Add support for negated placement constraint (#1419)

pkg/loader/compose/compose_test.go

@@ -500,11 +500,29 @@ func TestCheckPlacementCustomLabels(t *testing.T) {
 			"node.labels.monitor != xxx",
 		},
 	}
-	output := loadV3Placement(placement.Constraints)
+	output := loadV3Placement(placement)
 
-	expected := map[string]string{"something": "anything"}
+	expected := kobject.Placement{
+		PositiveConstraints: map[string]string{
+			"something": "anything",
+		},
+		NegativeConstraints: map[string]string{
+			"monitor": "xxx",
+		},
+	}
 
-	if output["something"] != expected["something"] {
-		t.Errorf("Expected %s, got %s", expected, output)
+	checkConstraints(t, "positive", output.PositiveConstraints, expected.PositiveConstraints)
+	checkConstraints(t, "negative", output.NegativeConstraints, expected.NegativeConstraints)
+}
+
+func checkConstraints(t *testing.T, caseName string, output, expected map[string]string) {
+	t.Log("Test case:", caseName)
+	if len(output) != len(expected) {
+		t.Errorf("constraints len is not equal, expected %d, got %d", len(expected), len(output))
+	}
+	for key := range output {
+		if output[key] != expected[key] {
+			t.Errorf("%s constraint is not equal, expected %s, got %s", key, expected[key], output[key])
+		}
 	}
 }

pkg/loader/compose/v3.go

@@ -33,7 +33,7 @@ import (
 	"github.com/docker/cli/cli/compose/loader"
 	"github.com/docker/cli/cli/compose/types"
 
-	shlex "github.com/google/shlex"
+	"github.com/google/shlex"
 	"github.com/kubernetes/kompose/pkg/kobject"
 	"github.com/pkg/errors"
 	log "github.com/sirupsen/logrus"
@@ -133,27 +133,43 @@ func parseV3(files []string) (kobject.KomposeObject, error) {
 	return komposeObject, nil
 }
 
-func loadV3Placement(constraints []string) map[string]string {
-	placement := make(map[string]string)
+func loadV3Placement(placement types.Placement) kobject.Placement {
+	komposePlacement := kobject.Placement{
+		PositiveConstraints: make(map[string]string),
+		NegativeConstraints: make(map[string]string),
+	}
+	equal, notEqual := " == ", " != "
 	errMsg := " constraints in placement is not supported, only 'node.hostname', 'engine.labels.operatingsystem' and 'node.labels.xxx' (ex: node.labels.something == anything) is supported as a constraint "
-	for _, j := range constraints {
-		p := strings.Split(j, " == ")
+	for _, j := range placement.Constraints {
+		operator := equal
+		if strings.Contains(j, notEqual) {
+			operator = notEqual
+		}
+		p := strings.Split(j, operator)
 		if len(p) < 2 {
 			log.Warn(p[0], errMsg)
 			continue
 		}
+
+		var key string
 		if p[0] == "node.hostname" {
-			placement["kubernetes.io/hostname"] = p[1]
+			key = "kubernetes.io/hostname"
 		} else if p[0] == "engine.labels.operatingsystem" {
-			placement["beta.kubernetes.io/os"] = p[1]
+			key = "beta.kubernetes.io/os"
 		} else if strings.HasPrefix(p[0], "node.labels.") {
-			label := strings.TrimPrefix(p[0], "node.labels.")
-			placement[label] = p[1]
+			key = strings.TrimPrefix(p[0], "node.labels.")
 		} else {
 			log.Warn(p[0], errMsg)
+			continue
+		}
+
+		if operator == equal {
+			komposePlacement.PositiveConstraints[key] = p[1]
+		} else if operator == notEqual {
+			komposePlacement.NegativeConstraints[key] = p[1]
 		}
 	}
-	return placement
+	return komposePlacement
 }
 
 // Convert the Docker Compose v3 volumes to []string (the old way)
@@ -434,7 +450,7 @@ func dockerComposeToKomposeMapping(composeObject *types.Config) (kobject.Kompose
 		}
 
 		// placement:
-		serviceConfig.Placement = loadV3Placement(composeServiceConfig.Deploy.Placement.Constraints)
+		serviceConfig.Placement = loadV3Placement(composeServiceConfig.Deploy.Placement)
 
 		if composeServiceConfig.Deploy.UpdateConfig != nil {
 			serviceConfig.DeployUpdateConfig = *composeServiceConfig.Deploy.UpdateConfig