podman network label support

Add label support for podman network create. Use the `args`
field in the cni config file to store the podman labels.
Use `podman_labels` as key name and store the labels as
map[string]string.

For reference: https://github.com/containernetworking/cni/blob/master/CONVENTIONS.md#args-in-network-config
https://github.com/containernetworking/cni/blob/spec-v0.4.0/SPEC.md#network-configuration

Example snippet:

```
...
"args": {
	"podman_labels": {
		"key1":"value1",
		"key2":"value2"
	}
}
...
```

Make podman network list support several filters. Supported filters are name,
plugin, driver and label. Filters with different keys work exclusive. Several label
filters work exclusive and the other filter keys are working inclusive.

Also adjust the compat api to support labels in network create and list.

Breaking changes:

- podman network ls -f shortform is used for --filter instead --format
This matches docker and other podman commands (container ps, volume ps)

- libpod network list endpoint filter parameter is removed. Instead the
filters paramter should be used as json encoded map[string][]string.

Signed-off-by: Paul Holzinger <paul.holzinger@web.de>

2 files changed, 31 insertions, 8 deletions

diff --git a/cmd/podman/networks/create.go b/cmd/podman/networks/create.go
index 17de2c95d..938b8da77 100644
--- a/cmd/podman/networks/create.go
+++ b/cmd/podman/networks/create.go
@@ -6,9 +6,11 @@ import (
 
 	"github.com/containers/common/pkg/completion"
 	"github.com/containers/podman/v2/cmd/podman/common"
+	"github.com/containers/podman/v2/cmd/podman/parse"
 	"github.com/containers/podman/v2/cmd/podman/registry"
 	"github.com/containers/podman/v2/libpod/define"
 	"github.com/containers/podman/v2/pkg/domain/entities"
+	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 )
 
@@ -27,6 +29,7 @@ var (
 
 var (
 	networkCreateOptions entities.NetworkCreateOptions
+	labels               []string
 )
 
 func networkCreateFlags(cmd *cobra.Command) {
@@ -50,6 +53,10 @@ func networkCreateFlags(cmd *cobra.Command) {
 	flags.StringVar(&networkCreateOptions.MacVLAN, macvlanFlagName, "", "create a Macvlan connection based on this device")
 	_ = cmd.RegisterFlagCompletionFunc(macvlanFlagName, completion.AutocompleteNone)
 
+	labelFlagName := "label"
+	flags.StringArrayVar(&labels, labelFlagName, nil, "set metadata on a network")
+	_ = cmd.RegisterFlagCompletionFunc(labelFlagName, completion.AutocompleteNone)
+
 	// TODO not supported yet
 	// flags.StringVar(&networkCreateOptions.IPamDriver, "ipam-driver", "",  "IP Address Management Driver")
 
@@ -81,6 +88,11 @@ func networkCreate(cmd *cobra.Command, args []string) error {
 		}
 		name = args[0]
 	}
+	var err error
+	networkCreateOptions.Labels, err = parse.GetAllLabels([]string{}, labels)
+	if err != nil {
+		return errors.Wrap(err, "failed to parse labels")
+	}
 	response, err := registry.ContainerEngine().NetworkCreate(registry.Context(), name, networkCreateOptions)
 	if err != nil {
 		return err
diff --git a/cmd/podman/networks/list.go b/cmd/podman/networks/list.go
index dcba3f186..6e6bbb07d 100644
--- a/cmd/podman/networks/list.go
+++ b/cmd/podman/networks/list.go
@@ -16,6 +16,7 @@ import (
 	"github.com/containers/podman/v2/cmd/podman/validate"
 	"github.com/containers/podman/v2/libpod/network"
 	"github.com/containers/podman/v2/pkg/domain/entities"
+	"github.com/pkg/errors"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 )
@@ -35,17 +36,18 @@ var (
 
 var (
 	networkListOptions entities.NetworkListOptions
+	filters            []string
 )
 
 func networkListFlags(flags *pflag.FlagSet) {
 	formatFlagName := "format"
-	flags.StringVarP(&networkListOptions.Format, formatFlagName, "f", "", "Pretty-print networks to JSON or using a Go template")
+	flags.StringVar(&networkListOptions.Format, formatFlagName, "", "Pretty-print networks to JSON or using a Go template")
 	_ = networklistCommand.RegisterFlagCompletionFunc(formatFlagName, common.AutocompleteJSONFormat)
 
 	flags.BoolVarP(&networkListOptions.Quiet, "quiet", "q", false, "display only names")
 
 	filterFlagName := "filter"
-	flags.StringVarP(&networkListOptions.Filter, filterFlagName, "", "", "Provide filter values (e.g. 'name=podman')")
+	flags.StringArrayVarP(&filters, filterFlagName, "f", nil, "Provide filter values (e.g. 'name=podman')")
 	_ = networklistCommand.RegisterFlagCompletionFunc(filterFlagName, common.AutocompleteNetworkFilters)
 
 }
@@ -61,14 +63,14 @@ func init() {
 }
 
 func networkList(cmd *cobra.Command, args []string) error {
-	// validate the filter pattern.
-	if len(networkListOptions.Filter) > 0 {
-		tokens := strings.Split(networkListOptions.Filter, "=")
-		if len(tokens) != 2 {
-			return fmt.Errorf("invalid filter syntax : %s", networkListOptions.Filter)
+	networkListOptions.Filters = make(map[string][]string)
+	for _, f := range filters {
+		split := strings.SplitN(f, "=", 2)
+		if len(split) == 1 {
+			return errors.Errorf("invalid filter %q", f)
 		}
+		networkListOptions.Filters[split[0]] = append(networkListOptions.Filters[split[0]], split[1])
 	}
-
 	responses, err := registry.ContainerEngine().NetworkList(registry.Context(), networkListOptions)
 	if err != nil {
 		return err
@@ -93,6 +95,7 @@ func networkList(cmd *cobra.Command, args []string) error {
 		"CNIVersion": "version",
 		"Version":    "version",
 		"Plugins":    "plugins",
+		"Labels":     "labels",
 	})
 	renderHeaders := true
 	row := "{{.Name}}\t{{.Version}}\t{{.Plugins}}\n"
@@ -144,3 +147,11 @@ func (n ListPrintReports) Version() string {
 func (n ListPrintReports) Plugins() string {
 	return network.GetCNIPlugins(n.NetworkConfigList)
 }
+
+func (n ListPrintReports) Labels() string {
+	list := make([]string, 0, len(n.NetworkListReport.Labels))
+	for k, v := range n.NetworkListReport.Labels {
+		list = append(list, k+"="+v)
+	}
+	return strings.Join(list, ",")
+}