add support of platforms in build section

Signed-off-by: Guillaume Lours <guillaume.lours@docker.com>

pkg/e2e/build_test.go

@@ -243,3 +243,73 @@ func TestBuildImageDependencies(t *testing.T) {
 		t.Skip("See https://github.com/docker/compose/issues/9232")
 	})
 }
+
+func TestBuildPlatformsWithCorrectBuildxConfig(t *testing.T) {
+	c := NewParallelCLI(t)
+
+	// declare builder
+	result := c.RunDockerCmd(t, "buildx", "create", "--name", "build-platform", "--use", "--bootstrap", "--driver-opt",
+		"network=host", "--buildkitd-flags", "--allow-insecure-entitlement network.host")
+	assert.NilError(t, result.Error)
+
+	// start local registry
+	result = c.RunDockerCmd(t, "run", "-d", "-p", "5001:5000", "--restart=always",
+		"--name", "registry", "registry:2")
+	assert.NilError(t, result.Error)
+
+	t.Cleanup(func() {
+		_ = c.RunDockerCmd(t, "buildx", "rm", "-f", "build-platform")
+		_ = c.RunDockerCmd(t, "rm", "-f", "registry")
+	})
+
+	t.Run("platform not supported by builder", func(t *testing.T) {
+		res := c.RunDockerComposeCmdNoCheck(t, "--project-directory", "fixtures/build-test/platforms",
+			"-f", "fixtures/build-test/platforms/compose-unsupported-platform.yml", "build")
+		res.Assert(t, icmd.Expected{
+			ExitCode: 17,
+			Err:      "failed to solve: alpine: no match for platform in",
+		})
+	})
+
+	t.Run("multi-arch build ok", func(t *testing.T) {
+		res := c.RunDockerComposeCmdNoCheck(t, "--project-directory", "fixtures/build-test/platforms", "build")
+		assert.NilError(t, res.Error, res.Stderr())
+		res = c.RunDockerCmd(t, "manifest", "inspect", "--insecure", "localhost:5001/build-test-platform:test")
+		res.Assert(t, icmd.Expected{Out: `"architecture": "amd64",`})
+		res.Assert(t, icmd.Expected{Out: `"architecture": "arm64",`})
+
+	})
+}
+
+func TestBuildPlatformsStandardErrors(t *testing.T) {
+	c := NewParallelCLI(t)
+
+	t.Run("no platform support with Classic Builder", func(t *testing.T) {
+		cmd := c.NewDockerComposeCmd(t, "--project-directory", "fixtures/build-test/platforms", "build")
+
+		res := icmd.RunCmd(cmd, func(cmd *icmd.Cmd) {
+			cmd.Env = append(cmd.Env, "DOCKER_BUILDKIT=0")
+		})
+		res.Assert(t, icmd.Expected{
+			ExitCode: 1,
+			Err:      "this builder doesn't support multi-arch build, set DOCKER_BUILDKIT=1 to use multi-arch builder",
+		})
+	})
+
+	t.Run("builder does not support multi-arch", func(t *testing.T) {
+		res := c.RunDockerComposeCmdNoCheck(t, "--project-directory", "fixtures/build-test/platforms", "build")
+		res.Assert(t, icmd.Expected{
+			ExitCode: 17,
+			Err:      `multiple platforms feature is currently not supported for docker driver. Please switch to a different driver (eg. "docker buildx create --use")`,
+		})
+	})
+
+	t.Run("service platform not defined in platforms build section", func(t *testing.T) {
+		res := c.RunDockerComposeCmdNoCheck(t, "--project-directory", "fixtures/build-test/platforms",
+			"-f", "fixtures/build-test/platforms/compose-service-platform-not-in-build-platforms.yaml", "build")
+		res.Assert(t, icmd.Expected{
+			ExitCode: 1,
+			Err:      `service.platform should be part of the service.build.platforms: "linux/riscv64"`,
+		})
+	})
+}

pkg/e2e/fixtures/build-test/platforms/Dockerfile

@@ -0,0 +1,17 @@
+#   Copyright 2020 Docker Compose CLI authors
+
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+
+#       http://www.apache.org/licenses/LICENSE-2.0
+
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+
+FROM alpine
+
+RUN echo "SUCCESS"

pkg/e2e/fixtures/build-test/platforms/compose-service-platform-not-in-build-platforms.yaml

@@ -0,0 +1,9 @@
+services:
+  platforms:
+    image: build-test-platform:test
+    platform: linux/riscv64
+    build:
+      context: .
+      platforms:
+        - linux/amd64
+        - linux/arm64

pkg/e2e/fixtures/build-test/platforms/compose-unsupported-platform.yml

@@ -0,0 +1,8 @@
+services:
+  platforms:
+    image: build-test-platform:test
+    build:
+      context: .
+      platforms:
+        - unsupported/unsupported
+        - linux/amd64

pkg/e2e/fixtures/build-test/platforms/compose.yaml

@@ -0,0 +1,10 @@
+services:
+  platforms:
+    image: localhost:5001/build-test-platform:test
+    platform: linux/amd64
+    build:
+      context: .
+      platforms:
+        - linux/amd64
+        - linux/arm64
+