Add check-conformance-test-requirements.go

We have defined requirements of conformance test as [1], and this
adds coding check for one requirement "it works for all providers".

[1]: https://github.com/kubernetes/community/blob/master/contributors/devel/sig-architecture/conformance-tests.md#conformance-test-requirements

hack/BUILD

@@ -19,6 +19,7 @@ filegroup(
     srcs = [
         ":package-srcs",
         "//hack/boilerplate:all-srcs",
+        "//hack/conformance:all-srcs",
         "//hack/e2e-internal:all-srcs",
         "//hack/lib:all-srcs",
         "//hack/make-rules:all-srcs",

hack/conformance/BUILD

@@ -0,0 +1,32 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_binary", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["check_conformance_test_requirements.go"],
+    importpath = "k8s.io/kubernetes/hack/conformance",
+    visibility = ["//visibility:private"],
+    deps = [
+        "//vendor/github.com/pkg/errors:go_default_library",
+        "//vendor/github.com/spf13/cobra:go_default_library",
+    ],
+)
+
+go_binary(
+    name = "conformance",
+    embed = [":go_default_library"],
+    visibility = ["//visibility:public"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

hack/conformance/check_conformance_test_requirements.go

@@ -0,0 +1,157 @@
+/*
+Copyright 2019 The Kubernetes 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.
+*/
+
+// This tool is for checking conformance e2e tests follow the requirements
+// which is https://github.com/kubernetes/community/blob/master/contributors/devel/sig-architecture/conformance-tests.md#conformance-test-requirements
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"regexp"
+
+	"github.com/pkg/errors"
+	"github.com/spf13/cobra"
+)
+
+const (
+	//e.g. framework.ConformanceIt("should provide secure master service ", func() {
+	patternStartConformance = "framework.ConformanceIt\\(.*, func\\(\\) {$"
+	patternEndConformance   = "}\\)$"
+	patternSkipProviderIs   = "Skip.*ProviderIs\\("
+)
+
+// This function checks the requirement: it works for all providers (e.g., no SkipIfProviderIs/SkipUnlessProviderIs calls)
+func checkAllProviders(e2eFile string) error {
+	checkFailed := false
+	inConformanceCode := false
+
+	regStartConformance := regexp.MustCompile(patternStartConformance)
+	regEndConformance := regexp.MustCompile(patternEndConformance)
+	regSkipProviderIs := regexp.MustCompile(patternSkipProviderIs)
+
+	fileInput, err := ioutil.ReadFile(e2eFile)
+	if err != nil {
+		return errors.Wrapf(err, "Failed to read file %s", e2eFile)
+	}
+	scanner := bufio.NewScanner(bytes.NewReader(fileInput))
+	scanner.Split(bufio.ScanLines)
+
+	for scanner.Scan() {
+		line := scanner.Text()
+		if regStartConformance.MatchString(line) {
+			if inConformanceCode {
+				return errors.Errorf("Missed the end of previous conformance test. There might be a bug in this script.")
+			}
+			inConformanceCode = true
+		}
+		if inConformanceCode {
+			if regSkipProviderIs.MatchString(line) {
+				// To list all invalid places in a single operation of this tool, here doesn't return error and continues checking.
+				fmt.Fprintf(os.Stderr, "%v: Conformance test should not call SkipIfProviderIs()/SkipUnlessProviderIs()\n", e2eFile)
+				checkFailed = true
+			}
+			if regEndConformance.MatchString(line) {
+				inConformanceCode = false
+			}
+		}
+	}
+	if inConformanceCode {
+		return errors.Errorf("Missed the end of previous conformance test. There might be a bug in this script.")
+	}
+	if checkFailed {
+		return errors.Errorf("We need to fix the above errors.")
+	}
+	return nil
+}
+
+func processFile(e2ePath string) error {
+	regGoFile := regexp.MustCompile(".*.go")
+
+	files, err := ioutil.ReadDir(e2ePath)
+	if err != nil {
+		return errors.Wrapf(err, "Failed to read dir %s", e2ePath)
+	}
+	for _, file := range files {
+		if file.IsDir() {
+			continue
+		}
+		if !regGoFile.MatchString(file.Name()) {
+			continue
+		}
+		e2eFile := fmt.Sprintf("%s/%s", e2ePath, file.Name())
+		err = checkAllProviders(e2eFile)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func processDir(e2ePath string) error {
+	err := processFile(e2ePath)
+	if err != nil {
+		return err
+	}
+
+	// Search sub directories if exist
+	files, err := ioutil.ReadDir(e2ePath)
+	if err != nil {
+		return errors.Wrapf(err, "Failed to read dir %s", e2ePath)
+	}
+	for _, file := range files {
+		if !file.IsDir() {
+			continue
+		}
+		err = processDir(fmt.Sprintf("%s/%s", e2ePath, file.Name()))
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func newCommand() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "check_conformance_test_requirements [e2e-test-path]",
+		Short: "Check conformance test code follows the requirements",
+		Run: func(cmd *cobra.Command, args []string) {
+			if len(args) != 1 {
+				cmd.Help()
+				os.Exit(1)
+			}
+			e2eRootPath := args[0]
+			err := processDir(e2eRootPath)
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "Error: %v\n", err)
+				os.Exit(1)
+			}
+			os.Exit(0)
+		},
+	}
+	return cmd
+}
+
+func main() {
+	command := newCommand()
+	if err := command.Execute(); err != nil {
+		fmt.Fprintf(os.Stderr, "error: %v\n", err)
+		os.Exit(1)
+	}
+}