Refactor skaffold init for more flexible builder detection

pkg/skaffold/docker/docker_init.go

@@ -0,0 +1,99 @@
+/*
+Copyright 2019 The Skaffold 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.
+*/
+
+package docker
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/constants"
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest"
+	"github.com/moby/buildkit/frontend/dockerfile/command"
+	"github.com/moby/buildkit/frontend/dockerfile/parser"
+	"github.com/sirupsen/logrus"
+)
+
+// For testing
+var (
+	ValidateDockerfileFunc = ValidateDockerfile
+)
+
+// Docker is the path to a dockerfile. Implements the InitBuilder interface.
+type Docker string
+
+// Name returns the name of the builder, "Docker"
+func (d Docker) Name() string {
+	return "Docker"
+}
+
+// Describe returns the initBuilder's string representation, used when prompting the user to choose a builder.
+func (d Docker) Describe() string {
+	return fmt.Sprintf("%s (%s)", d.Name(), d)
+}
+
+// CreateArtifact creates an Artifact to be included in the generated Build Config
+func (d Docker) CreateArtifact(manifestImage string) *latest.Artifact {
+	path := string(d)
+	workspace := filepath.Dir(path)
+	a := &latest.Artifact{ImageName: manifestImage}
+	if workspace != "." {
+		a.Workspace = workspace
+	}
+	if filepath.Base(path) != constants.DefaultDockerfilePath {
+		a.ArtifactType = latest.ArtifactType{
+			DockerArtifact: &latest.DockerArtifact{DockerfilePath: path},
+		}
+	}
+
+	return a
+}
+
+// ConfiguredImage returns the target image configured by the builder, or an empty string if no image is configured
+func (d Docker) ConfiguredImage() string {
+	// Target image is not configured in dockerfiles
+	return ""
+}
+
+// Path returns the path to the dockerfile
+func (d Docker) Path() string {
+	return string(d)
+}
+
+// ValidateDockerfile makes sure the given Dockerfile is existing and valid.
+func ValidateDockerfile(path string) bool {
+	f, err := os.Open(path)
+	if err != nil {
+		logrus.Warnf("opening file %s: %s", path, err.Error())
+		return false
+	}
+
+	res, err := parser.Parse(f)
+	if err != nil || res == nil || len(res.AST.Children) == 0 {
+		return false
+	}
+
+	// validate each node contains valid dockerfile directive
+	for _, child := range res.AST.Children {
+		_, ok := command.Commands[child.Value]
+		if !ok {
+			return false
+		}
+	}
+
+	return true
+}

pkg/skaffold/docker/docker_init_test.go

@@ -0,0 +1,135 @@
+/*
+Copyright 2019 The Skaffold 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.
+*/
+
+package docker
+
+import (
+	"path/filepath"
+	"testing"
+
+	"github.com/GoogleContainerTools/skaffold/pkg/skaffold/schema/latest"
+	"github.com/GoogleContainerTools/skaffold/testutil"
+)
+
+func TestValidateDockerfile(t *testing.T) {
+	var tests = []struct {
+		description    string
+		content        string
+		fileToValidate string
+		expectedValid  bool
+	}{
+		{
+			description:    "valid",
+			content:        "FROM scratch",
+			fileToValidate: "Dockerfile",
+			expectedValid:  true,
+		},
+		{
+			description:    "invalid command",
+			content:        "GARBAGE",
+			fileToValidate: "Dockerfile",
+			expectedValid:  false,
+		},
+		{
+			description:    "not found",
+			fileToValidate: "Unknown",
+			expectedValid:  false,
+		},
+		{
+			description:    "invalid file",
+			content:        "#escape",
+			fileToValidate: "Dockerfile",
+			expectedValid:  false,
+		},
+	}
+	for _, test := range tests {
+		testutil.Run(t, test.description, func(t *testutil.T) {
+			tmpDir := t.NewTempDir().
+				Write("Dockerfile", test.content)
+
+			valid := ValidateDockerfile(tmpDir.Path(test.fileToValidate))
+
+			t.CheckDeepEqual(test.expectedValid, valid)
+		})
+	}
+}
+
+func TestDescribe(t *testing.T) {
+	var tests = []struct {
+		description    string
+		dockerfile     Docker
+		expectedPrompt string
+	}{
+		{
+			description:    "Dockerfile prompt",
+			dockerfile:     Docker("path/to/Dockerfile"),
+			expectedPrompt: "Docker (path/to/Dockerfile)",
+		},
+	}
+	for _, test := range tests {
+		testutil.Run(t, test.description, func(t *testutil.T) {
+			t.CheckDeepEqual(test.expectedPrompt, test.dockerfile.Describe())
+		})
+	}
+}
+
+func TestCreateArtifact(t *testing.T) {
+	var tests = []struct {
+		description      string
+		dockerfile       Docker
+		manifestImage    string
+		expectedArtifact latest.Artifact
+		expectedImage    string
+	}{
+		{
+			description:   "default filename",
+			dockerfile:    Docker(filepath.Join("path", "to", "Dockerfile")),
+			manifestImage: "image",
+			expectedArtifact: latest.Artifact{
+				ImageName:    "image",
+				Workspace:    filepath.Join("path", "to"),
+				ArtifactType: latest.ArtifactType{},
+			},
+		},
+		{
+			description:   "non-default filename",
+			dockerfile:    Docker(filepath.Join("path", "to", "Dockerfile1")),
+			manifestImage: "image",
+			expectedArtifact: latest.Artifact{
+				ImageName: "image",
+				Workspace: filepath.Join("path", "to"),
+				ArtifactType: latest.ArtifactType{
+					DockerArtifact: &latest.DockerArtifact{DockerfilePath: filepath.Join("path", "to", "Dockerfile1")},
+				},
+			},
+		},
+		{
+			description:   "ignore workspace",
+			dockerfile:    Docker("Dockerfile"),
+			manifestImage: "image",
+			expectedArtifact: latest.Artifact{
+				ImageName:    "image",
+				ArtifactType: latest.ArtifactType{},
+			},
+		},
+	}
+	for _, test := range tests {
+		testutil.Run(t, test.description, func(t *testutil.T) {
+			artifact := test.dockerfile.CreateArtifact(test.manifestImage)
+			t.CheckDeepEqual(test.expectedArtifact, *artifact)
+		})
+	}
+}