Support additional .dockerignore formats (#579)

* Add function to map additional dockerignore files.

Docker maps "Dockerfile" to a ".dockerignore" file,
and it maps "Dockerfile-prod" to "Dockerfile-prod.dockerignore".

This commit adds a function and unit tests to map the Docker project's
dockerignore file to its expected location.

* Add integration tests for .dockerignore

While these tests cannot precisely verify whether or not a file was correctly
ignored, the docker image being build can expect the
existence/nonexistence of a file in the context tarball and fail
accordingly.

* pacify linter

* remove experimental test

examples/dockerfile_test.go

@@ -75,3 +75,71 @@ func TestDockerfileInContextYAML(t *testing.T) {
 		SkipRefresh: true,
 	})
 }
+
+func TestDockerignoreDefaultYAML(t *testing.T) {
+	cwd, err := os.Getwd()
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+
+	integration.ProgramTest(t, &integration.ProgramTestOptions{
+		Dir:         path.Join(cwd, "test-dockerfile", "dockerignore-default"),
+		Quick:       true,
+		SkipRefresh: true,
+	})
+}
+
+func TestDockerignoreSpecifiedYAML(t *testing.T) {
+	cwd, err := os.Getwd()
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+
+	integration.ProgramTest(t, &integration.ProgramTestOptions{
+		Dir:         path.Join(cwd, "test-dockerfile", "dockerignore-specified"),
+		Quick:       true,
+		SkipRefresh: true,
+	})
+}
+
+func TestDockerignoreDefaultFailYAML(t *testing.T) {
+	cwd, err := os.Getwd()
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+
+	integration.ProgramTest(t, &integration.ProgramTestOptions{
+		Dir:           path.Join(cwd, "test-dockerfile", "dockerignore-default-fail"),
+		Quick:         true,
+		SkipRefresh:   true,
+		ExpectFailure: true,
+	})
+}
+
+func TestDockerignoreNoMappingYAML(t *testing.T) {
+	cwd, err := os.Getwd()
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+	// we expect this test to succeed, as we test that the ignore.txt file does in fact _not_ get ignored
+	// the ignore.txt file does not get ignored, as  .dockerignore does not map to Mockerfile.
+	// The RUN command in Mockerfile therefore succeeds.
+	integration.ProgramTest(t, &integration.ProgramTestOptions{
+		Dir:         path.Join(cwd, "test-dockerfile", "dockerignore-no-mapping"),
+		Quick:       true,
+		SkipRefresh: true,
+	})
+}
+
+func TestDockerignoreWithExternalDockerfileYAML(t *testing.T) {
+	cwd, err := os.Getwd()
+	if !assert.NoError(t, err) {
+		t.FailNow()
+	}
+
+	integration.ProgramTest(t, &integration.ProgramTestOptions{
+		Dir:         path.Join(cwd, "test-dockerfile", "dockerignore-with-external-dockerfile"),
+		Quick:       true,
+		SkipRefresh: true,
+	})
+}

examples/test-dockerfile/dockerignore-default-fail/.dockerignore

@@ -0,0 +1 @@
+ignore.txt

examples/test-dockerfile/dockerignore-default-fail/Dockerfile

@@ -0,0 +1,8 @@
+FROM --platform=linux/amd64 ubuntu
+
+COPY . /
+
+RUN cat app.txt
+
+Run cat ignore.txt
+

examples/test-dockerfile/dockerignore-default-fail/Pulumi.yaml

@@ -0,0 +1,13 @@
+name: dockerfile-default
+runtime: yaml
+resources:
+  demo-image:
+    type: docker:Image
+    properties:
+      imageName: pulumibot/ignore-image:tag2
+      skipPush: true
+    options:
+      version: v4.0.0
+outputs:
+  imageName: ${demo-image.imageName}
+  out-dockerfile: ${demo-image.dockerfile}

examples/test-dockerfile/dockerignore-default-fail/app.txt

@@ -0,0 +1 @@
+Hi! I am a test file!

examples/test-dockerfile/dockerignore-default-fail/ignore.txt

@@ -0,0 +1 @@
+Hi! I should get ignored!

examples/test-dockerfile/dockerignore-default/.dockerignore

@@ -0,0 +1 @@
+ignore.txt

examples/test-dockerfile/dockerignore-default/Dockerfile

@@ -0,0 +1,3 @@
+FROM scratch
+
+COPY . /

examples/test-dockerfile/dockerignore-default/Pulumi.yaml

@@ -0,0 +1,13 @@
+name: dockerfile-default
+runtime: yaml
+resources:
+  demo-image:
+    type: docker:Image
+    properties:
+      imageName: pulumibot/ignore-image:tag1
+      skipPush: true
+    options:
+      version: v4.0.0
+outputs:
+  imageName: ${demo-image.imageName}
+  out-dockerfile: ${demo-image.dockerfile}

examples/test-dockerfile/dockerignore-default/app.txt

@@ -0,0 +1 @@
+Hi! I am a test file!

examples/test-dockerfile/dockerignore-default/ignore.txt

@@ -0,0 +1 @@
+Hi! I should get ignored!

examples/test-dockerfile/dockerignore-no-mapping/.dockerignore

@@ -0,0 +1 @@
+ignore.txt

examples/test-dockerfile/dockerignore-no-mapping/Mockerfile

@@ -0,0 +1,7 @@
+FROM --platform=linux/amd64 ubuntu
+
+COPY . /
+
+Run cat app.txt
+
+RUN cat ignore.txt

examples/test-dockerfile/dockerignore-no-mapping/Pulumi.yaml

@@ -0,0 +1,16 @@
+name: dockerfile-default
+runtime: yaml
+resources:
+  demo-image:
+    type: docker:Image
+    properties:
+      imageName: pulumibot/ignore-image:tag4
+      skipPush: true
+      build:
+        context: .
+        dockerfile: Mockerfile
+    options:
+      version: v4.0.0
+outputs:
+  imageName: ${demo-image.imageName}
+  out-dockerfile: ${demo-image.dockerfile}

examples/test-dockerfile/dockerignore-no-mapping/app.txt

@@ -0,0 +1 @@
+Hi! I am a test file!

examples/test-dockerfile/dockerignore-no-mapping/ignore.txt

@@ -0,0 +1 @@
+Hi! I should get ignored!

examples/test-dockerfile/dockerignore-specified/Mockerfile

@@ -0,0 +1,3 @@
+FROM --platform=linux/amd64 ubuntu
+
+COPY . /

examples/test-dockerfile/dockerignore-specified/Mockerfile.dockerignore

@@ -0,0 +1 @@
+ignore.txt

examples/test-dockerfile/dockerignore-specified/Pulumi.yaml

@@ -0,0 +1,16 @@
+name: dockerfile-default
+runtime: yaml
+resources:
+  demo-image:
+    type: docker:Image
+    properties:
+      imageName: pulumibot/ignore-image:tag3
+      skipPush: true
+      build:
+        context: .
+        dockerfile: Mockerfile
+    options:
+      version: v4.0.0
+outputs:
+  imageName: ${demo-image.imageName}
+  out-dockerfile: ${demo-image.dockerfile}

examples/test-dockerfile/dockerignore-specified/app.txt

@@ -0,0 +1 @@
+Hi! I am a test file!

examples/test-dockerfile/dockerignore-specified/ignore.txt

@@ -0,0 +1 @@
+Hi! I should get ignored!

examples/test-dockerfile/dockerignore-with-external-dockerfile/Dockerfile

@@ -0,0 +1,5 @@
+FROM --platform=linux/amd64 ubuntu
+
+COPY . /
+
+RUN cat app.txt

examples/test-dockerfile/dockerignore-with-external-dockerfile/Pulumi.yaml

@@ -0,0 +1,16 @@
+name: dockerfile-external
+runtime: yaml
+resources:
+  demo-image:
+    type: docker:Image
+    properties:
+      imageName: pulumibot/test-image:tag3
+      skipPush: true
+      build:
+        context: ./app
+        dockerfile: ./Dockerfile
+    options:
+      version: v4.0.0
+outputs:
+  imageName: ${demo-image.imageName}
+  out-dockerfile: ${demo-image.dockerfile}

examples/test-dockerfile/dockerignore-with-external-dockerfile/app/.dockerignore

@@ -0,0 +1 @@
+ignore.txt

examples/test-dockerfile/dockerignore-with-external-dockerfile/app/app.txt

@@ -0,0 +1 @@
+Hi! I am a test file!

provider/image.go

@@ -118,7 +118,10 @@ func (p *dockerNativeProvider) dockerBuild(ctx context.Context,
 	}
 
 	// make the build context and ensure to exclude dockerignore file patterns
-	dockerIgnorePath := filepath.Join(build.Context, ".dockerignore")
+	// map the expected location for dockerignore
+	dockerignore := mapDockerignore(filepath.Base(build.Dockerfile))
+	dockerIgnorePath := filepath.Join(build.Context, dockerignore)
+
 	initialIgnorePatterns, err := getIgnore(dockerIgnorePath)
 	if err != nil {
 		return "", nil, fmt.Errorf("error reading ignore file: %w", err)
@@ -806,3 +809,19 @@ func defaultPooledTransport() *http.Transport {
 	}
 	return transport
 }
+
+func mapDockerignore(dockerfile string) string {
+	// Docker maps `Dockerfile` -> `.dockerignore`
+	// Nonstandard dockerfile names map to a file with a `.dockerignore` extension
+	// e.g. `Mockerfile` -> `Mockerfile.dockerignore`
+	// Note that we do not verify the existence of a .dockerignore file; we only map the name that it would have.
+
+	ignore := ".dockerignore"
+
+	// Add extension for nonstandardly named Dockerfiles
+	if dockerfile != defaultDockerfile {
+		ignore = dockerfile + ignore
+	}
+	// Return the default dockerignore name.
+	return ignore
+}

provider/image_test.go

@@ -497,3 +497,20 @@ func TestConfigureDockerClient(t *testing.T) {
 	})
 
 }
+
+func TestMapDockerignore(t *testing.T) {
+
+	t.Run("Returns default .dockerignore", func(t *testing.T) {
+		expected := ".dockerignore"
+		input := defaultDockerfile
+		actual := mapDockerignore(input)
+		assert.Equal(t, expected, actual)
+	})
+	t.Run("Returns .dockerignore extension for nonstandard dockerfile names", func(t *testing.T) {
+		expected := "special.dockerfile.dockerignore"
+		input := "special.dockerfile"
+		actual := mapDockerignore(input)
+		assert.Equal(t, expected, actual)
+	})
+
+}

provider/provider.go

@@ -523,7 +523,7 @@ func (accumulator *contextHashAccumulator) hexSumContext() string {
 
 func hashContext(dockerContextPath string, dockerfile string) (string, error) {
 	// exclude all files listed in dockerignore
-	dockerIgnorePath := filepath.Join(dockerContextPath, ".dockerignore")
+	dockerIgnorePath := filepath.Join(dockerContextPath, mapDockerignore(filepath.Base(dockerfile)))
 	ignorePatterns, err := getIgnore(dockerIgnorePath)
 	if err != nil {
 		return "", err