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 <matthew.heon@pm.me>

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 "<none>" 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 {