implement podman update

podman update allows users to change the cgroup configuration of an existing container using the already defined resource limits flags
from podman create/run. The supported flags in crun are:

this command is also now supported in the libpod api via the /libpod/containers/<CID>/update endpoint where
the resource limits are passed inthe request body and follow the OCI resource spec format

–memory
–cpus
–cpuset-cpus
–cpuset-mems
–memory-swap
–memory-reservation
–cpu-shares
–cpu-quota
–cpu-period
–blkio-weight
–cpu-rt-period
–cpu-rt-runtime
-device-read-bps
-device-write-bps
-device-read-iops
-device-write-iops
-memory-swappiness
-blkio-weight-device

resolves #15067

Signed-off-by: Charlie Doern <cdoern@redhat.com>

4 files changed, 65 insertions, 0 deletions

diff --git a/pkg/api/handlers/libpod/containers.go b/pkg/api/handlers/libpod/containers.go
index 5d85d4009..d1460569f 100644
--- a/pkg/api/handlers/libpod/containers.go
+++ b/pkg/api/handlers/libpod/containers.go
@@ -1,6 +1,7 @@
 package libpod
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"io/ioutil"
@@ -10,6 +11,7 @@ import (
 
 	"github.com/containers/podman/v4/libpod"
 	"github.com/containers/podman/v4/libpod/define"
+	"github.com/containers/podman/v4/pkg/api/handlers"
 	"github.com/containers/podman/v4/pkg/api/handlers/compat"
 	"github.com/containers/podman/v4/pkg/api/handlers/utils"
 	api "github.com/containers/podman/v4/pkg/api/types"
@@ -17,6 +19,7 @@ import (
 	"github.com/containers/podman/v4/pkg/domain/infra/abi"
 	"github.com/containers/podman/v4/pkg/util"
 	"github.com/gorilla/schema"
+	"github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/sirupsen/logrus"
 )
 
@@ -391,6 +394,28 @@ func InitContainer(w http.ResponseWriter, r *http.Request) {
 	utils.WriteResponse(w, http.StatusNoContent, "")
 }
 
+func UpdateContainer(w http.ResponseWriter, r *http.Request) {
+	name := utils.GetName(r)
+	runtime := r.Context().Value(api.RuntimeKey).(*libpod.Runtime)
+	ctr, err := runtime.LookupContainer(name)
+	if err != nil {
+		utils.ContainerNotFound(w, name, err)
+		return
+	}
+
+	options := &handlers.UpdateEntities{Resources: &specs.LinuxResources{}}
+	if err := json.NewDecoder(r.Body).Decode(&options.Resources); err != nil {
+		utils.Error(w, http.StatusInternalServerError, fmt.Errorf("decode(): %w", err))
+		return
+	}
+	err = ctr.Update(options.Resources)
+	if err != nil {
+		utils.InternalServerError(w, err)
+		return
+	}
+	utils.WriteResponse(w, http.StatusCreated, ctr.ID())
+}
+
 func ShouldRestart(w http.ResponseWriter, r *http.Request) {
 	runtime := r.Context().Value(api.RuntimeKey).(*libpod.Runtime)
 	// Now use the ABI implementation to prevent us from having duplicate
diff --git a/pkg/api/handlers/swagger/responses.go b/pkg/api/handlers/swagger/responses.go
index 93a508b39..3de9b06e9 100644
--- a/pkg/api/handlers/swagger/responses.go
+++ b/pkg/api/handlers/swagger/responses.go
@@ -313,6 +313,11 @@ type containerCreateResponse struct {
 	Body entities.ContainerCreateResponse
 }
 
+type containerUpdateResponse struct {
+	// in:body
+	ID string
+}
+
 // Wait container
 // swagger:response
 type containerWaitResponse struct {
diff --git a/pkg/api/handlers/types.go b/pkg/api/handlers/types.go
index aab905878..bb416d9f4 100644
--- a/pkg/api/handlers/types.go
+++ b/pkg/api/handlers/types.go
@@ -11,6 +11,7 @@ import (
 	dockerContainer "github.com/docker/docker/api/types/container"
 	dockerNetwork "github.com/docker/docker/api/types/network"
 	"github.com/docker/go-connections/nat"
+	"github.com/opencontainers/runtime-spec/specs-go"
 )
 
 type AuthConfig struct {
@@ -64,6 +65,12 @@ type LibpodContainersRmReport struct {
 	RmError string `json:"Err,omitempty"`
 }
 
+// UpdateEntities used to wrap the oci resource spec in a swagger model
+// swagger:model
+type UpdateEntities struct {
+	Resources *specs.LinuxResources
+}
+
 type Info struct {
 	docker.Info
 	BuildahVersion     string
diff --git a/pkg/api/server/register_containers.go b/pkg/api/server/register_containers.go
index 8aba4ea05..41baf5418 100644
--- a/pkg/api/server/register_containers.go
+++ b/pkg/api/server/register_containers.go
@@ -1626,5 +1626,33 @@ func (s *APIServer) registerContainersHandlers(r *mux.Router) error {
 	//   500:
 	//     $ref: "#/responses/internalError"
 	r.HandleFunc(VersionedPath("/libpod/containers/{name}/rename"), s.APIHandler(compat.RenameContainer)).Methods(http.MethodPost)
+	// swagger:operation POST /libpod/containers/{name}/update libpod ContainerUpdateLibpod
+	// ---
+	// tags:
+	//   - containers
+	// summary: Update an existing containers cgroup configuration
+	// description: Update an existing containers cgroup configuration.
+	// parameters:
+	//  - in: path
+	//    name: name
+	//    type: string
+	//    required: true
+	//    description: Full or partial ID or full name of the container to update
+	//  - in: body
+	//    name: resources
+	//    description: attributes for updating the container
+	//    schema:
+	//      $ref: "#/definitions/UpdateEntities"
+	// produces:
+	// - application/json
+	// responses:
+	//   responses:
+	//     201:
+	//       $ref: "#/responses/containerUpdateResponse"
+	//   404:
+	//     $ref: "#/responses/containerNotFound"
+	//   500:
+	//     $ref: "#/responses/internalError"
+	r.HandleFunc(VersionedPath("/libpod/containers/{name}/update"), s.APIHandler(libpod.UpdateContainer)).Methods(http.MethodPost)
 	return nil
 }