|
| 1 | +package test |
| 2 | + |
| 3 | +import ( |
| 4 | + "bytes" |
| 5 | + "context" |
| 6 | + "io" |
| 7 | + "testing" |
| 8 | + |
| 9 | + u "github.com/ipfs/go-ipfs-util" |
| 10 | + "github.com/ipfs/go-unixfsnode/data/builder" |
| 11 | + "github.com/ipfs/go-unixfsnode/file" |
| 12 | + dagpb "github.com/ipld/go-codec-dagpb" |
| 13 | + "github.com/ipld/go-ipld-prime" |
| 14 | + "github.com/ipld/go-ipld-prime/datamodel" |
| 15 | + "github.com/ipld/go-ipld-prime/linking" |
| 16 | + cidlink "github.com/ipld/go-ipld-prime/linking/cid" |
| 17 | + basicnode "github.com/ipld/go-ipld-prime/node/basic" |
| 18 | + "github.com/ipld/go-ipld-prime/traversal" |
| 19 | + sb "github.com/ipld/go-ipld-prime/traversal/selector/builder" |
| 20 | +) |
| 21 | + |
| 22 | +func TestPartialFileAccess(t *testing.T) { |
| 23 | + buf := make([]byte, 10*1024*1024) |
| 24 | + u.NewSeededRand(0xdeadbeef).Read(buf) |
| 25 | + r := bytes.NewReader(buf) |
| 26 | + |
| 27 | + ls := cidlink.DefaultLinkSystem() |
| 28 | + storage := cidlink.Memory{} |
| 29 | + ls.StorageReadOpener = storage.OpenRead |
| 30 | + ls.StorageWriteOpener = storage.OpenWrite |
| 31 | + |
| 32 | + f, _, err := builder.BuildUnixFSFile(r, "", &ls) |
| 33 | + if err != nil { |
| 34 | + t.Fatal(err) |
| 35 | + } |
| 36 | + |
| 37 | + // get back the root node substrate from the link at the top of the builder. |
| 38 | + fr, err := ls.Load(ipld.LinkContext{}, f, dagpb.Type.PBNode) |
| 39 | + if err != nil { |
| 40 | + t.Fatal(err) |
| 41 | + } |
| 42 | + |
| 43 | + ufn, err := file.NewUnixFSFile(context.Background(), fr, &ls) |
| 44 | + if err != nil { |
| 45 | + t.Fatal(err) |
| 46 | + } |
| 47 | + |
| 48 | + openedLinks := []ipld.Link{} |
| 49 | + ls.StorageReadOpener = func(lc linking.LinkContext, l datamodel.Link) (io.Reader, error) { |
| 50 | + openedLinks = append(openedLinks, l) |
| 51 | + return storage.OpenRead(lc, l) |
| 52 | + } |
| 53 | + |
| 54 | + // read back out the file. |
| 55 | + out, err := ufn.AsBytes() |
| 56 | + if err != nil { |
| 57 | + t.Fatal(err) |
| 58 | + } |
| 59 | + if !bytes.Equal(out, buf) { |
| 60 | + t.Fatal("Not equal") |
| 61 | + } |
| 62 | + |
| 63 | + fullLen := len(openedLinks) |
| 64 | + |
| 65 | + openedLinks = []ipld.Link{} |
| 66 | + |
| 67 | + partial, err := ufn.(datamodel.LargeBytesNode).AsLargeBytes() |
| 68 | + if err != nil { |
| 69 | + t.Fatal(err) |
| 70 | + } |
| 71 | + half := make([]byte, len(buf)/2) |
| 72 | + if _, err := partial.Read(half); err != nil { |
| 73 | + t.Fatal(err) |
| 74 | + } |
| 75 | + if len(openedLinks) >= fullLen { |
| 76 | + t.Fatal("should not have accessed full file on a partial read.") |
| 77 | + } |
| 78 | + |
| 79 | + openedLinks = []ipld.Link{} |
| 80 | + |
| 81 | + prog := traversal.Progress{ |
| 82 | + Cfg: &traversal.Config{ |
| 83 | + LinkSystem: ls, |
| 84 | + }, |
| 85 | + } |
| 86 | + sb := sb.NewSelectorSpecBuilder(basicnode.Prototype.Any) |
| 87 | + ss := sb.MatcherSubset(5*1024*1024, 6*1024*1024) |
| 88 | + sel, err := ss.Selector() |
| 89 | + if err != nil { |
| 90 | + t.Fatal(err) |
| 91 | + } |
| 92 | + |
| 93 | + if err := prog.WalkMatching(ufn, sel, func(_ traversal.Progress, n datamodel.Node) error { |
| 94 | + b, err := n.AsBytes() |
| 95 | + if err != nil { |
| 96 | + t.Fatal(err) |
| 97 | + } |
| 98 | + if len(b) != 1024*1024 { |
| 99 | + t.Fatalf("wrong length: %d", len(b)) |
| 100 | + } |
| 101 | + return nil |
| 102 | + }); err != nil { |
| 103 | + t.Fatal(err) |
| 104 | + } |
| 105 | + if len(openedLinks) >= fullLen { |
| 106 | + t.Fatal("should not have accessed full file on a partial traversal.") |
| 107 | + } |
| 108 | +} |
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