moby/daemon/links.go
Yuanhong Peng 600ad5c1b7 Remove links when remove container
Steps to reproduce:
```
    # docker run -tid --name aaa ubuntu
    57bfd00ac5559f72eec8c1b32a01fe38427d66687940f74611e65137414f0ada
    # docker run -tid --name bbb --link aaa ubuntu
    23ad18362950f39b638206ab4d1885fd4f50cbd1d16aac9cab8e97e0c8363471
    # docker ps --no-trunc
    CONTAINER ID                                                       IMAGE
    COMMAND             CREATED             STATUS              PORTS
    NAMES
    23ad18362950f39b638206ab4d1885fd4f50cbd1d16aac9cab8e97e0c8363471
    ubuntu              "/bin/bash"         4 seconds ago       Up 3 seconds
    bbb
    57bfd00ac5559f72eec8c1b32a01fe38427d66687940f74611e65137414f0ada
    ubuntu              "/bin/bash"         14 seconds ago      Up 14
    seconds                           aaa,bbb/aaa
    # docker rm -f bbb
    bbb
    # docker ps --no-trunc
    CONTAINER ID                                                       IMAGE
    COMMAND             CREATED             STATUS              PORTS
    NAMES
    57bfd00ac5559f72eec8c1b32a01fe38427d66687940f74611e65137414f0ada
    ubuntu              "/bin/bash"         29 seconds ago      Up 28
    seconds                           aaa,bbb/aaa
    # docker rm --link bbb/aaa
    Error response from daemon: Cannot get parent /bbb for name /bbb/aaa
```

When we rm container `bbb`, we can still see `bbb/aaa` in `docker ps
--no-trunc`. And this link cannot be deleted since container `bbb` has
already been removed.

We should remove links of a container when it is deleted.

Signed-off-by: Yuanhong Peng <pengyuanhong@huawei.com>
2017-07-18 12:09:26 +08:00

91 lines
2.6 KiB
Go

package daemon
import (
"sync"
"github.com/docker/docker/container"
)
// linkIndex stores link relationships between containers, including their specified alias
// The alias is the name the parent uses to reference the child
type linkIndex struct {
// idx maps a parent->alias->child relationship
idx map[*container.Container]map[string]*container.Container
// childIdx maps child->parent->aliases
childIdx map[*container.Container]map[*container.Container]map[string]struct{}
mu sync.Mutex
}
func newLinkIndex() *linkIndex {
return &linkIndex{
idx: make(map[*container.Container]map[string]*container.Container),
childIdx: make(map[*container.Container]map[*container.Container]map[string]struct{}),
}
}
// link adds indexes for the passed in parent/child/alias relationships
func (l *linkIndex) link(parent, child *container.Container, alias string) {
l.mu.Lock()
if l.idx[parent] == nil {
l.idx[parent] = make(map[string]*container.Container)
}
l.idx[parent][alias] = child
if l.childIdx[child] == nil {
l.childIdx[child] = make(map[*container.Container]map[string]struct{})
}
if l.childIdx[child][parent] == nil {
l.childIdx[child][parent] = make(map[string]struct{})
}
l.childIdx[child][parent][alias] = struct{}{}
l.mu.Unlock()
}
// unlink removes the requested alias for the given parent/child
func (l *linkIndex) unlink(alias string, child, parent *container.Container) {
l.mu.Lock()
delete(l.idx[parent], alias)
delete(l.childIdx[child], parent)
l.mu.Unlock()
}
// children maps all the aliases-> children for the passed in parent
// aliases here are the aliases the parent uses to refer to the child
func (l *linkIndex) children(parent *container.Container) map[string]*container.Container {
l.mu.Lock()
children := l.idx[parent]
l.mu.Unlock()
return children
}
// parents maps all the aliases->parent for the passed in child
// aliases here are the aliases the parents use to refer to the child
func (l *linkIndex) parents(child *container.Container) map[string]*container.Container {
l.mu.Lock()
parents := make(map[string]*container.Container)
for parent, aliases := range l.childIdx[child] {
for alias := range aliases {
parents[alias] = parent
}
}
l.mu.Unlock()
return parents
}
// delete deletes all link relationships referencing this container
func (l *linkIndex) delete(container *container.Container) []string {
l.mu.Lock()
var aliases []string
for alias, child := range l.idx[container] {
aliases = append(aliases, alias)
delete(l.childIdx[child], container)
}
delete(l.idx, container)
delete(l.childIdx, container)
l.mu.Unlock()
return aliases
}