Review corrections pass #2

Add API review comments to correct documentation and endpoints.  Also, add a libpode prune method to reduce code duplication.  Only used right now for the API but when the remote client is wired, we will switch over there too.

Signed-off-by: Brent Baude <bbaude@redhat.com>

pkg/api/handlers/containers.go

@@ -2,6 +2,7 @@ package handlers
 
 import (
 	"fmt"
+	"github.com/docker/docker/api/types"
 	"net/http"
 
 	"github.com/containers/libpod/libpod"
@@ -192,3 +193,55 @@ func RestartContainer(w http.ResponseWriter, r *http.Request) {
 	// Success
 	utils.WriteResponse(w, http.StatusNoContent, "")
 }
+
+func PruneContainers(w http.ResponseWriter, r *http.Request) {
+	var (
+		delContainers []string
+		space         int64
+	)
+	runtime := r.Context().Value("runtime").(*libpod.Runtime)
+	decoder := r.Context().Value("decoder").(*schema.Decoder)
+
+	query := struct {
+		Filters map[string][]string `schema:"filter"`
+	}{}
+	if err := decoder.Decode(&query, r.URL.Query()); err != nil {
+		utils.Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "Failed to parse parameters for %s", r.URL.String()))
+		return
+	}
+
+	filterFuncs, err := utils.GenerateFilterFuncsFromMap(runtime, query.Filters)
+	if err != nil {
+		utils.InternalServerError(w, err)
+		return
+	}
+	prunedContainers, pruneErrors, err := runtime.PruneContainers(filterFuncs)
+	if err != nil {
+		utils.InternalServerError(w, err)
+		return
+	}
+
+	// Libpod response differs
+	if utils.IsLibpodRequest(r) {
+		var response []LibpodContainersPruneReport
+		for ctrID, size := range prunedContainers {
+			response = append(response, LibpodContainersPruneReport{ID: ctrID, SpaceReclaimed: size})
+		}
+		for ctrID, err := range pruneErrors {
+			response = append(response, LibpodContainersPruneReport{ID: ctrID, PruneError: err.Error()})
+		}
+		utils.WriteResponse(w, http.StatusOK, response)
+		return
+	}
+	for ctrID, size := range prunedContainers {
+		if pruneErrors[ctrID] == nil {
+			space += size
+			delContainers = append(delContainers, ctrID)
+		}
+	}
+	report := types.ContainersPruneReport{
+		ContainersDeleted: delContainers,
+		SpaceReclaimed:    uint64(space),
+	}
+	utils.WriteResponse(w, http.StatusOK, report)
+}