"
"github.com/play-with-docker/play-with-docker/config"
"github.com/play-with-docker/play-with-docker/router"
)
func director(protocol router.Protocol, host string) (*net.TCPAddr, error) {
info, err := router.DecodeHost(host)
if err != nil {
return nil, err
}
port := info.Port
if info.EncodedPort > 0 {
port = info.EncodedPort
}
if port == 0 {
if protocol == router.ProtocolHTTP {
port = 80
} else if protocol == router.ProtocolHTTPS {
port = 443
} else if protocol == router.ProtocolSSH {
port = 22
} else if protocol == router.ProtocolDNS {
port = 53
}
}
t, err := net.ResolveTCPAddr("tcp4", fmt.Sprintf("%s:%d", info.InstanceIP, port))
if err != nil {
return nil, err
}
return t, nil
}
func connectNetworks() error {
ctx := context.Background()
c, err := client.NewEnvClient()
if err != nil {
log.Fatal(err)
}
defer c.Close()
f, err := os.Open(config.SessionsFile)
if err != nil {
return err
}
defer f.Close()
networks := map[string]*network.EndpointSettings{}
err = json.NewDecoder(f).Decode(&networks)
if err != nil {
return err
}
for netId, opts := range networks {
settings := &network.EndpointSettings{}
settings.IPAddress = opts.IPAddress
log.Printf("Connected to network [%s] with ip [%s]\n", netId, opts.IPAddress)
c.NetworkConnect(ctx, netId, config.PWDContainerName, settings)
}
return nil
}
func monitorNetworks() {
c, err := client.NewEnvClient()
if err != nil {
log.Fatal(err)
}
defer c.Close()
ctx := context.Background()
args := filters.NewArgs()
cmsg, _ := c.Events(ctx, types.EventsOptions{Filters: args})
for {
select {
case m := <-cmsg:
if m.Type == "network" {
// Router has been connected to a new network. Let's get all connections and store them in case of restart.
container, err := c.ContainerInspect(ctx, config.PWDContainerName)
if err != nil {
log.Println(err)
return
}
f, err := os.Create(config.SessionsFile)
if err != nil {
log.Println(err)
return
}
err = json.NewEncoder(f).Encode(container.NetworkSettings.Networks)
if err != nil {
log.Println(err)
return
}
log.Println("Saved networks")
}
}
}
}
func main() {
config.ParseFlags()
err := connectNetworks()
if err != nil && !os.IsNotExist(err) {
log.Fatal("connect networks:", err)
}
go monitorNetworks()
r := router.NewRouter(director, config.SSHKeyPath)
r.ListenAndWait(":443", ":53", ":22")
defer r.Close()
}