improve S3 url parsing for vfsPath to support more naming conventions

pkg/acls/s3/storage.go

@@ -56,9 +56,9 @@ func (s *s3PublicAclStrategy) GetACL(p vfs.Path, cluster *kops.Cluster) (vfs.ACL
 		return "", fmt.Errorf("unable to parse: %q", fileRepository)
 	}
 
-	// We are checking that the file is in s3.amazonaws.com meaning that it is in s3
-	// This will miss edge cases when the region url is used.
-	if u.Host != "s3.amazonaws.com" {
+	// We are checking that the file repository url is in S3
+	_, err = vfs.VFSPath(fileRepository)
+	if err != nil {
 		glog.V(8).Infof("path %q is not inside of a s3 bucket", u.String)
 		return nil, nil
 	}

upup/pkg/fi/assettasks/copyfile.go

@@ -197,26 +197,36 @@ func buildVFSPath(target string) (string, error) {
 		return target, nil
 	}
 
-	u, err := url.Parse(target)
-	if err != nil {
-		return "", fmt.Errorf("unable to parse url: %q", target)
-	}
-
 	var vfsPath string
 
-	// These matches only cover a subset of the URLs that you can use, but I am uncertain how to cover more of the possible
-	// options.
-	// This code parses the HOST and determines to use s3 or gs.
-	// URLs.  For instance you can have the bucket name in the s3 url hostname.
-	// We are translating known https urls such as https://s3.amazonaws.com/example-kops to vfs path like
-	// s3://example-kops
-	if u.Host == "s3.amazonaws.com" {
-		vfsPath = "s3:/" + u.Path
-	} else if u.Host == "storage.googleapis.com" {
-		vfsPath = "gs:/" + u.Path
+	// Matches all S3 regional naming conventions:
+	// https://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region
+	// and converts to a s3://<bucket>/<path> vfsPath
+	s3VfsPath, err := vfs.VFSPath(target)
+	if err == nil {
+		vfsPath = s3VfsPath
 	} else {
-		glog.Errorf("unable to determine vfs path s3, google storage, and file paths are supported")
-		glog.Errorf("URLs starting with https://s3.amazonaws.com and http://storage.googleapis.com are transformed into s3 and gs URLs")
+		// These matches only cover a subset of the URLs that you can use, but I am uncertain how to cover more of the possible
+		// options.
+		// This code parses the HOST and determines gs URLs.
+		// For instance you can have the bucket name in the gs url hostname.
+		u, err := url.Parse(target)
+		if err != nil {
+			return "", fmt.Errorf("Unable to parse Google Cloud Storage URL: %q", target)
+		}
+		if u.Host == "storage.googleapis.com" {
+			vfsPath = "gs:/" + u.Path
+		}
+	}
+
+	if vfsPath == "" {
+		glog.Errorf("Unable to determine VFS path from supplied URL: %s", target)
+		glog.Errorf("S3, Google Cloud Storage, and File Paths are supported.")
+		glog.Errorf("For S3, please make sure that the supplied file repository URL adhere to S3 naming conventions, https://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region.")
+		glog.Errorf("For GCS, please make sure that the supplied file repository URL adheres to https://storage.googleapis.com/")
+		if err != nil { // print the S3 error for more details
+			return "", fmt.Errorf("Error Details: %v", err)
+		}
 		return "", fmt.Errorf("unable to determine vfs type for %q", target)
 	}
 

upup/pkg/fi/assettasks/copyfile_test.go

@@ -32,6 +32,26 @@ func Test_BuildVFSPath(t *testing.T) {
 			"s3://k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
 			true,
 		},
+		{
+			"https://s3.cn-north-1.amazonaws.com/k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			"s3://k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			true,
+		},
+		{
+			"https://s3-cn-north-1.amazonaws.com/k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			"s3://k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			true,
+		},
+		{
+			"https://s3.k8s-for-greeks-kops.amazonaws.com/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			"s3://k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			true,
+		},
+		{
+			"https://s3-k8s-for-greeks-kops.amazonaws.com/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			"s3://k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
+			true,
+		},
 		{
 			"https://foo/k8s-for-greeks-kops/kubernetes-release/release/v1.7.2/bin/linux/amd64/kubectl",
 			"",

util/pkg/vfs/s3context.go

@@ -19,6 +19,7 @@ package vfs
 import (
 	"fmt"
 	"os"
+	"regexp"
 	"sync"
 	"time"
 
@@ -31,6 +32,14 @@ import (
 	"github.com/golang/glog"
 )
 
+var (
+	// matches all regional naming conventions of S3:
+	// https://docs.aws.amazon.com/general/latest/gr/rande.html#s3_region
+	// TODO: perhaps make region regex more specific, ie. (us|eu|ap|cn|ca|sa), to prevent catching bucket names that match region format?
+	//       but that will mean updating this list when AWS introduces new regions
+	s3UrlRegexp = regexp.MustCompile(`s3([-.](?P<region>\w{2}-\w+-\d{1})|[-.](?P<bucket>[\w.\-\_]+)|)?.amazonaws.com(.cn)?(?P<path>.*)?`)
+)
+
 type S3Context struct {
 	mutex           sync.Mutex
 	clients         map[string]*s3.S3
@@ -230,3 +239,25 @@ func validateRegion(region string) error {
 	}
 	return fmt.Errorf("%s is not a valid region\nPlease check that your region is formatted correctly (i.e. us-east-1)", region)
 }
+
+func VFSPath(url string) (string, error) {
+	if !s3UrlRegexp.MatchString(url) {
+		return "", fmt.Errorf("%s is not a valid S3 URL", url)
+	}
+	groupNames := s3UrlRegexp.SubexpNames()
+	result := s3UrlRegexp.FindAllStringSubmatch(url, -1)[0]
+
+	captured := map[string]string{}
+	for i, value := range result {
+		captured[groupNames[i]] = value
+	}
+	bucket := captured["bucket"]
+	path := captured["path"]
+	if bucket == "" {
+		if path == "" {
+			return "", fmt.Errorf("%s is not a valid S3 URL. No bucket defined.", url)
+		}
+		return fmt.Sprintf("s3:/%s", path), nil
+	}
+	return fmt.Sprintf("s3://%s%s", bucket, path), nil
+}

util/pkg/vfs/s3context_test.go

@@ -0,0 +1,128 @@
+/*
+Copyright 2018 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.
+*/
+
+package vfs
+
+import "testing"
+
+func Test_VFSPath(t *testing.T) {
+	grid := []struct {
+		Input          string
+		ExpectedResult string
+		ExpectError    bool
+	}{
+		{
+			Input:          "s3.amazonaws.com/bucket",
+			ExpectedResult: "s3://bucket",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3-bucket.amazonaws.com",
+			ExpectedResult: "s3://bucket",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3-bucket.amazonaws.com/path",
+			ExpectedResult: "s3://bucket/path",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3.bucket.amazonaws.com",
+			ExpectedResult: "s3://bucket",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3.bucket_foo-bar.abc.amazonaws.com/path",
+			ExpectedResult: "s3://bucket_foo-bar.abc/path",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3-us-west-2.amazonaws.com/bucket/path",
+			ExpectedResult: "s3://bucket/path",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3-us-west-2.amazonaws.com/bucket/path",
+			ExpectedResult: "s3://bucket/path",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3.cn-north-1.amazonaws.com.cn/bucket",
+			ExpectedResult: "s3://bucket",
+			ExpectError:    false,
+		},
+		{
+			Input:          "s3.cn-north-1.amazonaws.com.cn/bucket/path",
+			ExpectedResult: "s3://bucket/path",
+			ExpectError:    false,
+		},
+		{
+			Input:          "https://s3.amazonaws.com/bucket",
+			ExpectedResult: "s3://bucket",
+			ExpectError:    false,
+		},
+		{
+			Input:          "http://s3.amazonaws.com/bucket",
+			ExpectedResult: "s3://bucket",
+			ExpectError:    false,
+		},
+		{
+			Input:          "example.com/bucket",
+			ExpectedResult: "",
+			ExpectError:    true,
+		},
+		{
+			Input:          "https://example.com/bucket",
+			ExpectedResult: "",
+			ExpectError:    true,
+		},
+		{
+			Input:          "storage.googleapis.com",
+			ExpectedResult: "",
+			ExpectError:    true,
+		},
+		{
+			Input:          "storage.googleapis.com/foo/bar",
+			ExpectedResult: "",
+			ExpectError:    true,
+		},
+		{
+			Input:          "https://storage.googleapis.com",
+			ExpectedResult: "",
+			ExpectError:    true,
+		},
+		{
+			Input:          "https://storage.googleapis.com/foo/bar",
+			ExpectedResult: "",
+			ExpectError:    true,
+		},
+	}
+	for _, g := range grid {
+		vfsPath, err := VFSPath(g.Input)
+		if !g.ExpectError {
+			if err != nil {
+				t.Fatalf("unexpected error parsing vfs path: %v", err)
+			}
+			if vfsPath != g.ExpectedResult {
+				t.Fatalf("s3 url does not match expected result (%v): %v", g.ExpectedResult, g.Input)
+			}
+		} else {
+			if err == nil {
+				t.Fatalf("unexpected error parsing %q", g.Input)
+			}
+		}
+	}
+}