lcitool container: Add "build" subcommand

This adds the "build" subcommand which is used to
build container image from args.projects and
args.target.

The Dockerfile string generated from using the
`DockerfileFormatter` class is copied to a temporary file
which is passed to the build command.

Tags are generated by prefixing the target name with
"lcitool.", e.g "lcitool.fedora-36" to prevent trashing
the output of "podman images" with incomprehensible tags.

If an image is present, it is removed before starting another
build to ensure the image is built from scratch.

Ensure that (--target & --projects) arguments are passed with
"build" subcommand.

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

2 files changed, 63 insertions, 0 deletions

diff --git a/lcitool/application.py b/lcitool/application.py
index 5b12d18..c5bbbab 100644
--- a/lcitool/application.py
+++ b/lcitool/application.py
@@ -6,9 +6,11 @@
 
 import logging
 import sys
+import textwrap
 
 from pathlib import Path
 from pkg_resources import resource_filename
+from tempfile import TemporaryDirectory, NamedTemporaryFile
 
 from lcitool import util, LcitoolError
 from lcitool.config import Config
@@ -326,6 +328,48 @@ class Application:
         else:
             print("No engine available")
 
+    def _action_container_build(self, args):
+        self._entrypoint_debug(args)
+
+        params = {}
+        client = self._get_client(args.engine)
+
+        container_tempdir = TemporaryDirectory(prefix="container",
+                                               dir=util.get_temp_dir())
+        params["tempdir"] = container_tempdir.name
+
+        tag = f"lcitool.{args.target}"
+
+        # remove image and prepare to build a new one.
+        client.rmi(tag)
+
+        targets = Targets()
+        packages = Packages()
+        projects = Projects()
+        projects_expanded = projects.expand_names(args.projects)
+        target = BuildTarget(targets, packages, args.target, args.cross_arch)
+
+        _file = None
+        file_content = DockerfileFormatter(projects).format(
+            target,
+            projects_expanded
+        )
+        with NamedTemporaryFile("w",
+                                delete=False,
+                                dir=params["tempdir"]) as fd:
+            fd.write(textwrap.dedent(file_content))
+            _file = fd.name
+
+        log.debug(f"Generated dockerfile copied to {_file}")
+
+        try:
+            client.build(tag=tag, filepath=_file, **params)
+        except ContainerError as ex:
+            raise ApplicationError(ex.message)
+
+        log.debug(f"Generated image tag --> {tag}")
+        print(f"Image '{tag}' successfully built.")
+
     def run(self, args):
         try:
             util.set_extra_data_dir(args.data_dir)
diff --git a/lcitool/commandline.py b/lcitool/commandline.py
index 8bd60c6..9e69c49 100644
--- a/lcitool/commandline.py
+++ b/lcitool/commandline.py
@@ -298,6 +298,14 @@ class CommandLine:
         )
         container_engineparser.set_defaults(func=Application._action_list_engines)
 
+        build_containerparser = containersubparser.add_parser(
+            "build",
+            help="Build container image",
+            parents=[installtargetopt, container_projectopt, engineopt,
+                     crossarchopt],
+        )
+        build_containerparser.set_defaults(func=Application._action_container_build)
+
     # Validate "container" args
     def _validate(self, args):
         """
@@ -308,6 +316,17 @@ class CommandLine:
         :return: args.
         """
 
+        if vars(args).get("container") \
+                and args.container in ["build", "run", "shell"]:
+
+            # Ensure that (--target & --projects) argument are passed with
+            # "build" subcommand.
+            if args.container == "build":
+                if args.projects and args.target:
+                    return args
+                else:
+                    log.error("--target and --projects are required")
+                    sys.exit(1)
         return args
 
     def parse(self):