docker/links/links.go

138 строки
3.3 KiB
Go

package links
import (
"fmt"
"github.com/dotcloud/docker/engine"
"github.com/dotcloud/docker/nat"
"path"
"strings"
)
type Link struct {
ParentIP string
ChildIP string
Name string
ChildEnvironment []string
Ports []nat.Port
IsEnabled bool
eng *engine.Engine
}
func NewLink(parentIP, childIP, name string, env []string, exposedPorts map[nat.Port]struct{}, eng *engine.Engine) (*Link, error) {
var (
i int
ports = make([]nat.Port, len(exposedPorts))
)
for p := range exposedPorts {
ports[i] = p
i++
}
l := &Link{
Name: name,
ChildIP: childIP,
ParentIP: parentIP,
ChildEnvironment: env,
Ports: ports,
eng: eng,
}
return l, nil
}
func (l *Link) Alias() string {
_, alias := path.Split(l.Name)
return alias
}
func (l *Link) ToEnv() []string {
env := []string{}
alias := strings.Replace(strings.ToUpper(l.Alias()), "-", "_", -1)
if p := l.getDefaultPort(); p != nil {
env = append(env, fmt.Sprintf("%s_PORT=%s://%s:%s", alias, p.Proto(), l.ChildIP, p.Port()))
}
// Load exposed ports into the environment
for _, p := range l.Ports {
env = append(env, fmt.Sprintf("%s_PORT_%s_%s=%s://%s:%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Proto(), l.ChildIP, p.Port()))
env = append(env, fmt.Sprintf("%s_PORT_%s_%s_ADDR=%s", alias, p.Port(), strings.ToUpper(p.Proto()), l.ChildIP))
env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PORT=%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Port()))
env = append(env, fmt.Sprintf("%s_PORT_%s_%s_PROTO=%s", alias, p.Port(), strings.ToUpper(p.Proto()), p.Proto()))
}
// Load the linked container's name into the environment
env = append(env, fmt.Sprintf("%s_NAME=%s", alias, l.Name))
if l.ChildEnvironment != nil {
for _, v := range l.ChildEnvironment {
parts := strings.Split(v, "=")
if len(parts) != 2 {
continue
}
// Ignore a few variables that are added during docker build (and not really relevant to linked containers)
if parts[0] == "HOME" || parts[0] == "PATH" {
continue
}
env = append(env, fmt.Sprintf("%s_ENV_%s=%s", alias, parts[0], parts[1]))
}
}
return env
}
// Default port rules
func (l *Link) getDefaultPort() *nat.Port {
var p nat.Port
i := len(l.Ports)
if i == 0 {
return nil
} else if i > 1 {
nat.Sort(l.Ports, func(ip, jp nat.Port) bool {
// If the two ports have the same number, tcp takes priority
// Sort in desc order
return ip.Int() < jp.Int() || (ip.Int() == jp.Int() && strings.ToLower(ip.Proto()) == "tcp")
})
}
p = l.Ports[0]
return &p
}
func (l *Link) Enable() error {
if err := l.toggle("-I", false); err != nil {
return err
}
l.IsEnabled = true
return nil
}
func (l *Link) Disable() {
// We do not care about errors here because the link may not
// exist in iptables
l.toggle("-D", true)
l.IsEnabled = false
}
func (l *Link) toggle(action string, ignoreErrors bool) error {
job := l.eng.Job("link", action)
job.Setenv("ParentIP", l.ParentIP)
job.Setenv("ChildIP", l.ChildIP)
job.SetenvBool("IgnoreErrors", ignoreErrors)
out := make([]string, len(l.Ports))
for i, p := range l.Ports {
out[i] = fmt.Sprintf("%s/%s", p.Port(), p.Proto())
}
job.SetenvList("Ports", out)
if err := job.Run(); err != nil {
// TODO: get ouput from job
return err
}
return nil
}