test: add e2e specs for oras pull (#693)

Resolves: #567
Signed-off-by: Billy Zha <jinzha1@microsoft.com>

test/e2e/suite/command/pull.go

@@ -0,0 +1,111 @@
+/*
+Copyright The ORAS 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 command
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+	"github.com/onsi/gomega/gbytes"
+	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"oras.land/oras-go/v2"
+	. "oras.land/oras/test/e2e/internal/utils"
+	"oras.land/oras/test/e2e/internal/utils/match"
+)
+
+var _ = Describe("Remote registry users:", func() {
+	When("pulling images from remote registry", func() {
+		var (
+			repo  = "command/images"
+			tag   = "foobar"
+			files = []string{
+				"config.json",
+				"foo1",
+				"foo2",
+				"bar",
+			}
+		)
+
+		It("should pull all files in an image to a target folder", func() {
+			pullRoot := "pulled"
+			tempDir := GinkgoT().TempDir()
+			if err := CopyTestData(tempDir); err != nil {
+				panic(err)
+			}
+			ORAS("pull", Reference(Host, repo, tag), "-v", "--config", files[0], "-o", pullRoot).
+				MatchStatus([]match.StateKey{
+					{Digest: "fd6ed2f36b54", Name: ocispec.MediaTypeImageManifest},
+					{Digest: "44136fa355b3", Name: files[0]},
+					{Digest: "2c26b46b68ff", Name: files[1]},
+					{Digest: "2c26b46b68ff", Name: files[2]},
+					{Digest: "fcde2b2edba5", Name: files[3]},
+				}, true, 5).
+				WithWorkDir(tempDir).Exec()
+			// check config
+			configPath := filepath.Join(tempDir, pullRoot, files[0])
+			Expect(configPath).Should(BeAnExistingFile())
+			f, err := os.Open(configPath)
+			Expect(err).ShouldNot(HaveOccurred())
+			defer f.Close()
+			Eventually(gbytes.BufferReader(f)).Should(gbytes.Say("{}"))
+			for _, f := range files[1:] {
+				// check layers
+				Binary("diff", filepath.Join(tempDir, "foobar", f), filepath.Join(pullRoot, f)).
+					WithWorkDir(tempDir).Exec()
+			}
+
+			ORAS("pull", Reference(Host, repo, tag), "-v", "-o", pullRoot, "--keep-old-files").
+				WithFailureCheck().
+				WithDescription("fail if overwrite old files are disabled")
+		})
+
+		It("should skip config if media type not matching", func() {
+			pullRoot := "pulled"
+			tempDir := GinkgoT().TempDir()
+			if err := CopyTestData(tempDir); err != nil {
+				panic(err)
+			}
+			ORAS("pull", Reference(Host, repo, tag), "-v", "--config", fmt.Sprintf("%s:%s", files[0], "???"), "-o", pullRoot).
+				MatchStatus([]match.StateKey{
+					{Digest: "fd6ed2f36b54", Name: ocispec.MediaTypeImageManifest},
+					{Digest: "44136fa355b3", Name: oras.MediaTypeUnknownConfig},
+					{Digest: "2c26b46b68ff", Name: files[1]},
+					{Digest: "2c26b46b68ff", Name: files[2]},
+					{Digest: "fcde2b2edba5", Name: files[3]},
+				}, true, 5).
+				WithWorkDir(tempDir).Exec()
+			// check config
+			Expect(filepath.Join(pullRoot, files[0])).ShouldNot(BeAnExistingFile())
+			for _, f := range files[1:] {
+				// check layers
+				Binary("diff", filepath.Join(tempDir, "foobar", f), filepath.Join(pullRoot, f)).
+					WithWorkDir(tempDir).
+					WithDescription("should download identical file " + f).Exec()
+			}
+		})
+
+		It("should pull specific platform", func() {
+			tempDir := GinkgoT().TempDir()
+			ORAS("pull", Reference(Host, repo, "multi"), "--platform", "linux/amd64", "-v", "-o", tempDir).
+				MatchStatus([]match.StateKey{
+					{Digest: "9d84a5716c66", Name: ocispec.MediaTypeImageManifest},
+					{Digest: "fe9dbc99451d", Name: ocispec.MediaTypeImageConfig},
+					{Digest: "2ef548696ac7", Name: "hello.tar"},
+				}, true, 3).Exec()
+		})
+	})
+})