package utils import ( "context" "fmt" "net/http" "strconv" "time" "github.com/containers/podman/v3/libpod/events" "github.com/containers/podman/v3/pkg/domain/entities" "github.com/containers/podman/v3/pkg/domain/infra/abi" "github.com/containers/podman/v3/pkg/api/handlers" "github.com/sirupsen/logrus" "github.com/containers/podman/v3/libpod/define" "github.com/containers/podman/v3/libpod" "github.com/gorilla/schema" "github.com/pkg/errors" ) type waitQueryDocker struct { Condition string `schema:"condition"` } type waitQueryLibpod struct { Interval string `schema:"interval"` Condition []define.ContainerStatus `schema:"condition"` } func WaitContainerDocker(w http.ResponseWriter, r *http.Request) { var err error ctx := r.Context() query := waitQueryDocker{} decoder := ctx.Value("decoder").(*schema.Decoder) if err = decoder.Decode(&query, r.URL.Query()); err != nil { Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String())) return } interval := time.Nanosecond condition := "not-running" if _, found := r.URL.Query()["condition"]; found { condition = query.Condition if !isValidDockerCondition(query.Condition) { BadRequest(w, "condition", condition, errors.New("not a valid docker condition")) return } } name := GetName(r) exists, err := containerExists(ctx, name) if err != nil { InternalServerError(w, err) return } if !exists { ContainerNotFound(w, name, define.ErrNoSuchCtr) return } // In docker compatibility mode we have to send headers in advance, // otherwise docker client would freeze. w.Header().Add("Content-Type", "application/json") w.WriteHeader(200) if flusher, ok := w.(http.Flusher); ok { flusher.Flush() } exitCode, err := waitDockerCondition(ctx, name, interval, condition) var errStruct *struct{ Message string } if err != nil { logrus.Errorf("error while waiting on condition: %q", err) errStruct = &struct { Message string }{ Message: err.Error(), } } responseData := handlers.ContainerWaitOKBody{ StatusCode: int(exitCode), Error: errStruct, } enc := json.NewEncoder(w) enc.SetEscapeHTML(true) err = enc.Encode(&responseData) if err != nil { logrus.Errorf("unable to write json: %q", err) } } func WaitContainerLibpod(w http.ResponseWriter, r *http.Request) { var ( err error interval = time.Millisecond * 250 conditions = []define.ContainerStatus{define.ContainerStateStopped, define.ContainerStateExited} ) decoder := r.Context().Value("decoder").(*schema.Decoder) query := waitQueryLibpod{} if err := decoder.Decode(&query, r.URL.Query()); err != nil { Error(w, "Something went wrong.", http.StatusBadRequest, errors.Wrapf(err, "failed to parse parameters for %s", r.URL.String())) return } if _, found := r.URL.Query()["interval"]; found { interval, err = time.ParseDuration(query.Interval) if err != nil { InternalServerError(w, err) return } } if _, found := r.URL.Query()["condition"]; found { if len(query.Condition) > 0 { conditions = query.Condition } } name := GetName(r) waitFn := createContainerWaitFn(r.Context(), name, interval) exitCode, err := waitFn(conditions...) if err != nil { if errors.Cause(err) == define.ErrNoSuchCtr { ContainerNotFound(w, name, err) return } InternalServerError(w, err) return } WriteResponse(w, http.StatusOK, strconv.Itoa(int(exitCode))) } type containerWaitFn func(conditions ...define.ContainerStatus) (int32, error) func createContainerWaitFn(ctx context.Context, containerName string, interval time.Duration) containerWaitFn { runtime := ctx.Value("runtime").(*libpod.Runtime) var containerEngine entities.ContainerEngine = &abi.ContainerEngine{Libpod: runtime} return func(conditions ...define.ContainerStatus) (int32, error) { opts := entities.WaitOptions{ Condition: conditions, Interval: interval, } ctrWaitReport, err := containerEngine.ContainerWait(ctx, []string{containerName}, opts) if err != nil { return -1, err } if len(ctrWaitReport) != 1 { return -1, fmt.Errorf("the ContainerWait() function returned unexpected count of reports: %d", len(ctrWaitReport)) } return ctrWaitReport[0].ExitCode, ctrWaitReport[0].Error } } func isValidDockerCondition(cond string) bool { switch cond { case "next-exit", "removed", "not-running", "": return true } return false } func waitDockerCondition(ctx context.Context, containerName string, interval time.Duration, dockerCondition string) (int32, error) { containerWait := createContainerWaitFn(ctx, containerName, interval) var err error var code int32 switch dockerCondition { case "next-exit": code, err = waitNextExit(ctx, containerName) case "removed": code, err = waitRemoved(containerWait) case "not-running", "": code, err = waitNotRunning(containerWait) default: panic("not a valid docker condition") } return code, err } var notRunningStates = []define.ContainerStatus{ define.ContainerStateCreated, define.ContainerStateRemoving, define.ContainerStateStopped, define.ContainerStateExited, define.ContainerStateConfigured, } func waitRemoved(ctrWait containerWaitFn) (int32, error) { code, err := ctrWait(define.ContainerStateUnknown) if err != nil && errors.Cause(err) == define.ErrNoSuchCtr { return code, nil } return code, err } func waitNextExit(ctx context.Context, containerName string) (int32, error) { runtime := ctx.Value("runtime").(*libpod.Runtime) containerEngine := &abi.ContainerEngine{Libpod: runtime} eventChannel := make(chan *events.Event) errChannel := make(chan error) opts := entities.EventsOptions{ EventChan: eventChannel, Filter: []string{"event=died", fmt.Sprintf("container=%s", containerName)}, Stream: true, } // ctx is used to cancel event watching goroutine ctx, cancel := context.WithCancel(ctx) defer cancel() go func() { errChannel <- containerEngine.Events(ctx, opts) }() evt, ok := <-eventChannel if ok { return int32(evt.ContainerExitCode), nil } // if ok == false then containerEngine.Events() has exited // it may happen if request was canceled (e.g. client closed connection prematurely) or // the server is in process of shutting down return -1, <-errChannel } func waitNotRunning(ctrWait containerWaitFn) (int32, error) { return ctrWait(notRunningStates...) } func containerExists(ctx context.Context, name string) (bool, error) { runtime := ctx.Value("runtime").(*libpod.Runtime) var containerEngine entities.ContainerEngine = &abi.ContainerEngine{Libpod: runtime} var ctrExistsOpts entities.ContainerExistsOptions ctrExistRep, err := containerEngine.ContainerExists(ctx, name, ctrExistsOpts) if err != nil { return false, err } return ctrExistRep.Value, nil }