layer_test.go

Documentation: github.com/google/go-containerregistry/pkg/v1/stream

     1  // Copyright 2018 Google LLC All Rights Reserved.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //    http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package stream
    16  
    17  import (
    18  	"archive/tar"
    19  	"bytes"
    20  	"crypto/rand"
    21  	"errors"
    22  	"fmt"
    23  	"io"
    24  	"strings"
    25  	"testing"
    26  
    27  	v1 "github.com/google/go-containerregistry/pkg/v1"
    28  	"github.com/google/go-containerregistry/pkg/v1/tarball"
    29  	"github.com/google/go-containerregistry/pkg/v1/types"
    30  )
    31  
    32  func TestStreamVsBuffer(t *testing.T) {
    33  	var n, wantSize int64 = 10000, 49
    34  	newBlob := func() io.ReadCloser { return io.NopCloser(bytes.NewReader(bytes.Repeat([]byte{'a'}, int(n)))) }
    35  	wantDigest := "sha256:3d7c465be28d9e1ed810c42aeb0e747b44441424f566722ba635dc93c947f30e"
    36  	wantDiffID := "sha256:27dd1f61b867b6a0f6e9d8a41c43231de52107e53ae424de8f847b821db4b711"
    37  
    38  	// Check that streaming some content results in the expected digest/diffID/size.
    39  	l := NewLayer(newBlob())
    40  	if c, err := l.Compressed(); err != nil {
    41  		t.Errorf("Compressed: %v", err)
    42  	} else {
    43  		if _, err := io.Copy(io.Discard, c); err != nil {
    44  			t.Errorf("error reading Compressed: %v", err)
    45  		}
    46  		if err := c.Close(); err != nil {
    47  			t.Errorf("Close: %v", err)
    48  		}
    49  	}
    50  	if d, err := l.Digest(); err != nil {
    51  		t.Errorf("Digest: %v", err)
    52  	} else if d.String() != wantDigest {
    53  		t.Errorf("stream Digest got %q, want %q", d.String(), wantDigest)
    54  	}
    55  	if d, err := l.DiffID(); err != nil {
    56  		t.Errorf("DiffID: %v", err)
    57  	} else if d.String() != wantDiffID {
    58  		t.Errorf("stream DiffID got %q, want %q", d.String(), wantDiffID)
    59  	}
    60  	if s, err := l.Size(); err != nil {
    61  		t.Errorf("Size: %v", err)
    62  	} else if s != wantSize {
    63  		t.Errorf("stream Size got %d, want %d", s, wantSize)
    64  	}
    65  
    66  	// Test that buffering the same contents and using
    67  	// tarball.LayerFromOpener results in the same digest/diffID/size.
    68  	tl, err := tarball.LayerFromOpener(func() (io.ReadCloser, error) { return newBlob(), nil })
    69  	if err != nil {
    70  		t.Fatalf("LayerFromOpener: %v", err)
    71  	}
    72  	if d, err := tl.Digest(); err != nil {
    73  		t.Errorf("Digest: %v", err)
    74  	} else if d.String() != wantDigest {
    75  		t.Errorf("tarball Digest got %q, want %q", d.String(), wantDigest)
    76  	}
    77  	if d, err := tl.DiffID(); err != nil {
    78  		t.Errorf("DiffID: %v", err)
    79  	} else if d.String() != wantDiffID {
    80  		t.Errorf("tarball DiffID got %q, want %q", d.String(), wantDiffID)
    81  	}
    82  	if s, err := tl.Size(); err != nil {
    83  		t.Errorf("Size: %v", err)
    84  	} else if s != wantSize {
    85  		t.Errorf("stream Size got %d, want %d", s, wantSize)
    86  	}
    87  
    88  	// Test with different compression
    89  	l2 := NewLayer(newBlob(), WithCompressionLevel(2))
    90  	l2WantDigest := "sha256:c9afe7b0da6783232e463e12328cb306142548384accf3995806229c9a6a707f"
    91  	if c, err := l2.Compressed(); err != nil {
    92  		t.Errorf("Compressed: %v", err)
    93  	} else {
    94  		if _, err := io.Copy(io.Discard, c); err != nil {
    95  			t.Errorf("error reading Compressed: %v", err)
    96  		}
    97  		if err := c.Close(); err != nil {
    98  			t.Errorf("Close: %v", err)
    99  		}
   100  	}
   101  	if d, err := l2.Digest(); err != nil {
   102  		t.Errorf("Digest: %v", err)
   103  	} else if d.String() != l2WantDigest {
   104  		t.Errorf("stream Digest got %q, want %q", d.String(), l2WantDigest)
   105  	}
   106  }
   107  
   108  func TestLargeStream(t *testing.T) {
   109  	var n, wantSize int64 = 10000000, 10000788 // "Compressing" n random bytes results in this many bytes.
   110  	sl := NewLayer(io.NopCloser(io.LimitReader(rand.Reader, n)))
   111  	rc, err := sl.Compressed()
   112  	if err != nil {
   113  		t.Fatalf("Uncompressed: %v", err)
   114  	}
   115  	if _, err := io.Copy(io.Discard, rc); err != nil {
   116  		t.Fatalf("Reading layer: %v", err)
   117  	}
   118  	if err := rc.Close(); err != nil {
   119  		t.Fatalf("Close: %v", err)
   120  	}
   121  
   122  	if dig, err := sl.Digest(); err != nil {
   123  		t.Errorf("Digest: %v", err)
   124  	} else if dig.String() == (v1.Hash{}).String() {
   125  		t.Errorf("Digest got %q, want anything else", (v1.Hash{}).String())
   126  	}
   127  	if diffID, err := sl.DiffID(); err != nil {
   128  		t.Errorf("DiffID: %v", err)
   129  	} else if diffID.String() == (v1.Hash{}).String() {
   130  		t.Errorf("DiffID got %q, want anything else", (v1.Hash{}).String())
   131  	}
   132  	if size, err := sl.Size(); err != nil {
   133  		t.Errorf("Size: %v", err)
   134  	} else if size != wantSize {
   135  		t.Errorf("Size got %d, want %d", size, wantSize)
   136  	}
   137  }
   138  
   139  func TestStreamableLayerFromTarball(t *testing.T) {
   140  	pr, pw := io.Pipe()
   141  	tw := tar.NewWriter(pw)
   142  	go func() {
   143  		// "Stream" a bunch of files into the layer.
   144  		pw.CloseWithError(func() error {
   145  			for i := 0; i < 1000; i++ {
   146  				name := fmt.Sprintf("file-%d.txt", i)
   147  				body := fmt.Sprintf("i am file number %d", i)
   148  				if err := tw.WriteHeader(&tar.Header{
   149  					Name:     name,
   150  					Mode:     0600,
   151  					Size:     int64(len(body)),
   152  					Typeflag: tar.TypeReg,
   153  				}); err != nil {
   154  					return err
   155  				}
   156  				if _, err := tw.Write([]byte(body)); err != nil {
   157  					return err
   158  				}
   159  			}
   160  			return tw.Close()
   161  		}())
   162  	}()
   163  
   164  	l := NewLayer(pr)
   165  	rc, err := l.Compressed()
   166  	if err != nil {
   167  		t.Fatalf("Compressed: %v", err)
   168  	}
   169  	if _, err := io.Copy(io.Discard, rc); err != nil {
   170  		t.Fatalf("Copy: %v", err)
   171  	}
   172  	if err := rc.Close(); err != nil {
   173  		t.Fatalf("Close: %v", err)
   174  	}
   175  
   176  	wantDigest := "sha256:ed80efd7e7e884fb59db568f234332283b341b96155e872d638de42d55a34198"
   177  	if got, err := l.Digest(); err != nil {
   178  		t.Errorf("Digest: %v", err)
   179  	} else if got.String() != wantDigest {
   180  		t.Errorf("Digest: got %q, want %q", got.String(), wantDigest)
   181  	}
   182  }
   183  
   184  // TestNotComputed tests that Digest/DiffID/Size return ErrNotComputed before
   185  // the stream has been consumed.
   186  func TestNotComputed(t *testing.T) {
   187  	l := NewLayer(io.NopCloser(bytes.NewBufferString("hi")))
   188  
   189  	// All methods should return ErrNotComputed until the stream has been
   190  	// consumed and closed.
   191  	if _, err := l.Size(); !errors.Is(err, ErrNotComputed) {
   192  		t.Errorf("Size: got %v, want %v", err, ErrNotComputed)
   193  	}
   194  	if _, err := l.Digest(); err == nil {
   195  		t.Errorf("Digest: got %v, want %v", err, ErrNotComputed)
   196  	}
   197  	if _, err := l.DiffID(); err == nil {
   198  		t.Errorf("DiffID: got %v, want %v", err, ErrNotComputed)
   199  	}
   200  }
   201  
   202  // TestConsumed tests that Compressed returns ErrConsumed when the stream has
   203  // already been consumed.
   204  func TestConsumed(t *testing.T) {
   205  	l := NewLayer(io.NopCloser(strings.NewReader("hello")))
   206  	rc, err := l.Compressed()
   207  	if err != nil {
   208  		t.Errorf("Compressed: %v", err)
   209  	}
   210  	if _, err := io.Copy(io.Discard, rc); err != nil {
   211  		t.Errorf("Error reading contents: %v", err)
   212  	}
   213  	if err := rc.Close(); err != nil {
   214  		t.Errorf("Close: %v", err)
   215  	}
   216  
   217  	if _, err := l.Compressed(); !errors.Is(err, ErrConsumed) {
   218  		t.Errorf("Compressed() after consuming; got %v, want %v", err, ErrConsumed)
   219  	}
   220  }
   221  
   222  func TestCloseTextStreamBeforeConsume(t *testing.T) {
   223  	// Create stream layer from tar pipe
   224  	l := NewLayer(io.NopCloser(strings.NewReader("hello")))
   225  	rc, err := l.Compressed()
   226  	if err != nil {
   227  		t.Fatalf("Compressed: %v", err)
   228  	}
   229  
   230  	// Close stream layer before consuming
   231  	if err := rc.Close(); err != nil {
   232  		t.Fatalf("Close: %v", err)
   233  	}
   234  }
   235  
   236  func TestCloseTarStreamBeforeConsume(t *testing.T) {
   237  	// Write small tar to pipe
   238  	pr, pw := io.Pipe()
   239  	tw := tar.NewWriter(pw)
   240  	go func() {
   241  		pw.CloseWithError(func() error {
   242  			body := "test file"
   243  			if err := tw.WriteHeader(&tar.Header{
   244  				Name:     "test.txt",
   245  				Mode:     0600,
   246  				Size:     int64(len(body)),
   247  				Typeflag: tar.TypeReg,
   248  			}); err != nil {
   249  				return err
   250  			}
   251  			if _, err := tw.Write([]byte(body)); err != nil {
   252  				return err
   253  			}
   254  			return tw.Close()
   255  		}())
   256  	}()
   257  
   258  	// Create stream layer from tar pipe
   259  	l := NewLayer(pr)
   260  	rc, err := l.Compressed()
   261  	if err != nil {
   262  		t.Fatalf("Compressed: %v", err)
   263  	}
   264  
   265  	// Close stream layer before consuming
   266  	if err := rc.Close(); err != nil {
   267  		t.Fatalf("Close: %v", err)
   268  	}
   269  }
   270  
   271  func TestMediaType(t *testing.T) {
   272  	l := NewLayer(io.NopCloser(strings.NewReader("hello")))
   273  	mediaType, err := l.MediaType()
   274  
   275  	if err != nil {
   276  		t.Fatalf("MediaType(): %v", err)
   277  	}
   278  
   279  	if got, want := mediaType, types.DockerLayer; got != want {
   280  		t.Errorf("MediaType(): want %q, got %q", want, got)
   281  	}
   282  }
   283  
   284  func TestMediaTypeOption(t *testing.T) {
   285  	l := NewLayer(io.NopCloser(strings.NewReader("hello")), WithMediaType(types.OCILayer))
   286  	mediaType, err := l.MediaType()
   287  
   288  	if err != nil {
   289  		t.Fatalf("MediaType(): %v", err)
   290  	}
   291  
   292  	if got, want := mediaType, types.OCILayer; got != want {
   293  		t.Errorf("MediaType(): want %q, got %q", want, got)
   294  	}
   295  }
   296
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