mirror of https://github.com/docker/docs.git
70 lines
1.9 KiB
Go
70 lines
1.9 KiB
Go
package filter
|
|
|
|
import (
|
|
"fmt"
|
|
"regexp"
|
|
"strings"
|
|
|
|
log "github.com/Sirupsen/logrus"
|
|
"github.com/docker/swarm/cluster"
|
|
"github.com/samalba/dockerclient"
|
|
)
|
|
|
|
// LabelFilter selects only nodes that match certain labels.
|
|
type LabelFilter struct {
|
|
}
|
|
|
|
func (f *LabelFilter) extractConstraints(env []string) map[string]string {
|
|
constraints := make(map[string]string)
|
|
for _, e := range env {
|
|
if strings.HasPrefix(e, "constraint:") {
|
|
constraint := strings.TrimPrefix(e, "constraint:")
|
|
parts := strings.SplitN(constraint, "=", 2)
|
|
constraints[strings.ToLower(parts[0])] = strings.ToLower(parts[1])
|
|
}
|
|
}
|
|
return constraints
|
|
}
|
|
|
|
func (f *LabelFilter) Filter(config *dockerclient.ContainerConfig, nodes []*cluster.Node) ([]*cluster.Node, error) {
|
|
constraints := f.extractConstraints(config.Env)
|
|
for k, v := range constraints {
|
|
regex := "^" + strings.Replace(v, "*", ".*", -1) + "$"
|
|
log.Debugf("matching constraint: %s=%s", k, regex)
|
|
candidates := []*cluster.Node{}
|
|
for _, node := range nodes {
|
|
switch k {
|
|
case "node":
|
|
// "node" label is a special case pinning a container to a specific node.
|
|
matchedID, err := regexp.MatchString(regex, strings.ToLower(node.ID))
|
|
if err != nil {
|
|
log.Error(err)
|
|
}
|
|
matchedName, err := regexp.MatchString(regex, strings.ToLower(node.Name))
|
|
if err != nil {
|
|
log.Error(err)
|
|
}
|
|
if matchedID || matchedName {
|
|
candidates = append(candidates, node)
|
|
}
|
|
default:
|
|
// By default match the node labels.
|
|
if label, ok := node.Labels[k]; ok {
|
|
matched, err := regexp.MatchString(regex, strings.ToLower(label))
|
|
if err != nil {
|
|
log.Error(err)
|
|
}
|
|
if matched {
|
|
candidates = append(candidates, node)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if len(candidates) == 0 {
|
|
return nil, fmt.Errorf("unable to find a node that satisfies %s == %s", k, v)
|
|
}
|
|
nodes = candidates
|
|
}
|
|
return nodes, nil
|
|
}
|