From de3032f982bbe125c412397c9da7aac2dec87ccc Mon Sep 17 00:00:00 2001
From: Angus Williams <anguswilliams@gmail.com>
Date: Thu, 15 Jun 2023 05:20:28 +1200
Subject: [PATCH] Refactors IsSrcRemoteFileURL to only validate the URL is
 valid (#2563)

`IsSrcRemoteFileURL` was doing a `http.Get` call to make sure the URL was valid, but not surfacing any errors.
Because the error from the http.Get call is not handled, some useful information can be buried.
It also means kaniko will download the file twice during a build, once to validate, and once to actually add the file
to the image.
Removing the http.Get call and validating the URL is valid, and has the correct schema and hostname will stop
the double handling, and allow any errors to be surfaced through the error handing in the file download function.

Fixes #1590

Signed-off-by: Angus Williams <anguswilliams@gmail.com>
---
 pkg/util/command_util.go      |  9 +----
 pkg/util/command_util_test.go | 73 ++++++++++++++++++++---------------
 2 files changed, 43 insertions(+), 39 deletions(-)

diff --git a/pkg/util/command_util.go b/pkg/util/command_util.go
index 02aa847be..448a59236 100644
--- a/pkg/util/command_util.go
+++ b/pkg/util/command_util.go
@@ -18,7 +18,6 @@ package util
 
 import (
 	"fmt"
-	"net/http"
 	"net/url"
 	"os"
 	"os/user"
@@ -291,12 +290,8 @@ func IsSrcsValid(srcsAndDest instructions.SourcesAndDest, resolvedSources []stri
 }
 
 func IsSrcRemoteFileURL(rawurl string) bool {
-	_, err := url.ParseRequestURI(rawurl)
-	if err != nil {
-		return false
-	}
-	_, err = http.Get(rawurl) //nolint:noctx
-	return err == nil
+	u, err := url.ParseRequestURI(rawurl)
+	return err == nil && u.Scheme != "" && u.Host != ""
 }
 
 func UpdateConfigEnv(envVars []instructions.KeyValuePair, config *v1.Config, replacementEnvs []string) error {
diff --git a/pkg/util/command_util_test.go b/pkg/util/command_util_test.go
index 47fed6f74..3d8384771 100644
--- a/pkg/util/command_util_test.go
+++ b/pkg/util/command_util_test.go
@@ -521,38 +521,6 @@ func Test_ResolveSources(t *testing.T) {
 	}
 }
 
-var testRemoteUrls = []struct {
-	name  string
-	url   string
-	valid bool
-}{
-	{
-		name:  "Valid URL",
-		url:   "https://google.com",
-		valid: true,
-	},
-	{
-		name:  "Invalid URL",
-		url:   "not/real/",
-		valid: false,
-	},
-	{
-		name:  "URL which fails on GET",
-		url:   "https://thereisnowaythiswilleverbearealurlrightrightrightcatsarethebest.com/something/not/real",
-		valid: false,
-	},
-}
-
-func Test_RemoteUrls(t *testing.T) {
-	for _, test := range testRemoteUrls {
-		t.Run(test.name, func(t *testing.T) {
-			valid := IsSrcRemoteFileURL(test.url)
-			testutil.CheckErrorAndDeepEqual(t, false, nil, test.valid, valid)
-		})
-	}
-
-}
-
 func TestGetUserGroup(t *testing.T) {
 	tests := []struct {
 		description  string
@@ -855,3 +823,44 @@ func TestLookupUser(t *testing.T) {
 	}
 
 }
+
+func TestIsSrcRemoteFileURL(t *testing.T) {
+	type args struct {
+		rawurl string
+	}
+	tests := []struct {
+		name string
+		args args
+		want bool
+	}{
+		{
+			name: "valid https url",
+			args: args{rawurl: "https://google.com?foo=bar"},
+			want: true,
+		},
+		{
+			name: "valid http url",
+			args: args{rawurl: "http://example.com/foobar.tar.gz"},
+			want: true,
+		},
+		{
+			name: "invalid url",
+			args: args{rawurl: "http:/not-a-url.com"},
+			want: false,
+		},
+		{
+			name: "invalid url filepath",
+			args: args{rawurl: "/is/a/filepath"},
+			want: false,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(
+			tt.name, func(t *testing.T) {
+				if got := IsSrcRemoteFileURL(tt.args.rawurl); got != tt.want {
+					t.Errorf("IsSrcRemoteFileURL() = %v, want %v", got, tt.want)
+				}
+			},
+		)
+	}
+}