Add command with unit tests

pkg/util/command_util.go

@@ -22,6 +22,8 @@ import (
 	"github.com/docker/docker/builder/dockerfile/shell"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+	"net/http"
+	"net/url"
 	"os"
 	"path/filepath"
 	"strings"
@@ -31,6 +33,10 @@ import (
 func ResolveEnvironmentReplacementList(values, envs []string, isFilepath bool) ([]string, error) {
 	var resolvedValues []string
 	for _, value := range values {
+		if IsSrcRemoteFileURL(value) {
+			resolvedValues = append(resolvedValues, value)
+			continue
+		}
 		resolved, err := ResolveEnvironmentReplacement(value, envs, isFilepath)
 		logrus.Debugf("Resolved %s to %s", value, resolved)
 		if err != nil {
@@ -106,13 +112,17 @@ func ResolveSources(srcsAndDest instructions.SourcesAndDest, root string) (map[s
 func matchSources(srcs, files []string) ([]string, error) {
 	var matchedSources []string
 	for _, src := range srcs {
+		if IsSrcRemoteFileURL(src) {
+			matchedSources = append(matchedSources, src)
+			continue
+		}
 		src = filepath.Clean(src)
 		for _, file := range files {
 			matched, err := filepath.Match(src, file)
 			if err != nil {
 				return nil, err
 			}
-			if matched {
+			if matched || src == file {
 				matchedSources = append(matchedSources, file)
 			}
 		}
@@ -160,10 +170,31 @@ func DestinationFilepath(filename, srcName, dest, cwd, buildcontext string) (str
 	return filepath.Join(cwd, dest), nil
 }
 
+// URLDestinationFilepath gives the destintion a file from a remote URL should be saved to
+func URLDestinationFilepath(rawurl, dest, cwd string) string {
+	if !IsDestDir(dest) {
+		if !filepath.IsAbs(dest) {
+			return filepath.Join(cwd, dest)
+		}
+		return dest
+	}
+	urlBase := filepath.Base(rawurl)
+	destPath := filepath.Join(dest, urlBase)
+
+	if !filepath.IsAbs(dest) {
+		destPath = filepath.Join(cwd, destPath)
+	}
+	return destPath
+}
+
 // SourcesToFilesMap returns a map of [src]:[files rooted at source]
 func SourcesToFilesMap(srcs []string, root string) (map[string][]string, error) {
 	srcMap := make(map[string][]string)
 	for _, src := range srcs {
+		if IsSrcRemoteFileURL(src) {
+			srcMap[src] = []string{src}
+			continue
+		}
 		src = filepath.Clean(src)
 		files, err := RelativeFiles(src, root)
 		if err != nil {
@@ -202,3 +233,15 @@ func IsSrcsValid(srcsAndDest instructions.SourcesAndDest, srcMap map[string][]st
 	}
 	return nil
 }
+
+func IsSrcRemoteFileURL(rawurl string) bool {
+	_, err := url.ParseRequestURI(rawurl)
+	if err != nil {
+		return false
+	}
+	_, err = http.Get(rawurl)
+	if err != nil {
+		return false
+	}
+	return true
+}