internal/pkg: implement tar artifact

This is useful for unpacking tarballs downloaded from the internet.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/pkg/tar_test.go

@@ -0,0 +1,119 @@
+package pkg_test
+
+import (
+	"archive/tar"
+	"bytes"
+	"compress/gzip"
+	"crypto/sha512"
+	"io/fs"
+	"net/http"
+	"testing"
+	"testing/fstest"
+
+	"hakurei.app/container/check"
+	"hakurei.app/internal/pkg"
+)
+
+func TestTar(t *testing.T) {
+	t.Parallel()
+
+	testdataFsys := fstest.MapFS{
+		".": {Mode: fs.ModeDir | 0700},
+
+		"checksum": {Mode: fs.ModeDir | 0700},
+		"checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP":                {Mode: fs.ModeDir | 0700},
+		"checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP/check":          {Mode: 0400, Data: []byte{0, 0}},
+		"checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP/lib":            {Mode: fs.ModeDir | 0700},
+		"checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP/lib/pkgconfig":  {Mode: fs.ModeDir | 0700},
+		"checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP/lib/libedac.so": {Mode: 01000000777, Data: []byte("/proc/nonexistent/libedac.so")},
+
+		"identifier": {Mode: fs.ModeDir | 0700},
+		"identifier/HnySzeLQvSBZuTUcvfmLEX_OmH4yJWWH788NxuLuv7kVn8_uPM6Ks4rqFWM2NZJY": {Mode: 01000000777, Data: []byte("../checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP")},
+		"identifier/Zx5ZG9BAwegNT3zQwCySuI2ktCXxNgxirkGLFjW4FW06PtojYVaCdtEw8yuntPLa": {Mode: 01000000777, Data: []byte("../checksum/1TL00Qb8dcqayX7wTO8WNaraHvY6b-KCsctLDTrb64QBCmxj_-byK1HdIUwMaFEP")},
+
+		"work": {Mode: fs.ModeDir | 0700},
+	}
+
+	var testdata string
+	{
+		var buf bytes.Buffer
+		w := tar.NewWriter(&buf)
+		if err := w.AddFS(testdataFsys); err != nil {
+			t.Fatalf("AddFS: error = %v", err)
+		}
+		if err := w.Close(); err != nil {
+			t.Fatalf("Close: error = %v", err)
+		}
+
+		var zbuf bytes.Buffer
+		gw := gzip.NewWriter(&zbuf)
+		if _, err := gw.Write(buf.Bytes()); err != nil {
+			t.Fatalf("Write: error = %v", err)
+		}
+		if err := gw.Close(); err != nil {
+			t.Fatalf("Close: error = %v", err)
+		}
+		testdata = zbuf.String()
+	}
+
+	testdataChecksum := func() pkg.Checksum {
+		h := sha512.New384()
+		h.Write([]byte(testdata))
+		return (pkg.Checksum)(h.Sum(nil))
+	}()
+
+	var transport http.Transport
+	client := http.Client{Transport: &transport}
+	transport.RegisterProtocol("file", http.NewFileTransportFS(fstest.MapFS{
+		"testdata": {Data: []byte(testdata), Mode: 0400},
+	}))
+
+	checkWithCache(t, []cacheTestCase{
+		{"http", nil, func(t *testing.T, base *check.Absolute, c *pkg.Cache) {
+			wantIdent := func() pkg.ID {
+				h := sha512.New384()
+				h.Write([]byte{byte(pkg.KindTar), 0, 0, 0, 0, 0, 0, 0})
+				h.Write([]byte{pkg.TarGzip, 0, 0, 0, 0, 0, 0, 0})
+				h.Write([]byte{byte(pkg.KindHTTP), 0, 0, 0, 0, 0, 0, 0})
+				h.Write(testdataChecksum[:])
+				return pkg.ID(h.Sum(nil))
+			}()
+
+			a, err := c.NewHTTPGetTar(
+				t.Context(),
+				&client,
+				"file:///testdata",
+				testdataChecksum,
+				pkg.TarGzip,
+			)
+
+			if err != nil {
+				t.Fatalf("NewHTTPGetTar: error = %v", err)
+			} else if id := a.ID(); id != wantIdent {
+				t.Fatalf("ID: %s, want %s", pkg.Encode(id), pkg.Encode(wantIdent))
+			}
+
+			var pathname *check.Absolute
+			wantPathname := base.Append(
+				"identifier",
+				pkg.Encode(wantIdent),
+			)
+			if pathname, err = a.Pathname(); err != nil {
+				t.Fatalf("Pathname: error = %v", err)
+			} else if !pathname.Is(wantPathname) {
+				t.Fatalf("Pathname: %q, want %q", pathname, wantPathname)
+			}
+
+			var checksum pkg.Checksum
+			wantChecksum := pkg.MustDecode("yJlSb2A3jxaMLuKqwp1GwHOguAHddS9MjygF9ICEeegKfRvgLPdPmNh8mva47f8o")
+			if checksum, err = a.Hash(); err != nil {
+				t.Fatalf("Hash: error = %v", err)
+			} else if checksum != wantChecksum {
+				t.Fatalf("Hash: %v", &pkg.ChecksumMismatchError{
+					Got:  checksum,
+					Want: wantChecksum,
+				})
+			}
+		}, pkg.MustDecode("p1HdTOQhIeWzpXdZ45xo00H9CFeXNIvazxOhBAfExlhFO64zt7TUbxoLJ2eAL5oc")},
+	})
+}