Add --requires flag to podman run/create

Podman has, for a long time, had an internal concept of
dependency management, used mainly to ensure that pod infra
containers are started before any other container in the pod. We
also have the ability to recursively start these dependencies,
which we use to ensure that `podman start` on a container in a
pod will not fail because the infra container is stopped. We have
not, however, exposed these via the command line until now.

Add a `--requires` flag to `podman run` and `podman create` to
allow users to manually specify dependency containers. These
containers must be running before the container will start. Also,
make recursive starting with `podman start` default so we can
start these containers and their dependencies easily.

Fixes #9250

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

3 files changed, 7 insertions, 3 deletions

diff --git a/libpod/boltdb_state_internal.go b/libpod/boltdb_state_internal.go
index d4994334f..f63876c14 100644
--- a/libpod/boltdb_state_internal.go
+++ b/libpod/boltdb_state_internal.go
@@ -919,7 +919,7 @@ func (s *BoltState) removeContainer(ctr *Container, pod *Pod, tx *bolt.Tx) error
 		return err
 	}
 	if len(deps) != 0 {
-		return errors.Wrapf(define.ErrCtrExists, "container %s is a dependency of the following containers: %s", ctr.ID(), strings.Join(deps, ", "))
+		return errors.Wrapf(define.ErrDepExists, "container %s is a dependency of the following containers: %s", ctr.ID(), strings.Join(deps, ", "))
 	}
 
 	if err := ctrBucket.DeleteBucket(ctrID); err != nil {
diff --git a/libpod/define/errors.go b/libpod/define/errors.go
index 2e85454b2..e19ac6a27 100644
--- a/libpod/define/errors.go
+++ b/libpod/define/errors.go
@@ -31,6 +31,10 @@ var (
 	// not exist.
 	ErrNoSuchExecSession = errors.New("no such exec session")
 
+	// ErrDepExists indicates that the current object has dependencies and
+	// cannot be removed before them.
+	ErrDepExists = errors.New("dependency exists")
+
 	// ErrNoAliases indicates that the container does not have any network
 	// aliases.
 	ErrNoAliases = errors.New("no aliases for container")
diff --git a/libpod/in_memory_state.go b/libpod/in_memory_state.go
index 3875878ed..df45f8e73 100644
--- a/libpod/in_memory_state.go
+++ b/libpod/in_memory_state.go
@@ -391,7 +391,7 @@ func (s *InMemoryState) RemoveContainer(ctr *Container) error {
 	deps, ok := s.ctrDepends[ctr.ID()]
 	if ok && len(deps) != 0 {
 		depsStr := strings.Join(deps, ", ")
-		return errors.Wrapf(define.ErrCtrExists, "the following containers depend on container %s: %s", ctr.ID(), depsStr)
+		return errors.Wrapf(define.ErrDepExists, "the following containers depend on container %s: %s", ctr.ID(), depsStr)
 	}
 
 	// Ensure we don't have active exec sessions
@@ -1497,7 +1497,7 @@ func (s *InMemoryState) RemoveContainerFromPod(pod *Pod, ctr *Container) error {
 	deps, ok := s.ctrDepends[ctr.ID()]
 	if ok && len(deps) != 0 {
 		depsStr := strings.Join(deps, ", ")
-		return errors.Wrapf(define.ErrCtrExists, "the following containers depend on container %s: %s", ctr.ID(), depsStr)
+		return errors.Wrapf(define.ErrDepExists, "the following containers depend on container %s: %s", ctr.ID(), depsStr)
 	}
 
 	// Ensure we don't have active exec sessions