Support additional_contexts

Signed-off-by: Otto Liljalaakso <otto.liljalaakso@novatron.fi>

podman_compose.py

@@ -1464,6 +1464,12 @@ def normalize_service(service, sub_dir=""):
             if not context:
                 context = "."
             service["build"]["context"] = context
+    if "build" in service and "additional_contexts" in service["build"]:
+        if is_dict(build["additional_contexts"]):
+            new_additional_contexts = []
+            for k, v in build["additional_contexts"].items():
+                new_additional_contexts.append(f"{k}={v}")
+            build["additional_contexts"] = new_additional_contexts
     for key in ("command", "entrypoint"):
         if key in service:
             if is_str(service[key]):
@@ -2330,6 +2336,8 @@ async def build_one(compose, args, cnt):
         build_args.extend(get_secret_args(compose, cnt, secret, podman_is_building=True))
     for tag in build_desc.get("tags", []):
         build_args.extend(["-t", tag])
+    for additional_ctx in build_desc.get("additional_contexts", {}):
+        build_args.extend([f"--build-context={additional_ctx}"])
     if "target" in build_desc:
         build_args.extend(["--target", build_desc["target"]])
     container_to_ulimit_build_args(cnt, build_args)

pytests/test_normalize_service.py

@@ -20,6 +20,14 @@ class TestNormalizeService(unittest.TestCase):
             {"build": {"context": "./dir-1", "dockerfile": "dockerfile-1"}},
             {"build": {"context": "./dir-1", "dockerfile": "dockerfile-1"}},
         ),
+        (
+            {"build": {"additional_contexts": ["ctx=../ctx", "ctx2=../ctx2"]}},
+            {"build": {"additional_contexts": ["ctx=../ctx", "ctx2=../ctx2"]}},
+        ),
+        (
+            {"build": {"additional_contexts": {"ctx": "../ctx", "ctx2": "../ctx2"}}},
+            {"build": {"additional_contexts": ["ctx=../ctx", "ctx2=../ctx2"]}},
+        ),
     ])
     def test_simple(self, input, expected):
         self.assertEqual(normalize_service(input), expected)

tests/additional_contexts/README.md

@@ -0,0 +1,14 @@
+# Test podman-compose with build.additional_contexts
+
+```
+podman-compose build
+podman-compose up
+podman-compose down
+```
+
+expected output would be
+
+```
+[dict] | Data for dict
+[list] | Data for list
+```

tests/additional_contexts/data_for_dict/data.txt

@@ -0,0 +1 @@
+Data for dict

tests/additional_contexts/data_for_list/data.txt

@@ -0,0 +1 @@
+Data for list

tests/additional_contexts/project/Dockerfile

@@ -0,0 +1,3 @@
+FROM busybox
+COPY --from=data data.txt /data/data.txt
+CMD ["busybox", "cat", "/data/data.txt"]

tests/additional_contexts/project/docker-compose.yml

@@ -0,0 +1,12 @@
+version: "3.7"
+services:
+  dict:
+    build:
+      context: .
+      additional_contexts:
+        data: ../data_for_dict
+  list:
+    build:
+      context: .
+      additional_contexts:
+        - data=../data_for_list

tests/test_podman_compose_additional_contexts.py

@@ -0,0 +1,44 @@
+# SPDX-License-Identifier: GPL-2.0
+
+
+"""Test how additional contexts are passed to podman."""
+
+import os
+import subprocess
+import unittest
+
+from .test_podman_compose import podman_compose_path
+from .test_podman_compose import test_path
+
+
+def compose_yaml_path():
+    """ "Returns the path to the compose file used for this test module"""
+    return os.path.join(test_path(), "additional_contexts", "project")
+
+
+class TestComposeBuildAdditionalContexts(unittest.TestCase):
+    def test_build_additional_context(self):
+        """podman build should receive additional contexts as --build-context
+
+        See additional_context/project/docker-compose.yaml for context paths
+        """
+        cmd = (
+            "coverage",
+            "run",
+            podman_compose_path(),
+            "--dry-run",
+            "--verbose",
+            "-f",
+            os.path.join(compose_yaml_path(), "docker-compose.yml"),
+            "build",
+        )
+        p = subprocess.run(
+            cmd,
+            stdout=subprocess.PIPE,
+            check=False,
+            stderr=subprocess.STDOUT,
+            text=True,
+        )
+        self.assertEqual(p.returncode, 0)
+        self.assertIn("--build-context=data=../data_for_dict", p.stdout)
+        self.assertIn("--build-context=data=../data_for_list", p.stdout)