Add volume prune --filter support

This change adds support for the `--filter` / `?filters` arguments on
the `podman volume prune` subcommand.

  * Adds ParseFilterArgumentsIntoFilters helper for consistent
    Filter string slice handling
  * Adds `--filter` support to podman volume prune cli
  * Adds `?filters...` support to podman volume prune api
  * Updates apiv2 / e2e tests

Closes #8672

Signed-off-by: Baron Lenardson <lenardson.baron@gmail.com>

11 files changed, 114 insertions, 21 deletions

diff --git a/pkg/api/handlers/compat/volumes.go b/pkg/api/handlers/compat/volumes.go
index 71b848932..f76e18ee3 100644
--- a/pkg/api/handlers/compat/volumes.go
+++ b/pkg/api/handlers/compat/volumes.go
@@ -3,6 +3,7 @@ package compat
 import (
 	"encoding/json"
 	"net/http"
+	"net/url"
 	"time"
 
 	"github.com/containers/podman/v2/libpod"
@@ -254,14 +255,15 @@ func PruneVolumes(w http.ResponseWriter, r *http.Request) {
 		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String()))
 		return
 	}
-	// TODO: We have no ability to pass pruning filters to `PruneVolumes()` so
-	// we'll explicitly reject the request if we see any
-	if len(query.Filters) > 0 {
-		utils.InternalServerError(w, errors.New("filters for pruning volumes is not implemented"))
+
+	f := (url.Values)(query.Filters)
+	filterFuncs, err := filters.GenerateVolumeFilters(f)
+	if err != nil {
+		utils.Error(w, "Something when wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse filters for %s", f.Encode()))
 		return
 	}
 
-	pruned, err := runtime.PruneVolumes(r.Context())
+	pruned, err := runtime.PruneVolumes(r.Context(), filterFuncs)
 	if err != nil {
 		utils.InternalServerError(w, err)
 		return
diff --git a/pkg/api/handlers/libpod/volumes.go b/pkg/api/handlers/libpod/volumes.go
index b0d40fd8b..b02a6a8ce 100644
--- a/pkg/api/handlers/libpod/volumes.go
+++ b/pkg/api/handlers/libpod/volumes.go
@@ -3,6 +3,7 @@ package libpod
 import (
 	"encoding/json"
 	"net/http"
+	"net/url"
 
 	"github.com/containers/podman/v2/libpod"
 	"github.com/containers/podman/v2/libpod/define"
@@ -180,8 +181,25 @@ func PruneVolumes(w http.ResponseWriter, r *http.Request) {
 func pruneVolumesHelper(r *http.Request) ([]*entities.VolumePruneReport, error) {
 	var (
 		runtime = r.Context().Value("runtime").(*libpod.Runtime)
+		decoder = r.Context().Value("decoder").(*schema.Decoder)
 	)
-	pruned, err := runtime.PruneVolumes(r.Context())
+	query := struct {
+		Filters map[string][]string `schema:"filters"`
+	}{
+		// override any golang type defaults
+	}
+
+	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
+		return nil, err
+	}
+
+	f := (url.Values)(query.Filters)
+	filterFuncs, err := filters.GenerateVolumeFilters(f)
+	if err != nil {
+		return nil, err
+	}
+
+	pruned, err := runtime.PruneVolumes(r.Context(), filterFuncs)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/bindings/test/volumes_test.go b/pkg/bindings/test/volumes_test.go
index dc90d4d00..861a02441 100644
--- a/pkg/bindings/test/volumes_test.go
+++ b/pkg/bindings/test/volumes_test.go
@@ -144,16 +144,15 @@ var _ = Describe("Podman volumes", func() {
 		Expect(vols[0].Name).To(Equal("homer"))
 	})
 
-	// TODO we need to add filtering to tests
 	It("prune unused volume", func() {
 		// Pruning when no volumes present should be ok
-		_, err := volumes.Prune(connText)
+		_, err := volumes.Prune(connText, nil)
 		Expect(err).To(BeNil())
 
 		// Removing an unused volume should work
 		_, err = volumes.Create(connText, entities.VolumeCreateOptions{})
 		Expect(err).To(BeNil())
-		vols, err := volumes.Prune(connText)
+		vols, err := volumes.Prune(connText, nil)
 		Expect(err).To(BeNil())
 		Expect(len(vols)).To(BeNumerically("==", 1))
 
@@ -163,11 +162,45 @@ var _ = Describe("Podman volumes", func() {
 		Expect(err).To(BeNil())
 		session := bt.runPodman([]string{"run", "-dt", "-v", fmt.Sprintf("%s:/homer", "homer"), "--name", "vtest", alpine.name, "top"})
 		session.Wait(45)
-		vols, err = volumes.Prune(connText)
+		vols, err = volumes.Prune(connText, nil)
 		Expect(err).To(BeNil())
 		Expect(len(vols)).To(BeNumerically("==", 1))
 		_, err = volumes.Inspect(connText, "homer")
 		Expect(err).To(BeNil())
+
+		// Removing volume with non matching filter shouldn't prune any volumes
+		filters := make(map[string][]string)
+		filters["label"] = []string{"label1=idontmatch"}
+		_, err = volumes.Create(connText, entities.VolumeCreateOptions{Label: map[string]string{
+			"label1": "value1",
+		}})
+		Expect(err).To(BeNil())
+		vols, err = volumes.Prune(connText, filters)
+		Expect(err).To(BeNil())
+		Expect(len(vols)).To(BeNumerically("==", 0))
+		vol2, err := volumes.Create(connText, entities.VolumeCreateOptions{Label: map[string]string{
+			"label1": "value2",
+		}})
+		Expect(err).To(BeNil())
+		_, err = volumes.Create(connText, entities.VolumeCreateOptions{Label: map[string]string{
+			"label1": "value3",
+		}})
+		Expect(err).To(BeNil())
+
+		// Removing volume with matching filter label and value should remove specific entry
+		filters = make(map[string][]string)
+		filters["label"] = []string{"label1=value2"}
+		vols, err = volumes.Prune(connText, filters)
+		Expect(err).To(BeNil())
+		Expect(len(vols)).To(BeNumerically("==", 1))
+		Expect(vols[0].Id).To(Equal(vol2.Name))
+
+		// Removing volumes with matching filter label should remove all matching volumes
+		filters = make(map[string][]string)
+		filters["label"] = []string{"label1"}
+		vols, err = volumes.Prune(connText, filters)
+		Expect(err).To(BeNil())
+		Expect(len(vols)).To(BeNumerically("==", 2))
 	})
 
 })
diff --git a/pkg/bindings/volumes/volumes.go b/pkg/bindings/volumes/volumes.go
index 00f1e5720..b1be257b8 100644
--- a/pkg/bindings/volumes/volumes.go
+++ b/pkg/bindings/volumes/volumes.go
@@ -75,7 +75,7 @@ func List(ctx context.Context, filters map[string][]string) ([]*entities.VolumeL
 }
 
 // Prune removes unused volumes from the local filesystem.
-func Prune(ctx context.Context) ([]*entities.VolumePruneReport, error) {
+func Prune(ctx context.Context, filters map[string][]string) ([]*entities.VolumePruneReport, error) {
 	var (
 		pruned []*entities.VolumePruneReport
 	)
@@ -83,7 +83,15 @@ func Prune(ctx context.Context) ([]*entities.VolumePruneReport, error) {
 	if err != nil {
 		return nil, err
 	}
-	response, err := conn.DoRequest(nil, http.MethodPost, "/volumes/prune", nil, nil)
+	params := url.Values{}
+	if len(filters) > 0 {
+		strFilters, err := bindings.FiltersToString(filters)
+		if err != nil {
+			return nil, err
+		}
+		params.Set("filters", strFilters)
+	}
+	response, err := conn.DoRequest(nil, http.MethodPost, "/volumes/prune", params, nil)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/domain/entities/engine_container.go b/pkg/domain/entities/engine_container.go
index 5ad475133..ac9073402 100644
--- a/pkg/domain/entities/engine_container.go
+++ b/pkg/domain/entities/engine_container.go
@@ -80,6 +80,6 @@ type ContainerEngine interface {
 	VolumeCreate(ctx context.Context, opts VolumeCreateOptions) (*IDOrNameResponse, error)
 	VolumeInspect(ctx context.Context, namesOrIds []string, opts InspectOptions) ([]*VolumeInspectReport, []error, error)
 	VolumeList(ctx context.Context, opts VolumeListOptions) ([]*VolumeListReport, error)
-	VolumePrune(ctx context.Context) ([]*VolumePruneReport, error)
+	VolumePrune(ctx context.Context, options VolumePruneOptions) ([]*VolumePruneReport, error)
 	VolumeRm(ctx context.Context, namesOrIds []string, opts VolumeRmOptions) ([]*VolumeRmReport, error)
 }
diff --git a/pkg/domain/entities/volumes.go b/pkg/domain/entities/volumes.go
index 1bc1e4301..e6b29e374 100644
--- a/pkg/domain/entities/volumes.go
+++ b/pkg/domain/entities/volumes.go
@@ -1,6 +1,7 @@
 package entities
 
 import (
+	"net/url"
 	"time"
 
 	docker_api_types "github.com/docker/docker/api/types"
@@ -109,6 +110,12 @@ type VolumeInspectReport struct {
 	*VolumeConfigResponse
 }
 
+// VolumePruneOptions describes the options needed
+// to prune a volume from the CLI
+type VolumePruneOptions struct {
+	Filters url.Values `json:"filters" schema:"filters"`
+}
+
 type VolumePruneReport struct {
 	Err error
 	Id  string //nolint
diff --git a/pkg/domain/filters/helpers.go b/pkg/domain/filters/helpers.go
new file mode 100644
index 000000000..6a5fb68b1
--- /dev/null
+++ b/pkg/domain/filters/helpers.go
@@ -0,0 +1,20 @@
+package filters
+
+import (
+	"net/url"
+	"strings"
+
+	"github.com/pkg/errors"
+)
+
+func ParseFilterArgumentsIntoFilters(filters []string) (url.Values, error) {
+	parsedFilters := make(url.Values)
+	for _, f := range filters {
+		t := strings.SplitN(f, "=", 2)
+		if len(t) < 2 {
+			return parsedFilters, errors.Errorf("filter input must be in the form of filter=value: %s is invalid", f)
+		}
+		parsedFilters.Add(t[0], t[1])
+	}
+	return parsedFilters, nil
+}
diff --git a/pkg/domain/filters/volumes.go b/pkg/domain/filters/volumes.go
index 7819d3cdf..69bef4961 100644
--- a/pkg/domain/filters/volumes.go
+++ b/pkg/domain/filters/volumes.go
@@ -1,13 +1,14 @@
 package filters
 
 import (
+	"net/url"
 	"strings"
 
 	"github.com/containers/podman/v2/libpod"
 	"github.com/pkg/errors"
 )
 
-func GenerateVolumeFilters(filters map[string][]string) ([]libpod.VolumeFilter, error) {
+func GenerateVolumeFilters(filters url.Values) ([]libpod.VolumeFilter, error) {
 	var vf []libpod.VolumeFilter
 	for filter, v := range filters {
 		for _, val := range v {
diff --git a/pkg/domain/infra/abi/system.go b/pkg/domain/infra/abi/system.go
index 7ed58092b..e4ed0a6be 100644
--- a/pkg/domain/infra/abi/system.go
+++ b/pkg/domain/infra/abi/system.go
@@ -214,7 +214,7 @@ func (ic *ContainerEngine) SystemPrune(ctx context.Context, options entities.Sys
 			systemPruneReport.ImagePruneReport.Report.Id = append(systemPruneReport.ImagePruneReport.Report.Id, results...)
 		}
 		if options.Volume {
-			volumePruneReport, err := ic.pruneVolumesHelper(ctx)
+			volumePruneReport, err := ic.pruneVolumesHelper(ctx, nil)
 			if err != nil {
 				return nil, err
 			}
diff --git a/pkg/domain/infra/abi/volumes.go b/pkg/domain/infra/abi/volumes.go
index a7262f61b..515e52754 100644
--- a/pkg/domain/infra/abi/volumes.go
+++ b/pkg/domain/infra/abi/volumes.go
@@ -127,12 +127,16 @@ func (ic *ContainerEngine) VolumeInspect(ctx context.Context, namesOrIds []strin
 	return reports, errs, nil
 }
 
-func (ic *ContainerEngine) VolumePrune(ctx context.Context) ([]*entities.VolumePruneReport, error) {
-	return ic.pruneVolumesHelper(ctx)
+func (ic *ContainerEngine) VolumePrune(ctx context.Context, options entities.VolumePruneOptions) ([]*entities.VolumePruneReport, error) {
+	filterFuncs, err := filters.GenerateVolumeFilters(options.Filters)
+	if err != nil {
+		return nil, err
+	}
+	return ic.pruneVolumesHelper(ctx, filterFuncs)
 }
 
-func (ic *ContainerEngine) pruneVolumesHelper(ctx context.Context) ([]*entities.VolumePruneReport, error) {
-	pruned, err := ic.Libpod.PruneVolumes(ctx)
+func (ic *ContainerEngine) pruneVolumesHelper(ctx context.Context, filterFuncs []libpod.VolumeFilter) ([]*entities.VolumePruneReport, error) {
+	pruned, err := ic.Libpod.PruneVolumes(ctx, filterFuncs)
 	if err != nil {
 		return nil, err
 	}
diff --git a/pkg/domain/infra/tunnel/volumes.go b/pkg/domain/infra/tunnel/volumes.go
index c0df2bb7b..b431fc8bd 100644
--- a/pkg/domain/infra/tunnel/volumes.go
+++ b/pkg/domain/infra/tunnel/volumes.go
@@ -68,8 +68,8 @@ func (ic *ContainerEngine) VolumeInspect(ctx context.Context, namesOrIds []strin
 	return reports, errs, nil
 }
 
-func (ic *ContainerEngine) VolumePrune(ctx context.Context) ([]*entities.VolumePruneReport, error) {
-	return volumes.Prune(ic.ClientCxt)
+func (ic *ContainerEngine) VolumePrune(ctx context.Context, opts entities.VolumePruneOptions) ([]*entities.VolumePruneReport, error) {
+	return volumes.Prune(ic.ClientCxt, (map[string][]string)(opts.Filters))
 }
 
 func (ic *ContainerEngine) VolumeList(ctx context.Context, opts entities.VolumeListOptions) ([]*entities.VolumeListReport, error) {