add tests and move from label to constraint

Signed-off-by: Victor Vieux <vieux@docker.com>

contrib/demo.sh

@@ -43,7 +43,7 @@ docker run -d -p 80:80 nginx
 # clean up cluster
 docker rm -f `docker ps -aq`
 
-docker run -d -e constraint:operatingsystem=fedora redis
+docker run -d -e "constraint:operatingsystem=fedora*" redis
 docker ps
 
 docker run -d -e constraint:storagedriver=devicemapper redis

flags.go

@@ -57,7 +57,7 @@ var (
 	}
 	flFilter = cli.StringSliceFlag{
 		Name:  "filter, f",
-		Usage: "Filter to use [health, label, port]",
-		Value: &cli.StringSlice{"health", "label", "port"},
+		Usage: "Filter to use [constraint, health, port]",
+		Value: &cli.StringSlice{"constraint", "health", "port"},
 	}
 )

scheduler/filter/constraint.go

@@ -10,11 +10,11 @@ import (
 	"github.com/samalba/dockerclient"
 )
 
-// LabelFilter selects only nodes that match certain labels.
-type LabelFilter struct {
+// ConstraintFilter selects only nodes that match certain labels.
+type ConstraintFilter struct {
 }
 
-func (f *LabelFilter) extractConstraints(env []string) map[string]string {
+func (f *ConstraintFilter) extractConstraints(env []string) map[string]string {
 	constraints := make(map[string]string)
 	for _, e := range env {
 		if strings.HasPrefix(e, "constraint:") {
@@ -26,7 +26,7 @@ func (f *LabelFilter) extractConstraints(env []string) map[string]string {
 	return constraints
 }
 
-func (f *LabelFilter) Filter(config *dockerclient.ContainerConfig, nodes []*cluster.Node) ([]*cluster.Node, error) {
+func (f *ConstraintFilter) 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) + "$"

scheduler/filter/constraint_test.go

@@ -8,9 +8,9 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestLabeleFilter(t *testing.T) {
+func TestConstrainteFilter(t *testing.T) {
 	var (
-		f     = LabelFilter{}
+		f     = ConstraintFilter{}
 		nodes = []*cluster.Node{
 			cluster.NewNode("node-0"),
 			cluster.NewNode("node-1"),
@@ -23,22 +23,25 @@ func TestLabeleFilter(t *testing.T) {
 	nodes[0].ID = "node-0-id"
 	nodes[0].Name = "node-0-name"
 	nodes[0].Labels = map[string]string{
-		"name":  "node0",
-		"group": "1",
+		"name":   "node0",
+		"group":  "1",
+		"region": "us-west",
 	}
 
 	nodes[1].ID = "node-1-id"
 	nodes[1].Name = "node-1-name"
 	nodes[1].Labels = map[string]string{
-		"name":  "node1",
-		"group": "1",
+		"name":   "node1",
+		"group":  "1",
+		"region": "us-east",
 	}
 
 	nodes[2].ID = "node-2-id"
 	nodes[2].Name = "node-2-name"
 	nodes[2].Labels = map[string]string{
-		"name":  "node2",
-		"group": "2",
+		"name":   "node2",
+		"group":  "2",
+		"region": "eu",
 	}
 
 	// Without constraints we should get the unfiltered list of nodes back.
@@ -91,4 +94,17 @@ func TestLabeleFilter(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Len(t, result, 1)
 	assert.Equal(t, result[0], nodes[0])
+
+	// Check matching
+	result, err = f.Filter(&dockerclient.ContainerConfig{
+		Env: []string{"constraint:region=us"},
+	}, nodes)
+	assert.Error(t, err)
+	assert.Len(t, result, 0)
+
+	result, err = f.Filter(&dockerclient.ContainerConfig{
+		Env: []string{"constraint:region=us*"},
+	}, nodes)
+	assert.NoError(t, err)
+	assert.Len(t, result, 2)
 }

scheduler/filter/filter.go

@@ -20,9 +20,9 @@ var (
 
 func init() {
 	filters = map[string]Filter{
-		"health": &HealthFilter{},
-		"label":  &LabelFilter{},
-		"port":   &PortFilter{},
+		"health":     &HealthFilter{},
+		"constraint": &ConstraintFilter{},
+		"port":       &PortFilter{},
 	}
 }