Populate ExecSession with all required fields

As part of the rework of exec sessions, we want to split Create
and Start - and, as a result, we need to keep everything needed
to start exec sessions in the struct, not just the bare minimum
for tracking running ones.

Signed-off-by: Matthew Heon <matthew.heon@pm.me>

libpod/container.go

@@ -216,9 +216,50 @@ type ContainerState struct {
 
 // ExecSession contains information on an active exec session
 type ExecSession struct {
-	ID      string   `json:"id"`
+	// ID is the ID of the exec session.
+	ID string `json:"id"`
+	// Command the the command that will be invoked in the exec session.
 	Command []string `json:"command"`
-	PID     int      `json:"pid"`
+	// 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"`
+
+	// 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.
+	User string `json:"user,omitempty"`
+	// WorkDir is the working directory for the first process that will be
+	// launched by the exec session.
+	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"`
 }
 
 // ContainerConfig contains all information that was used to create the

libpod/define/containerstate.go

@@ -78,3 +78,37 @@ func StringToContainerStatus(status string) (ContainerStatus, error) {
 		return ContainerStateUnknown, errors.Wrapf(ErrInvalidArg, "unknown container state: %s", status)
 	}
 }
+
+// ContainerExecStatus is the status of an exec session within a container.
+type ContainerExecStatus int
+
+const (
+	// ExecStateUnknown indicates that the state of the exec session is not
+	// known.
+	ExecStateUnknown ContainerExecStatus = iota
+	// ExecStateCreated indicates that the exec session has been created but
+	// not yet started
+	ExecStateCreated ContainerExecStatus = iota
+	// ExecStateRunning indicates that the exec session has been started but
+	// has not yet exited.
+	ExecStateRunning ContainerExecStatus = iota
+	// ExecStateStopped indicates that the exec session has stopped and is
+	// no longer running.
+	ExecStateStopped ContainerExecStatus = iota
+)
+
+// String returns a string representation of a given exec state.
+func (s ContainerExecStatus) String() string {
+	switch s {
+	case ExecStateUnknown:
+		return "unknown"
+	case ExecStateCreated:
+		return "created"
+	case ExecStateRunning:
+		return "running"
+	case ExecStateStopped:
+		return "stopped"
+	default:
+		return "bad state"
+	}
+}