add ps style filtering of containers

container/client.go

@@ -3,10 +3,12 @@ package container
 import (
 	"fmt"
 	"io/ioutil"
+	"strings"
 	"time"
 
 	log "github.com/Sirupsen/logrus"
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/api/types/network"
 	dockerclient "github.com/docker/docker/client"
 	"golang.org/x/net/context"
@@ -37,19 +39,20 @@ type Client interface {
 //  * DOCKER_HOST			the docker-engine host to send api requests to
 //  * DOCKER_TLS_VERIFY		whether to verify tls certificates
 //  * DOCKER_API_VERSION	the minimum docker api version to work with
-func NewClient(pullImages bool) Client {
+func NewClient(pullImages bool, filtersSlice []string) Client {
 	cli, err := dockerclient.NewEnvClient()
 
 	if err != nil {
 		log.Fatalf("Error instantiating Docker client: %s", err)
 	}
 
-	return dockerClient{api: cli, pullImages: pullImages}
+	return dockerClient{api: cli, pullImages: pullImages, rawFilters: filtersSlice}
 }
 
 type dockerClient struct {
 	api        *dockerclient.Client
 	pullImages bool
+	rawFilters []string
 }
 
 func (client dockerClient) ListContainers(fn Filter) ([]Container, error) {
@@ -58,9 +61,25 @@ func (client dockerClient) ListContainers(fn Filter) ([]Container, error) {
 
 	log.Debug("Retrieving running containers")
 
+	listOptions := types.ContainerListOptions{}
+
+	if len(client.rawFilters) != 0 {
+		// try to construct filters from the string slice
+		filters := filters.NewArgs()
+		for _, filter := range client.rawFilters {
+			// split by first equals sign
+			filterParts := strings.SplitN(filter, "=", 2)
+			// now add the filter
+			filters.Add(filterParts[0], filterParts[1])
+		}
+		listOptions.All = true
+		listOptions.Filters = filters
+	}
+
 	runningContainers, err := client.api.ContainerList(
 		bg,
-		types.ContainerListOptions{})
+		listOptions,
+	)
 	if err != nil {
 		return nil, err
 	}

main.go

@@ -27,6 +27,7 @@ var (
 	scheduleSpec string
 	cleanup      bool
 	noRestart    bool
+	filters      []string
 )
 
 func init() {
@@ -82,6 +83,10 @@ func main() {
 			Name:  "debug",
 			Usage: "enable debug mode with verbose logging",
 		},
+		cli.StringSliceFlag{
+			Name:  "ps-filter",
+			Usage: "docker ps filters",
+		},
 	}
 
 	if err := app.Run(os.Args); err != nil {
@@ -96,6 +101,7 @@ func before(c *cli.Context) error {
 
 	pollingSet := c.IsSet("interval")
 	cronSet := c.IsSet("schedule")
+	filters = c.GlobalStringSlice("ps-filter")
 
 	if pollingSet && cronSet {
 		log.Fatal("Only schedule or interval can be defined, not both.")
@@ -114,7 +120,7 @@ func before(c *cli.Context) error {
 		return err
 	}
 
-	client = container.NewClient(!c.GlobalBool("no-pull"))
+	client = container.NewClient(!c.GlobalBool("no-pull"), filters)
 	return nil
 }