lcitool container: Add "engines" subcommand

This adds the "engines" container subcommand
which is used to list all the available and
usable engines.

It allows users to decide on the engine to
select when spinning up containers and/or
building images.

Signed-off-by: Abdulwasiu Apalowo <abdulwasiuapalowo@gmail.com>

2 files changed, 18 insertions, 0 deletions

diff --git a/lcitool/application.py b/lcitool/application.py
index 93af712..5b12d18 100644
--- a/lcitool/application.py
+++ b/lcitool/application.py
@@ -18,6 +18,7 @@ from lcitool.projects import Projects
 from lcitool.targets import Targets, BuildTarget
 from lcitool.formatters import DockerfileFormatter, ShellVariablesFormatter, JSONVariablesFormatter, ShellBuildEnvFormatter
 from lcitool.manifest import Manifest
+from lcitool.containers import Docker, Podman, ContainerError
 
 
 log = logging.getLogger(__name__)
@@ -314,6 +315,17 @@ class Application:
 
         return client
 
+    def _action_list_engines(self, args):
+        engines = []
+        for engine in [Podman(), Docker()]:
+            if engine.available:
+                engines.append(engine.engine)
+
+        if engines:
+            print("\n".join(engines))
+        else:
+            print("No engine available")
+
     def run(self, args):
         try:
             util.set_extra_data_dir(args.data_dir)
diff --git a/lcitool/commandline.py b/lcitool/commandline.py
index 164888b..8bd60c6 100644
--- a/lcitool/commandline.py
+++ b/lcitool/commandline.py
@@ -292,6 +292,12 @@ class CommandLine:
                                                              dest='container')
         containersubparser.required = True
 
+        container_engineparser = containersubparser.add_parser(
+            "engines",
+            help="List available container engines",
+        )
+        container_engineparser.set_defaults(func=Application._action_list_engines)
+
     # Validate "container" args
     def _validate(self, args):
         """