From 118e78c5d69caade9e69a7f9d57dc53eee1840db Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Tue, 4 Feb 2020 16:56:07 -0500 Subject: Add structure for new exec session tracking to DB As part of the rework of exec sessions, we need to address them independently of containers. In the new API, we need to be able to fetch them by their ID, regardless of what container they are associated with. Unfortunately, our existing exec sessions are tied to individual containers; there's no way to tell what container a session belongs to and retrieve it without getting every exec session for every container. This adds a pointer to the container an exec session is associated with to the database. The sessions themselves are still stored in the container. Exec-related APIs have been restructured to work with the new database representation. The originally monolithic API has been split into a number of smaller calls to allow more fine-grained control of lifecycle. Support for legacy exec sessions has been retained, but in a deprecated fashion; we should remove this in a few releases. Signed-off-by: Matthew Heon --- libpod/container_exec.go | 769 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 769 insertions(+) create mode 100644 libpod/container_exec.go (limited to 'libpod/container_exec.go') diff --git a/libpod/container_exec.go b/libpod/container_exec.go new file mode 100644 index 000000000..8907f9917 --- /dev/null +++ b/libpod/container_exec.go @@ -0,0 +1,769 @@ +package libpod + +import ( + "io/ioutil" + "os" + "path/filepath" + "strconv" + "time" + + "github.com/containers/common/pkg/capabilities" + "github.com/containers/libpod/libpod/define" + "github.com/containers/libpod/libpod/events" + "github.com/containers/storage/pkg/stringid" + "github.com/pkg/errors" + "github.com/sirupsen/logrus" + "k8s.io/client-go/tools/remotecommand" +) + +// ExecConfig contains the configuration of an exec session +type ExecConfig struct { + // Command the the command that will be invoked in the exec session. + // Must not be empty. + Command []string `json:"command"` + // Terminal is whether the exec session will allocate a pseudoterminal. + Terminal bool `json:"terminal,omitempty"` + // AttachStdin is whether the STDIN stream will be forwarded to the exec + // session's first process when attaching. Only available if Terminal is + // false. + AttachStdin bool `json:"attachStdin,omitempty"` + // AttachStdout is whether the STDOUT stream will be forwarded to the + // exec session's first process when attaching. Only available if + // Terminal is false. + AttachStdout bool `json:"attachStdout,omitempty"` + // AttachStderr is whether the STDERR stream will be forwarded to the + // exec session's first process when attaching. Only available if + // Terminal is false. + AttachStderr bool `json:"attachStderr,omitempty"` + // DetachKeys are keys that will be used to detach from the exec + // session. Here, nil will use the default detach keys, where a pointer + // to the empty string ("") will disable detaching via detach keys. + DetachKeys *string `json:"detachKeys,omitempty"` + // Environment is a set of environment variables that will be set for + // the first process started by the exec session. + Environment map[string]string `json:"environment,omitempty"` + // Privileged is whether the exec session will be privileged - that is, + // will be granted additional capabilities. + Privileged bool `json:"privileged,omitempty"` + // User is the user the exec session will be run as. + // If set to "" the exec session will be started as the same user the + // container was started as. + User string `json:"user,omitempty"` + // WorkDir is the working directory for the first process that will be + // launched by the exec session. + // If set to "" the exec session will be started in / within the + // container. + WorkDir string `json:"workDir,omitempty"` + // PreserveFDs indicates that a number of extra FDs from the process + // running libpod will be passed into the container. These are assumed + // to begin at 3 (immediately after the standard streams). The number + // given is the number that will be passed into the exec session, + // starting at 3. + PreserveFDs uint `json:"preserveFds,omitempty"` +} + +// ExecSession contains information on a single exec session attached to a given +// container. +type ExecSession struct { + // Id is the ID of the exec session. + // Named somewhat strangely to not conflict with ID(). + Id string `json:"id"` + // ContainerId is the ID of the container this exec session belongs to. + // Named somewhat strangely to not conflict with ContainerID(). + ContainerId string `json:"containerId"` + + // State is the state of the exec session. + State define.ContainerExecStatus `json:"state"` + // PID is the PID of the process created by the exec session. + PID int `json:"pid,omitempty"` + // ExitCode is the exit code of the exec session, if it has exited. + ExitCode int `json:"exitCode,omitempty"` + + // Config is the configuration of this exec session. + // Cannot be empty. + Config *ExecConfig `json:"config"` +} + +// ID returns the ID of an exec session. +func (e *ExecSession) ID() string { + return e.Id +} + +// ContainerID returns the ID of the container this exec session was started in. +func (e *ExecSession) ContainerID() string { + return e.ContainerId +} + +// legacyExecSession contains information on an active exec session. It is a +// holdover from a previous Podman version and is DEPRECATED. +type legacyExecSession struct { + ID string `json:"id"` + Command []string `json:"command"` + PID int `json:"pid"` +} + +// ExecCreate creates a new exec session for the container. +// The session is not started. The ID of the new exec session will be returned. +func (c *Container) ExecCreate(config *ExecConfig) (string, error) { + if !c.batched { + c.lock.Lock() + defer c.lock.Unlock() + + if err := c.syncContainer(); err != nil { + return "", err + } + } + + // Verify our config + if config == nil { + return "", errors.Wrapf(define.ErrInvalidArg, "must provide a configuration to ExecCreate") + } + if len(config.Command) == 0 { + return "", errors.Wrapf(define.ErrInvalidArg, "must provide a non-empty command to start an exec session") + } + if config.Terminal && (config.AttachStdin || config.AttachStdout || config.AttachStderr) { + return "", errors.Wrapf(define.ErrInvalidArg, "cannot specify streams to attach to when exec session has a pseudoterminal") + } + + // Generate an ID for our new exec session + sessionID := stringid.GenerateNonCryptoID() + found := true + // This really ought to be a do-while, but Go doesn't have those... + for found { + found = false + for id := range c.state.ExecSessions { + if id == sessionID { + found = true + break + } + } + if found { + sessionID = stringid.GenerateNonCryptoID() + } + } + + // Make our new exec session + session := new(ExecSession) + session.Id = sessionID + session.ContainerId = c.ID() + session.State = define.ExecStateCreated + session.Config = new(ExecConfig) + if err := JSONDeepCopy(config, session.Config); err != nil { + return "", errors.Wrapf(err, "error copying exec configuration into exec session") + } + + if c.state.ExecSessions == nil { + c.state.ExecSessions = make(map[string]*ExecSession) + } + + // Need to add to container state and exec session registry + c.state.ExecSessions[session.ID()] = session + if err := c.save(); err != nil { + return "", err + } + if err := c.runtime.state.AddExecSession(c, session); err != nil { + return "", err + } + + logrus.Infof("Created exec session %s in container %s", session.ID(), c.ID()) + + return sessionID, nil +} + +// ExecStart starts an exec session in the container, but does not attach to it. +// Returns immediately upon starting the exec session. +func (c *Container) ExecStart(sessionID string) error { + // Will be implemented in part 2, migrating Start and implementing + // detached Start. + return define.ErrNotImplemented +} + +// ExecStartAndAttach starts and attaches to an exec session in a container. +// TODO: Should we include detach keys in the signature to allow override? +// TODO: How do we handle AttachStdin/AttachStdout/AttachStderr? +func (c *Container) ExecStartAndAttach(sessionID string, streams *AttachStreams) error { + if !c.batched { + c.lock.Lock() + defer c.lock.Unlock() + + if err := c.syncContainer(); err != nil { + return err + } + } + + session, ok := c.state.ExecSessions[sessionID] + if !ok { + return errors.Wrapf(define.ErrNoSuchExecSession, "container %s has no exec session with ID %s", c.ID(), sessionID) + } + + if session.State != define.ExecStateCreated { + return errors.Wrapf(define.ErrExecSessionStateInvalid, "can only start created exec sessions, while container %s session %s state is %q", c.ID(), session.ID(), session.State.String()) + } + + logrus.Infof("Going to start container %s exec session %s and attach to it", c.ID(), session.ID()) + + // TODO: check logic here - should we set Privileged if the container is + // privileged? + var capList []string + if session.Config.Privileged || c.config.Privileged { + capList = capabilities.AllCapabilities() + } + + user := c.config.User + if session.Config.User != "" { + user = session.Config.User + } + + if err := c.createExecBundle(session.ID()); err != nil { + return err + } + + opts := new(ExecOptions) + opts.Cmd = session.Config.Command + opts.CapAdd = capList + opts.Env = session.Config.Environment + opts.Terminal = session.Config.Terminal + opts.Cwd = session.Config.WorkDir + opts.User = user + opts.Streams = streams + opts.PreserveFDs = session.Config.PreserveFDs + opts.DetachKeys = session.Config.DetachKeys + + pid, attachChan, err := c.ociRuntime.ExecContainer(c, session.ID(), opts) + if err != nil { + return err + } + + c.newContainerEvent(events.Exec) + logrus.Debugf("Successfully started exec session %s in container %s", session.ID(), c.ID()) + + var lastErr error + + // Update and save session to reflect PID/running + session.PID = pid + session.State = define.ExecStateRunning + + if err := c.save(); err != nil { + lastErr = err + } + + // Unlock so other processes can use the container + if !c.batched { + c.lock.Unlock() + } + + tmpErr := <-attachChan + if lastErr != nil { + logrus.Errorf("Container %s exec session %s error: %v", c.ID(), session.ID(), lastErr) + } + lastErr = tmpErr + + exitCode, err := c.readExecExitCode(session.ID()) + if err != nil { + if lastErr != nil { + logrus.Errorf("Container %s exec session %s error: %v", c.ID(), session.ID(), lastErr) + } + lastErr = err + } + + logrus.Debugf("Container %s exec session %s completed with exit code %d", c.ID(), session.ID(), exitCode) + + // Lock again + if !c.batched { + c.lock.Lock() + } + + // Sync the container to pick up state changes + if err := c.syncContainer(); err != nil { + if lastErr != nil { + logrus.Errorf("Container %s exec session %s error: %v", c.ID(), session.ID(), lastErr) + } + return errors.Wrapf(err, "error syncing container %s state to remove exec session %s", c.ID(), session.ID()) + } + + // Update status + // Since we did a syncContainer, the old session has been overwritten. + // Grab a fresh one from the database. + session, ok = c.state.ExecSessions[sessionID] + if !ok { + // Exec session already removed. + logrus.Infof("Container %s exec session %s already removed from database", c.ID(), sessionID) + return nil + } + session.State = define.ExecStateStopped + session.ExitCode = exitCode + session.PID = 0 + + if err := c.save(); err != nil { + if lastErr != nil { + logrus.Errorf("Container %s exec session %s error: %v", c.ID(), session.ID(), lastErr) + } + lastErr = err + } + + // Clean up after ourselves + if err := c.cleanupExecBundle(session.ID()); err != nil { + if lastErr != nil { + logrus.Errorf("Container %s exec session %s error: %v", c.ID(), session.ID(), lastErr) + } + lastErr = err + } + + return lastErr +} + +// ExecHTTPStartAndAttach starts and performs an HTTP attach to an exec session. +func (c *Container) ExecHTTPStartAndAttach(sessionID string) error { + // Will be implemented in part 2, migrating Start. + return define.ErrNotImplemented +} + +// ExecStop stops an exec session in the container. +// If a timeout is provided, it will be used; otherwise, the timeout will +// default to the stop timeout of the container. +// Cleanup will be invoked automatically once the session is stopped. +func (c *Container) ExecStop(sessionID string, timeout *uint) error { + if !c.batched { + c.lock.Lock() + defer c.lock.Unlock() + + if err := c.syncContainer(); err != nil { + return err + } + } + + session, ok := c.state.ExecSessions[sessionID] + if !ok { + return errors.Wrapf(define.ErrNoSuchExecSession, "container %s has no exec session with ID %s", c.ID(), sessionID) + } + + if session.State != define.ExecStateRunning { + return errors.Wrapf(define.ErrExecSessionStateInvalid, "container %s exec session %s is %q, can only stop running sessions", c.ID(), session.ID(), session.State.String()) + } + + logrus.Infof("Stopping container %s exec session %s", c.ID(), session.ID()) + + finalTimeout := c.StopTimeout() + if timeout != nil { + finalTimeout = *timeout + } + + // Stop the session + if err := c.ociRuntime.ExecStopContainer(c, session.ID(), finalTimeout); err != nil { + return err + } + + var cleanupErr error + + // Retrieve exit code and update status + exitCode, err := c.readExecExitCode(session.ID()) + if err != nil { + cleanupErr = err + } + session.ExitCode = exitCode + session.PID = 0 + session.State = define.ExecStateStopped + + if err := c.save(); err != nil { + if cleanupErr != nil { + logrus.Errorf("Error stopping container %s exec session %s: %v", c.ID(), session.ID(), cleanupErr) + } + cleanupErr = err + } + + if err := c.cleanupExecBundle(session.ID()); err != nil { + if cleanupErr != nil { + logrus.Errorf("Error stopping container %s exec session %s: %v", c.ID(), session.ID(), cleanupErr) + } + cleanupErr = err + } + + return cleanupErr +} + +// ExecCleanup cleans up an exec session in the container, removing temporary +// files associated with it. +func (c *Container) ExecCleanup(sessionID string) error { + if !c.batched { + c.lock.Lock() + defer c.lock.Unlock() + + if err := c.syncContainer(); err != nil { + return err + } + } + + session, ok := c.state.ExecSessions[sessionID] + if !ok { + return errors.Wrapf(define.ErrNoSuchExecSession, "container %s has no exec session with ID %s", c.ID(), sessionID) + } + + if session.State == define.ExecStateRunning { + return errors.Wrapf(define.ErrExecSessionStateInvalid, "cannot clean up container %s exec session %s as it is running", c.ID(), session.ID()) + } + + logrus.Infof("Cleaning up container %s exec session %s", c.ID(), session.ID()) + + return c.cleanupExecBundle(session.ID()) +} + +// ExecRemove removes an exec session in the container. +// If force is given, the session will be stopped first if it is running. +func (c *Container) ExecRemove(sessionID string, force bool) error { + if !c.batched { + c.lock.Lock() + defer c.lock.Unlock() + + if err := c.syncContainer(); err != nil { + return err + } + } + + session, ok := c.state.ExecSessions[sessionID] + if !ok { + return errors.Wrapf(define.ErrNoSuchExecSession, "container %s has no exec session with ID %s", c.ID(), sessionID) + } + + logrus.Infof("Removing container %s exec session %s", c.ID(), session.ID()) + + // Update status of exec session if running, so we cna check if it + // stopped in the meantime. + if session.State == define.ExecStateRunning { + stopped, err := c.ociRuntime.ExecUpdateStatus(c, session.ID()) + if err != nil { + return err + } + if stopped { + session.State = define.ExecStateStopped + // TODO: should we retrieve exit code here? + // TODO: Might be worth saving state here. + } + } + + if session.State == define.ExecStateRunning { + if !force { + return errors.Wrapf(define.ErrExecSessionStateInvalid, "container %s exec session %s is still running, cannot remove", c.ID(), session.ID()) + } + + // Stop the session + if err := c.ociRuntime.ExecStopContainer(c, session.ID(), c.StopTimeout()); err != nil { + return err + } + + if err := c.cleanupExecBundle(session.ID()); err != nil { + return err + } + } + + // First remove exec session from DB. + if err := c.runtime.state.RemoveExecSession(session); err != nil { + return err + } + // Next, remove it from the container and save state + delete(c.state.ExecSessions, sessionID) + if err := c.save(); err != nil { + return err + } + + logrus.Debugf("Successfully removed container %s exec session %s", c.ID(), session.ID()) + + return nil +} + +// ExecResize resizes the TTY of the given exec session. Only available if the +// exec session created a TTY. +func (c *Container) ExecResize(sessionID string, newSize remotecommand.TerminalSize) error { + if !c.batched { + c.lock.Lock() + defer c.lock.Unlock() + + if err := c.syncContainer(); err != nil { + return err + } + } + + session, ok := c.state.ExecSessions[sessionID] + if !ok { + return errors.Wrapf(define.ErrNoSuchExecSession, "container %s has no exec session with ID %s", c.ID(), sessionID) + } + + logrus.Infof("Removing container %s exec session %s", c.ID(), session.ID()) + + if session.State != define.ExecStateRunning { + return errors.Wrapf(define.ErrExecSessionStateInvalid, "cannot resize container %s exec session %s as it is not running", c.ID(), session.ID()) + } + + return c.ociRuntime.ExecAttachResize(c, sessionID, newSize) +} + +// Exec emulates the old Libpod exec API, providing a single call to create, +// run, and remove an exec session. Returns exit code and error. Exit code is +// not guaranteed to be set sanely if error is not nil. +func (c *Container) Exec(config *ExecConfig, streams *AttachStreams, resize <-chan remotecommand.TerminalSize) (int, error) { + sessionID, err := c.ExecCreate(config) + if err != nil { + return -1, err + } + if err := c.ExecStartAndAttach(sessionID, streams); err != nil { + return -1, err + } + + // Start resizing if we have a resize channel. + // This goroutine may likely leak, given that we cannot close it here. + // Not a big deal, since it should run for as long as the Podman process + // does. Could be a big deal for `podman service` but we don't need this + // API there. + // TODO: Refactor so this is closed here, before we remove the exec + // session. + if resize != nil { + go func() { + for resizeRequest := range resize { + if err := c.ExecResize(sessionID, resizeRequest); err != nil { + // Assume the exec session went down. + logrus.Warnf("Error resizing exec session %s: %v", sessionID, err) + return + } + } + }() + } + + session, err := c.ExecSession(sessionID) + if err != nil { + return -1, err + } + exitCode := session.ExitCode + if err := c.ExecRemove(sessionID, false); err != nil { + return -1, err + } + + if exitCode != 0 { + return exitCode, errors.Wrapf(define.ErrOCIRuntime, "exec session exited with non-zero exit code %d", exitCode) + } + + return exitCode, nil +} + +// cleanup an exec session after its done +func (c *Container) cleanupExecBundle(sessionID string) error { + if err := os.RemoveAll(c.execBundlePath(sessionID)); err != nil && !os.IsNotExist(err) { + return err + } + + return c.ociRuntime.ExecContainerCleanup(c, sessionID) +} + +// the path to a containers exec session bundle +func (c *Container) execBundlePath(sessionID string) string { + return filepath.Join(c.bundlePath(), sessionID) +} + +// Get PID file path for a container's exec session +func (c *Container) execPidPath(sessionID string) string { + return filepath.Join(c.execBundlePath(sessionID), "exec_pid") +} + +// the log path for an exec session +func (c *Container) execLogPath(sessionID string) string { + return filepath.Join(c.execBundlePath(sessionID), "exec_log") +} + +// the socket conmon creates for an exec session +func (c *Container) execAttachSocketPath(sessionID string) (string, error) { + return c.ociRuntime.ExecAttachSocketPath(c, sessionID) +} + +// execExitFileDir gets the path to the container's exit file +func (c *Container) execExitFileDir(sessionID string) string { + return filepath.Join(c.execBundlePath(sessionID), "exit") +} + +// execOCILog returns the file path for the exec sessions oci log +func (c *Container) execOCILog(sessionID string) string { + if !c.ociRuntime.SupportsJSONErrors() { + return "" + } + return filepath.Join(c.execBundlePath(sessionID), "oci-log") +} + +// create a bundle path and associated files for an exec session +func (c *Container) createExecBundle(sessionID string) (err error) { + bundlePath := c.execBundlePath(sessionID) + if createErr := os.MkdirAll(bundlePath, execDirPermission); createErr != nil { + return createErr + } + defer func() { + if err != nil { + if err2 := os.RemoveAll(bundlePath); err != nil { + logrus.Warnf("error removing exec bundle after creation caused another error: %v", err2) + } + } + }() + if err2 := os.MkdirAll(c.execExitFileDir(sessionID), execDirPermission); err2 != nil { + // The directory is allowed to exist + if !os.IsExist(err2) { + err = errors.Wrapf(err2, "error creating OCI runtime exit file path %s", c.execExitFileDir(sessionID)) + } + } + return +} + +// readExecExitCode reads the exit file for an exec session and returns +// the exit code +func (c *Container) readExecExitCode(sessionID string) (int, error) { + exitFile := filepath.Join(c.execExitFileDir(sessionID), c.ID()) + chWait := make(chan error) + defer close(chWait) + + _, err := WaitForFile(exitFile, chWait, time.Second*5) + if err != nil { + return -1, err + } + ec, err := ioutil.ReadFile(exitFile) + if err != nil { + return -1, err + } + ecInt, err := strconv.Atoi(string(ec)) + if err != nil { + return -1, err + } + return ecInt, nil +} + +// getExecSessionPID gets the PID of an active exec session +func (c *Container) getExecSessionPID(sessionID string) (int, error) { + session, ok := c.state.ExecSessions[sessionID] + if ok { + return session.PID, nil + } + oldSession, ok := c.state.LegacyExecSessions[sessionID] + if ok { + return oldSession.PID, nil + } + + return -1, errors.Wrapf(define.ErrNoSuchExecSession, "no exec session with ID %s found in container %s", sessionID, c.ID()) +} + +// getKnownExecSessions gets a list of all exec sessions we think are running, +// but does not verify their current state. +// Please use getActiveExecSessions() outside of container_exec.go, as this +// function performs further checks to return an accurate list. +func (c *Container) getKnownExecSessions() []string { + knownSessions := []string{} + // First check legacy sessions. + // TODO: This is DEPRECATED and will be removed in a future major + // release. + for sessionID := range c.state.LegacyExecSessions { + knownSessions = append(knownSessions, sessionID) + } + // Next check new exec sessions, but only if in running state + for sessionID, session := range c.state.ExecSessions { + if session.State == define.ExecStateRunning { + knownSessions = append(knownSessions, sessionID) + } + } + + return knownSessions +} + +// getActiveExecSessions checks if there are any active exec sessions in the +// current container. Returns an array of active exec sessions. +// Will continue through errors where possible. +// Currently handles both new and legacy, deprecated exec sessions. +func (c *Container) getActiveExecSessions() ([]string, error) { + activeSessions := []string{} + knownSessions := c.getKnownExecSessions() + + // Instead of saving once per iteration, do it once at the end. + var lastErr error + needSave := false + for _, id := range knownSessions { + alive, err := c.ociRuntime.ExecUpdateStatus(c, id) + if err != nil { + if lastErr != nil { + logrus.Errorf("Error checking container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + continue + } + if !alive { + if err := c.cleanupExecBundle(id); err != nil { + if lastErr != nil { + logrus.Errorf("Error checking container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + } + + _, isLegacy := c.state.LegacyExecSessions[id] + if isLegacy { + delete(c.state.LegacyExecSessions, id) + needSave = true + } else { + session := c.state.ExecSessions[id] + exitCode, err := c.readExecExitCode(session.ID()) + if err != nil { + if lastErr != nil { + logrus.Errorf("Error checking container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + } + session.ExitCode = exitCode + session.PID = 0 + session.State = define.ExecStateStopped + + needSave = true + } + } else { + activeSessions = append(activeSessions, id) + } + } + if needSave { + if err := c.save(); err != nil { + if lastErr != nil { + logrus.Errorf("Error reaping exec sessions for container %s: %v", c.ID(), lastErr) + } + lastErr = err + } + } + + return activeSessions, lastErr +} + +// removeAllExecSessions stops and removes all the container's exec sessions +func (c *Container) removeAllExecSessions() error { + knownSessions := c.getKnownExecSessions() + + var lastErr error + for _, id := range knownSessions { + if err := c.ociRuntime.ExecStopContainer(c, id, c.StopTimeout()); err != nil { + if lastErr != nil { + logrus.Errorf("Error stopping container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + continue + } + + if err := c.cleanupExecBundle(id); err != nil { + if lastErr != nil { + logrus.Errorf("Error stopping container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + } + } + // Delete all exec sessions + if err := c.runtime.state.RemoveContainerExecSessions(c); err != nil { + if lastErr != nil { + logrus.Errorf("Error stopping container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + } + c.state.ExecSessions = nil + c.state.LegacyExecSessions = nil + if err := c.save(); err != nil { + if lastErr != nil { + logrus.Errorf("Error stopping container %s exec sessions: %v", c.ID(), lastErr) + } + lastErr = err + } + + return lastErr +} -- cgit v1.2.3-54-g00ecf From e89c6382ae26b6d611106360fdba4f3f304e5616 Mon Sep 17 00:00:00 2001 From: Matthew Heon Date: Sun, 15 Mar 2020 22:22:18 -0400 Subject: Add inspect for exec sessions This produces detailed information about the configuration of an exec session in a format suitable for the new HTTP API. Signed-off-by: Matthew Heon --- libpod/container_exec.go | 88 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 88 insertions(+) (limited to 'libpod/container_exec.go') diff --git a/libpod/container_exec.go b/libpod/container_exec.go index 8907f9917..7ed7a3343 100644 --- a/libpod/container_exec.go +++ b/libpod/container_exec.go @@ -94,6 +94,94 @@ func (e *ExecSession) ContainerID() string { return e.ContainerId } +// InspectExecSession contains information about a given exec session. +type InspectExecSession struct { + // CanRemove is legacy and used purely for compatibility reasons. + // Will always be set to true, unless the exec session is running. + CanRemove bool `json:"CanRemove"` + // ContainerID is the ID of the container this exec session is attached + // to. + ContainerID string `json:"ContainerID"` + // DetachKeys are the detach keys used by the exec session. + // If set to "" the default keys are being used. + // Will show "" if no detach keys are set. + DetachKeys string `json:"DetachKeys"` + // ExitCode is the exit code of the exec session. Will be set to 0 if + // the exec session has not yet exited. + ExitCode int `json:"ExitCode"` + // ID is the ID of the exec session. + ID string `json:"ID"` + // OpenStderr is whether the container's STDERR stream will be attached. + // Always set to true if the exec session created a TTY. + OpenStderr bool `json:"OpenStderr"` + // OpenStdin is whether the container's STDIN stream will be attached + // to. + OpenStdin bool `json:"OpenStdin"` + // OpenStdout is whether the container's STDOUT stream will be attached. + // Always set to true if the exec session created a TTY. + OpenStdout bool `json:"OpenStdout"` + // Running is whether the exec session is running. + Running bool `json:"Running"` + // Pid is the PID of the exec session's process. + // Will be set to 0 if the exec session is not running. + Pid int `json:"Pid"` + // ProcessConfig contains information about the exec session's process. + ProcessConfig *InspectExecProcess `json:"ProcessConfig"` +} + +// InspectExecProcess contains information about the process in a given exec +// session. +type InspectExecProcess struct { + // Arguments are the arguments to the entrypoint command of the exec + // session. + Arguments []string `json:"arguments"` + // Entrypoint is the entrypoint for the exec session (the command that + // will be executed in the container). + Entrypoint string `json:"entrypoint"` + // Privileged is whether the exec session will be started with elevated + // privileges. + Privileged bool `json:"privileged"` + // Tty is whether the exec session created a terminal. + Tty bool `json:"tty"` + // User is the user the exec session was started as. + User string `json:"user"` +} + +// Inspect inspects the given exec session and produces detailed output on its +// configuration and current state. +func (e *ExecSession) Inspect() (*InspectExecSession, error) { + if e.Config == nil { + return nil, errors.Wrapf(define.ErrInternal, "given exec session does not have a configuration block") + } + + output := new(InspectExecSession) + output.CanRemove = e.State != define.ExecStateRunning + output.ContainerID = e.ContainerId + if e.Config.DetachKeys != nil { + output.DetachKeys = *e.Config.DetachKeys + } + output.ExitCode = e.ExitCode + output.ID = e.Id + output.OpenStderr = e.Config.AttachStderr + output.OpenStdin = e.Config.AttachStdin + output.OpenStdout = e.Config.AttachStdout + output.Running = e.State == define.ExecStateRunning + output.Pid = e.PID + output.ProcessConfig = new(InspectExecProcess) + if len(e.Config.Command) > 0 { + output.ProcessConfig.Entrypoint = e.Config.Command[0] + if len(e.Config.Command) > 1 { + output.ProcessConfig.Arguments = make([]string, 0, len(e.Config.Command)-1) + output.ProcessConfig.Arguments = append(output.ProcessConfig.Arguments, e.Config.Command[1:]...) + } + } + output.ProcessConfig.Privileged = e.Config.Privileged + output.ProcessConfig.Tty = e.Config.Terminal + output.ProcessConfig.User = e.Config.User + + return output, nil +} + // legacyExecSession contains information on an active exec session. It is a // holdover from a previous Podman version and is DEPRECATED. type legacyExecSession struct { -- cgit v1.2.3-54-g00ecf