generate binary-less dockerfiles

Signed-off-by: Jordan Keister <jordan@nimblewidget.com>

alpha/action/generate_dockerfile.go

@@ -13,14 +13,22 @@ type GenerateDockerfile struct {
 	IndexDir    string
 	ExtraLabels map[string]string
 	Writer      io.Writer
+	Lite        bool
 }
 
 func (i GenerateDockerfile) Run() error {
 	if err := i.validate(); err != nil {
 		return err
 	}
 
-	t, err := template.New("dockerfile").Parse(dockerfileTmpl)
+	var dockerfileTemplate string
+	if i.Lite {
+		dockerfileTemplate = binlessDockerfileTmpl
+	} else {
+		dockerfileTemplate = dockerfileTmpl
+	}
+
+	t, err := template.New("dockerfile").Parse(dockerfileTemplate)
 	if err != nil {
 		// The template is hardcoded in the binary, so if
 		// there is a parse error, it was a programmer error.
@@ -39,6 +47,31 @@ func (i GenerateDockerfile) validate() error {
 	return nil
 }
 
+const binlessDockerfileTmpl = `# The builder image is expected to contain
+# /bin/opm (with serve subcommand)
+FROM {{.BaseImage}} as builder
+
+# Copy FBC root into image at /configs and pre-populate serve cache
+ADD {{.IndexDir}} /configs
+RUN ["/bin/opm", "serve", "/configs", "--cache-dir=/tmp/cache", "--cache-only"]
+
+FROM scratch
+
+COPY --from=builder /configs /configs
+COPY --from=builder /tmp/cache /tmp/cache
+
+# Set FBC-specific label for the location of the FBC root directory
+# in the image
+LABEL ` + containertools.ConfigsLocationLabel + `=/configs
+{{- if .ExtraLabels }}
+
+# Set other custom labels
+{{- range $key, $value := .ExtraLabels }}
+LABEL "{{ $key }}"="{{ $value }}"
+{{- end }}
+{{- end }}
+`
+
 const dockerfileTmpl = `# The base image is expected to contain
 # /bin/opm (with a serve subcommand) and /bin/grpc_health_probe
 FROM {{.BaseImage}}

alpha/action/generate_dockerfile_test.go

@@ -87,6 +87,89 @@ RUN ["/bin/opm", "serve", "/configs", "--cache-dir=/tmp/cache", "--cache-only"]
 # in the image
 LABEL operators.operatorframework.io.index.configs.v1=/configs
 
+# Set other custom labels
+LABEL "key1"="value1"
+LABEL "key2"="value2"
+`,
+		},
+
+		{
+			name: "Lite/Fail/EmptyBaseImage",
+			gen: GenerateDockerfile{
+				IndexDir: "bar",
+				ExtraLabels: map[string]string{
+					"key1": "value1",
+					"key2": "value2",
+				},
+				Lite: true,
+			},
+			expectedErr: "base image is unset",
+		},
+		{
+			name: "Lite/Fail/EmptyFromDir",
+			gen: GenerateDockerfile{
+				BaseImage: "foo",
+				ExtraLabels: map[string]string{
+					"key1": "value1",
+					"key2": "value2",
+				},
+				Lite: true,
+			},
+			expectedErr: "index directory is unset",
+		},
+		{
+			name: "Lite/Success/WithoutExtraLabels",
+			gen: GenerateDockerfile{
+				BaseImage: "foo",
+				IndexDir:  "bar",
+				Lite:      true,
+			},
+			expectedDockerfile: `# The builder image is expected to contain
+# /bin/opm (with serve subcommand)
+FROM foo as builder
+
+# Copy FBC root into image at /configs and pre-populate serve cache
+ADD bar /configs
+RUN ["/bin/opm", "serve", "/configs", "--cache-dir=/tmp/cache", "--cache-only"]
+
+FROM scratch
+
+COPY --from=builder /configs /configs
+COPY --from=builder /tmp/cache /tmp/cache
+
+# Set FBC-specific label for the location of the FBC root directory
+# in the image
+LABEL operators.operatorframework.io.index.configs.v1=/configs
+`,
+		},
+		{
+			name: "Lite/Success/WithExtraLabels",
+			gen: GenerateDockerfile{
+				BaseImage: "foo",
+				IndexDir:  "bar",
+				ExtraLabels: map[string]string{
+					"key1": "value1",
+					"key2": "value2",
+				},
+				Lite: true,
+			},
+			expectedDockerfile: `# The builder image is expected to contain
+# /bin/opm (with serve subcommand)
+FROM foo as builder
+
+# Copy FBC root into image at /configs and pre-populate serve cache
+ADD bar /configs
+RUN ["/bin/opm", "serve", "/configs", "--cache-dir=/tmp/cache", "--cache-only"]
+
+FROM scratch
+
+COPY --from=builder /configs /configs
+COPY --from=builder /tmp/cache /tmp/cache
+
+# Set FBC-specific label for the location of the FBC root directory
+# in the image
+LABEL operators.operatorframework.io.index.configs.v1=/configs
+
 # Set other custom labels
 LABEL "key1"="value1"
 LABEL "key2"="value2"

cmd/opm/generate/cmd.go

@@ -29,6 +29,7 @@ func newDockerfileCmd() *cobra.Command {
 	var (
 		baseImage      string
 		extraLabelStrs []string
+		lite           bool
 	)
 	cmd := &cobra.Command{
 		Use:   "dockerfile <dcRootDir>",
@@ -75,6 +76,7 @@ value of each duplicate key will be added to the generated Dockerfile.
 				IndexDir:    indexName,
 				ExtraLabels: extraLabels,
 				Writer:      f,
+				Lite:        lite,
 			}
 			if err := gen.Run(); err != nil {
 				log.Fatal(err)
@@ -83,6 +85,7 @@ value of each duplicate key will be added to the generated Dockerfile.
 		},
 	}
 	cmd.Flags().StringVarP(&baseImage, "binary-image", "i", containertools.DefaultBinarySourceImage, "Image in which to build catalog.")
+	cmd.Flags().BoolVarP(&lite, "lite", "t", false, "Generate a smaller, binary-less Dockerfile.")
 	cmd.Flags().StringSliceVarP(&extraLabelStrs, "extra-labels", "l", []string{}, "Extra labels to include in the generated Dockerfile. Labels should be of the form 'key=value'.")
 	return cmd
 }