Download files without padding (#218)

The initial goal of this patch was to allow to download of a file via REST API in exactly the same size as it was uploaded, which required adding fields Chunker.offset and Manifest.originalBytes to keep that size. On top of that, we added more integrity checks to operations on Manifest, and reorganized TestNode.nim to test the actual interaction between node.store and node.retrieve operations.

Note that the wire format of Manifest was changed, so we need to recreate all BlockStores.

* Download without padding
* Fixed chunker tests
* Chunker: get rid of RabinChunker
* Verify offset in the chunker tests
* Use manifest.originalBytesPadded in StoreStream.size
* StoreStream: replace emptyBlock with zeroMem
* Manifest.bytes: compute how many bytes corresponding StoreStream(Manifest, pad) will return
* Manifest: verify originalBytes and originalLen on new/encode/decode
Also set originalBytes in each Manifest creation/update scenario
* Manifest: comments, split code into sections
* Reordered parameters to deal with int64 size in 32-bit builds
* TestNode.nim: combine Store and Retrieve tests
1. Instead of copy-pasting code from node.nim, new test calls node.store() and node.retrieve() in order to check that they can correctly store and then retrieve data
2. New test compares only file contents, manifest contents considered an implementation detail
3. New test chunks at odd chunkSize=BlockSize/1.618 in order to ensure that data retrieved correctly even when buffer sizes mismatch
* TestNode.nim: code refactoring
* Manifest.add: one more test
* Manifest.verify: return Result instead of raising Defect
* Node.store: added blockSize parameter

codex/chunker.nim

@@ -29,21 +29,14 @@ const
 type
   # default reader type
   ChunkBuffer* = ptr UncheckedArray[byte]
-  Reader* =
+  Reader* = proc(data: ChunkBuffer, len: int): Future[int] {.gcsafe, raises: [Defect].}
-    proc(data: ChunkBuffer, len: int): Future[int] {.gcsafe, raises: [Defect].}
 
-  ChunkerType* {.pure.} = enum
+  # Reader that splits input data into fixed-size chunks
-    FixedChunker
+  Chunker* = ref object
-    RabinChunker
+    reader*: Reader             # Procedure called to actually read the data
-
+    offset*: int                # Bytes read so far (position in the stream)
-  Chunker* = object
+    chunkSize*: Natural         # Size of each chunk
-    reader*: Reader
+    pad*: bool                  # Pad last chunk to chunkSize?
-    case kind*: ChunkerType:
-    of FixedChunker:
-      chunkSize*: Natural
-      pad*: bool # pad last block if less than size
-    of RabinChunker:
-      discard
 
   FileChunker* = Chunker
   LPStreamChunker* = Chunker
@@ -59,6 +52,8 @@ proc getBytes*(c: Chunker): Future[seq[byte]] {.async.} =
   if read <= 0:
     return @[]
 
+  c.offset += read
+
   if not c.pad and buff.len > read:
     buff.setLen(read)
 
@@ -66,24 +61,18 @@ proc getBytes*(c: Chunker): Future[seq[byte]] {.async.} =
 
 func new*(
   T: type Chunker,
-  kind = ChunkerType.FixedChunker,
   reader: Reader,
   chunkSize = DefaultChunkSize,
   pad = true): T =
-  var chunker = Chunker(
-    kind: kind,
-    reader: reader)
 
-  if kind == ChunkerType.FixedChunker:
+  T(reader: reader,
-    chunker.pad = pad
+    offset: 0,
-    chunker.chunkSize = chunkSize
+    chunkSize: chunkSize,
-
+    pad: pad)
-  return chunker
 
 proc new*(
   T: type LPStreamChunker,
   stream: LPStream,
-  kind = ChunkerType.FixedChunker,
   chunkSize = DefaultChunkSize,
   pad = true): T =
   ## create the default File chunker
@@ -103,16 +92,14 @@ proc new*(
 
     return res
 
-  Chunker.new(
+  T.new(
-    kind = ChunkerType.FixedChunker,
     reader = reader,
-    pad = pad,
+    chunkSize = chunkSize,
-    chunkSize = chunkSize)
+    pad = pad)
 
 proc new*(
   T: type FileChunker,
   file: File,
-  kind = ChunkerType.FixedChunker,
   chunkSize = DefaultChunkSize,
   pad = true): T =
   ## create the default File chunker
@@ -136,8 +123,7 @@ proc new*(
 
     return total
 
-  Chunker.new(
+  T.new(
-    kind = ChunkerType.FixedChunker,
     reader = reader,
-    pad = pad,
+    chunkSize = chunkSize,
-    chunkSize = chunkSize)
+    pad = pad)

codex/manifest/coders.nim

@@ -7,6 +7,8 @@
 ## This file may not be copied, modified, or distributed except according to
 ## those terms.
 
+# This module implements serialization and deserialization of Manifest
+
 import pkg/upraises
 
 push: {.upraises: [].}
@@ -29,6 +31,7 @@ func encode*(_: DagPBCoder, manifest: Manifest): ?!seq[byte] =
   ## multicodec container (Dag-pb) for now
   ##
 
+  ? manifest.verify()
   var pbNode = initProtoBuffer()
 
   for c in manifest.blocks:
@@ -52,6 +55,7 @@ func encode*(_: DagPBCoder, manifest: Manifest): ?!seq[byte] =
   #     optional uint32 blockSize = 2;    # size of a single block
   #     optional uint32 blocksLen = 3;    # total amount of blocks
   #     optional ErasureInfo erasure = 4; # erasure coding info
+  #     optional uint64 originalBytes = 5;# exact file size
   #   }
   # ```
   #
@@ -61,6 +65,7 @@ func encode*(_: DagPBCoder, manifest: Manifest): ?!seq[byte] =
   header.write(1, cid.data.buffer)
   header.write(2, manifest.blockSize.uint32)
   header.write(3, manifest.len.uint32)
+  header.write(5, manifest.originalBytes.uint64)
   if manifest.protected:
     var erasureInfo = initProtoBuffer()
     erasureInfo.write(1, manifest.K.uint32)
@@ -86,6 +91,7 @@ func decode*(_: DagPBCoder, data: openArray[byte]): ?!Manifest =
     pbErasureInfo: ProtoBuffer
     rootHash: seq[byte]
     originalCid: seq[byte]
+    originalBytes: uint64
     blockSize: uint32
     blocksLen: uint32
     originalLen: uint32
@@ -106,6 +112,9 @@ func decode*(_: DagPBCoder, data: openArray[byte]): ?!Manifest =
   if pbHeader.getField(3, blocksLen).isErr:
     return failure("Unable to decode `blocksLen` from manifest!")
 
+  if pbHeader.getField(5, originalBytes).isErr:
+    return failure("Unable to decode `originalBytes` from manifest!")
+
   if pbHeader.getField(4, pbErasureInfo).isErr:
     return failure("Unable to decode `erasureInfo` from manifest!")
 
@@ -140,6 +149,7 @@ func decode*(_: DagPBCoder, data: openArray[byte]): ?!Manifest =
   var
     self = Manifest(
       rootHash: rootHashCid.some,
+      originalBytes: originalBytes.int,
       blockSize: blockSize.int,
       blocks: blocks,
       hcodec: (? rootHashCid.mhash.mapFailure).mcodec,
@@ -153,6 +163,7 @@ func decode*(_: DagPBCoder, data: openArray[byte]): ?!Manifest =
     self.originalCid = ? Cid.init(originalCid).mapFailure
     self.originalLen = originalLen.int
 
+  ? self.verify()
   self.success
 
 proc encode*(

codex/manifest/manifest.nim

@@ -7,6 +7,8 @@
 ## This file may not be copied, modified, or distributed except according to
 ## those terms.
 
+# This module defines all operations on Manifest
+
 import pkg/upraises
 
 push: {.upraises: [].}
@@ -18,16 +20,18 @@ import pkg/questionable/results
 import pkg/chronicles
 
 import ../errors
+import ../utils
 import ../blocktype
 import ./types
 import ./coders
 
+############################################################
+# Operations on block list
+############################################################
+
 func len*(self: Manifest): int =
   self.blocks.len
 
-func size*(self: Manifest): int =
-  self.blocks.len * self.blockSize
-
 func `[]`*(self: Manifest, i: Natural): Cid =
   self.blocks[i]
 
@@ -43,9 +47,11 @@ func `[]=`*(self: Manifest, i: BackwardsIndex, item: Cid) =
   self.blocks[self.len - i.int] = item
 
 proc add*(self: Manifest, cid: Cid) =
+  assert not self.protected  # we expect that protected manifests are created with properly-sized self.blocks
   self.rootHash = Cid.none
   trace "Adding cid to manifest", cid
   self.blocks.add(cid)
+  self.originalBytes = self.blocks.len * self.blockSize
 
 iterator items*(self: Manifest): Cid =
   for b in self.blocks:
@@ -58,6 +64,44 @@ iterator pairs*(self: Manifest): tuple[key: int, val: Cid] =
 func contains*(self: Manifest, cid: Cid): bool =
   cid in self.blocks
 
+
+############################################################
+# Various sizes and verification
+############################################################
+
+func bytes*(self: Manifest, pad = true): int =
+  ## Compute how many bytes corresponding StoreStream(Manifest, pad) will return
+  if pad or self.protected:
+    self.len * self.blockSize
+  else:
+    self.originalBytes
+
+func rounded*(self: Manifest): int =
+  ## Number of data blocks in *protected* manifest including padding at the end
+  roundUp(self.originalLen, self.K)
+
+func steps*(self: Manifest): int =
+  ## Number of EC groups in *protected* manifest
+  divUp(self.originalLen, self.K)
+
+func verify*(self: Manifest): ?!void =
+  ## Check manifest correctness
+  ##
+  let originalLen = (if self.protected: self.originalLen else: self.len)
+
+  if divUp(self.originalBytes, self.blockSize) != originalLen:
+    return failure newException(CodexError, "Broken manifest: wrong originalBytes")
+
+  if self.protected and (self.len != self.steps * (self.K + self.M)):
+    return failure newException(CodexError, "Broken manifest: wrong originalLen")
+
+  return success()
+
+
+############################################################
+# Cid computation
+############################################################
+
 template hashBytes(mh: MultiHash): seq[byte] =
   ## get the hash bytes of a multihash object
   ##
@@ -95,15 +139,6 @@ proc makeRoot*(self: Manifest): ?!void =
 
   success()
 
-func rounded*(self: Manifest): int =
-  if (self.originalLen mod self.K) != 0:
-    return self.originalLen + (self.K - (self.originalLen mod self.K))
-
-  self.originalLen
-
-func steps*(self: Manifest): int =
-  self.rounded div self.K # number of blocks per row
-
 proc cid*(self: Manifest): ?!Cid =
   ## Generate a root hash using the treehash algorithm
   ##
@@ -113,6 +148,11 @@ proc cid*(self: Manifest): ?!Cid =
 
   (!self.rootHash).success
 
+
+############################################################
+# Constructors
+############################################################
+
 proc new*(
   T: type Manifest,
   blocks: openArray[Cid] = [],
@@ -133,6 +173,7 @@ proc new*(
     codec: codec,
     hcodec: hcodec,
     blockSize: blockSize,
+    originalBytes: blocks.len * blockSize,
     protected: protected).success
 
 proc new*(
@@ -148,6 +189,7 @@ proc new*(
       version: manifest.version,
       codec: manifest.codec,
       hcodec: manifest.hcodec,
+      originalBytes: manifest.originalBytes,
       blockSize: manifest.blockSize,
       protected: true,
       K: K, M: M,
@@ -170,6 +212,7 @@ proc new*(
       .catch
       .get()
 
+  ? self.verify()
   self.success
 
 proc new*(

codex/manifest/types.nim

@@ -7,6 +7,8 @@
 ## This file may not be copied, modified, or distributed except according to
 ## those terms.
 
+# This module defines Manifest and all related types
+
 import std/tables
 import pkg/libp2p
 import pkg/questionable
@@ -25,9 +27,10 @@ const
 
 type
   Manifest* = ref object of RootObj
-    rootHash*: ?Cid         # root (tree) hash of the contained data set
+    rootHash*: ?Cid         # Root (tree) hash of the contained data set
-    blockSize*: int         # size of each contained block (might not be needed if blocks are len-prefixed)
+    originalBytes*: int     # Exact size of the original (uploaded) file
-    blocks*: seq[Cid]       # block Cid
+    blockSize*: int         # Size of each contained block (might not be needed if blocks are len-prefixed)
+    blocks*: seq[Cid]       # Block Cid
     version*: CidVersion    # Cid version
     hcodec*: MultiCodec     # Multihash codec
     codec*: MultiCodec      # Data set codec

codex/node.nim

@@ -115,28 +115,33 @@ proc fetchBatched*(
 proc retrieve*(
   node: CodexNodeRef,
   cid: Cid): Future[?!LPStream] {.async.} =
-  ## Retrieve a block or manifest
+  ## Retrieve by Cid a single block or an entire dataset described by manifest
   ##
 
   if manifest =? (await node.fetchManifest(cid)):
     if manifest.protected:
+      # Retrieve, decode and save to the local store all EС groups
       proc erasureJob(): Future[void] {.async.} =
         try:
-          without res =? (await node.erasure.decode(manifest)), error: # spawn an erasure decoding job
+          # Spawn an erasure decoding job
+          without res =? (await node.erasure.decode(manifest)), error:
             trace "Unable to erasure decode manifest", cid, exc = error.msg
         except CatchableError as exc:
           trace "Exception decoding manifest", cid
-
+      #
       asyncSpawn erasureJob()
     else:
+      # Prefetch the entire dataset into the local store
       proc prefetchBlocks() {.async, raises: [Defect].} =
         try:
           discard await node.fetchBatched(manifest)
         except CatchableError as exc:
           trace "Exception prefetching blocks", exc = exc.msg
-
+      #
       asyncSpawn prefetchBlocks()
-    return LPStream(StoreStream.new(node.blockStore, manifest)).success
+    #
+    # Retrieve all blocks of the dataset sequentially from the local store or network
+    return LPStream(StoreStream.new(node.blockStore, manifest, pad = false)).success
 
   let
     stream = BufferStream.new()
@@ -158,14 +163,18 @@ proc retrieve*(
 
 proc store*(
   node: CodexNodeRef,
-  stream: LPStream): Future[?!Cid] {.async.} =
+  stream: LPStream,
+  blockSize = BlockSize): Future[?!Cid] {.async.} =
+  ## Save stream contents as dataset with given blockSize
+  ## to nodes's BlockStore, and return Cid of its manifest
+  ##
   trace "Storing data"
 
-  without var blockManifest =? Manifest.new():
+  without var blockManifest =? Manifest.new(blockSize = blockSize):
     return failure("Unable to create Block Set")
 
-  let
+  # Manifest and chunker should use the same blockSize
-    chunker = LPStreamChunker.new(stream, chunkSize = BlockSize)
+  let chunker = LPStreamChunker.new(stream, chunkSize = blockSize)
 
   try:
     while (
@@ -189,6 +198,7 @@ proc store*(
     await stream.close()
 
   # Generate manifest
+  blockManifest.originalBytes = chunker.offset  # store the exact file size
   without data =? blockManifest.encode():
     return failure(
       newException(CodexError, "Could not generate dataset manifest!"))

codex/streams/storestream.nim

@@ -30,25 +30,29 @@ logScope:
   topics = "dagger storestream"
 
 type
+  # Make SeekableStream from a sequence of blocks stored in Manifest
+  # (only original file data - see StoreStream.size)
   StoreStream* = ref object of SeekableStream
-    store*: BlockStore
+    store*: BlockStore          # Store where to lookup block contents
-    manifest*: Manifest
+    manifest*: Manifest         # List of block CIDs
-    emptyBlock*: seq[byte]
+    pad*: bool                  # Pad last block to manifest.blockSize?
 
 proc new*(
   T: type StoreStream,
   store: BlockStore,
-  manifest: Manifest): T =
+  manifest: Manifest,
+  pad = true): T =
+
   result = T(
     store: store,
     manifest: manifest,
-    offset: 0,
+    pad: pad,
-    emptyBlock: newSeq[byte](manifest.blockSize))
+    offset: 0)
 
   result.initStream()
 
 method `size`*(self: StoreStream): int =
-  self.manifest.len * self.manifest.blockSize
+  bytes(self.manifest, self.pad)
 
 proc `size=`*(self: StoreStream, size: int)
   {.error: "Setting the size is forbidden".} =
@@ -78,7 +82,7 @@ method readOnce*(
     let
       blockNum    = self.offset div self.manifest.blockSize
       blockOffset = self.offset mod self.manifest.blockSize
-      readBytes   = min(nbytes - read, self.manifest.blockSize - blockOffset)
+      readBytes   = min([self.size - self.offset, nbytes - read, self.manifest.blockSize - blockOffset])
 
     # Read contents of block `blockNum`
     without blk =? await self.store.getBlock(self.manifest[blockNum]), error:
@@ -87,13 +91,10 @@ method readOnce*(
     trace "Reading bytes from store stream", blockNum, cid = blk.cid, bytes = readBytes, blockOffset
 
     # Copy `readBytes` bytes starting at `blockOffset` from the block into the outbuf
-    copyMem(
-      pbytes.offset(read),
     if blk.isEmpty:
-          self.emptyBlock[blockOffset].addr
+      zeroMem(pbytes.offset(read), readBytes)
     else:
-          blk.data[blockOffset].addr,
+      copyMem(pbytes.offset(read), blk.data[blockOffset].addr, readBytes)
-      readBytes)
 
     # Update current positions in the stream and outbuf
     self.offset += readBytes
@@ -102,12 +103,6 @@ method readOnce*(
   return read
 
 method closeImpl*(self: StoreStream) {.async.} =
-  try:
   trace "Closing StoreStream"
-    self.offset = self.manifest.len * self.manifest.blockSize # set Eof
+  self.offset = self.size  # set Eof
-  except CancelledError as exc:
-    raise exc
-  except CatchableError as exc:
-    trace "Error closing StoreStream", msg = exc.msg
-
   await procCall LPStream(self).closeImpl()

codex/utils.nim

@@ -2,3 +2,14 @@ import ./utils/asyncheapqueue
 import ./utils/fileutils
 
 export asyncheapqueue, fileutils
+
+
+func divUp*[T](a, b : T): T =
+  ## Division with result rounded up (rather than truncated as in 'div')
+  assert(b != 0)
+  if a==0:  0  else:  ((a - 1) div b) + 1
+
+func roundUp*[T](a, b : T): T =
+  ## Round up 'a' to the next value divisible by 'b'
+  divUp(a,b) * b
+

tests/codex/helpers/randomchunker.nim

@@ -13,7 +13,6 @@ type
 proc new*(
   T: type RandomChunker,
   rng: Rng,
-  kind = ChunkerType.FixedChunker,
   chunkSize = DefaultChunkSize,
   size: int,
   pad = false): T =
@@ -43,7 +42,6 @@ proc new*(
     return read
 
   Chunker.new(
-    kind = ChunkerType.FixedChunker,
     reader = reader,
     pad = pad,
     chunkSize = chunkSize)

tests/codex/testchunking.nim

@@ -11,12 +11,14 @@ suite "Chunking":
     let contents = [1.byte, 2, 3, 4, 5, 6, 7, 8, 9, 0]
     proc reader(data: ChunkBuffer, len: int): Future[int]
       {.gcsafe, async, raises: [Defect].} =
-      if offset >= contents.len:
+
+      let read = min(contents.len - offset, len)
+      if read == 0:
         return 0
 
-      copyMem(data, unsafeAddr contents[offset], len)
+      copyMem(data, unsafeAddr contents[offset], read)
-      offset += 2
+      offset += read
-      return len
+      return read
 
     let chunker = Chunker.new(
       reader = reader,
@@ -29,9 +31,9 @@ suite "Chunking":
       (await chunker.getBytes()) == [7.byte, 8]
       (await chunker.getBytes()) == [9.byte, 0]
       (await chunker.getBytes()) == []
+      chunker.offset == offset
 
   test "should chunk LPStream":
-    var offset = 0
     let stream = BufferStream.new()
     let chunker = LPStreamChunker.new(
       stream = stream,
@@ -51,6 +53,7 @@ suite "Chunking":
       (await chunker.getBytes()) == [7.byte, 8]
       (await chunker.getBytes()) == [9.byte, 0]
       (await chunker.getBytes()) == []
+      chunker.offset == 10
 
     await writerFut
 
@@ -69,4 +72,7 @@ suite "Chunking":
       check buff.len <= fileChunker.chunkSize
       data.add(buff)
 
-    check string.fromBytes(data) == readFile(path)
+    check:
+      string.fromBytes(data) == readFile(path)
+      fileChunker.offset == data.len
+

tests/codex/testnode.nim

@@ -1,5 +1,6 @@
 import std/os
 import std/options
+import std/math
 
 import pkg/asynctest
 import pkg/chronos
@@ -39,6 +40,39 @@ suite "Test Node":
     pendingBlocks: PendingBlocksManager
     discovery: DiscoveryEngine
 
+  proc fetch(T: type Manifest, chunker: Chunker): Future[Manifest] {.async.} =
+    # Collect blocks from Chunker into Manifest
+    var
+      manifest = Manifest.new().tryGet()
+
+    while (
+      let chunk = await chunker.getBytes();
+      chunk.len > 0):
+
+      let blk = bt.Block.new(chunk).tryGet()
+      (await localStore.putBlock(blk)).tryGet()
+      manifest.add(blk.cid)
+
+    return manifest
+
+  proc retrieve(cid: Cid): Future[seq[byte]] {.async.} =
+    # Retrieve an entire file contents by file Cid
+    let
+      oddChunkSize = math.trunc(BlockSize/1.359).int  # Let's check that node.retrieve can correctly rechunk data
+      stream = (await node.retrieve(cid)).tryGet()
+    var
+      data: seq[byte]
+
+    while not stream.atEof:
+      var
+        buf = newSeq[byte](oddChunkSize)
+        res = await stream.readOnce(addr buf[0], oddChunkSize)
+      check res <= oddChunkSize
+      buf.setLen(res)
+      data &= buf
+
+    return data
+
   setup:
     file = open(path.splitFile().dir /../ "fixtures" / "test.jpg")
     chunker = FileChunker.new(file = file, chunkSize = BlockSize)
@@ -61,18 +95,9 @@ suite "Test Node":
     await node.stop()
 
   test "Fetch Manifest":
-    var
-      manifest = Manifest.new().tryGet()
-
-    while (
-      let chunk = await chunker.getBytes();
-      chunk.len > 0):
-
-      let blk = bt.Block.new(chunk).tryGet()
-      (await localStore.putBlock(blk)).tryGet()
-      manifest.add(blk.cid)
-
     let
+      manifest = await Manifest.fetch(chunker)
+
       manifestBlock = bt.Block.new(
           manifest.encode().tryGet(),
           codec = DagPBCodec
@@ -88,115 +113,51 @@ suite "Test Node":
       fetched.blocks == manifest.blocks
 
   test "Block Batching":
-    var
-      manifest = Manifest.new().tryGet()
-
-    while (
-      let chunk = await chunker.getBytes();
-      chunk.len > 0):
-
-      let blk = bt.Block.new(chunk).tryGet()
-      (await localStore.putBlock(blk)).tryGet()
-      manifest.add(blk.cid)
-
     let
-      manifestBlock = bt.Block.new(
+      manifest = await Manifest.fetch(chunker)
-          manifest.encode().tryGet(),
-          codec = DagPBCodec
-        ).tryGet()
 
+    for batchSize in 1..12:
       (await node.fetchBatched(
         manifest,
-      batchSize = 3,
+        batchSize = batchSize,
         proc(blocks: seq[bt.Block]) {.gcsafe, async.} =
-        check blocks.len > 0 and blocks.len <= 3
+          check blocks.len > 0 and blocks.len <= batchSize
       )).tryGet()
 
-    (await node.fetchBatched(
+  test "Store and retrieve Data Stream":
-      manifest,
-      batchSize = 6,
-      proc(blocks: seq[bt.Block]) {.gcsafe, async.} =
-        check blocks.len > 0 and blocks.len <= 6
-    )).tryGet()
-
-    (await node.fetchBatched(
-      manifest,
-      batchSize = 9,
-      proc(blocks: seq[bt.Block]) {.gcsafe, async.} =
-        check blocks.len > 0 and blocks.len <= 9
-    )).tryGet()
-
-    (await node.fetchBatched(
-      manifest,
-      batchSize = 11,
-      proc(blocks: seq[bt.Block]) {.gcsafe, async.} =
-        check blocks.len > 0 and blocks.len <= 11
-    )).tryGet()
-
-  test "Store Data Stream":
     let
       stream = BufferStream.new()
       storeFut = node.store(stream)
-
+      oddChunkSize = math.trunc(BlockSize/1.618).int  # Let's check that node.store can correctly rechunk these odd chunks
+      oddChunker = FileChunker.new(file = file, chunkSize = oddChunkSize, pad = false)  # TODO: doesn't work with pad=tue
     var
-      manifest = Manifest.new().tryGet()
+      original: seq[byte]
 
     try:
       while (
-        let chunk = await chunker.getBytes();
+        let chunk = await oddChunker.getBytes();
         chunk.len > 0):
+        original &= chunk
         await stream.pushData(chunk)
-        manifest.add(bt.Block.new(chunk).tryGet().cid)
     finally:
       await stream.pushEof()
       await stream.close()
 
     let
       manifestCid = (await storeFut).tryGet()
-
     check:
       (await localStore.hasBlock(manifestCid)).tryGet()
 
-    var
+    let
       manifestBlock = (await localStore.getBlock(manifestCid)).tryGet()
       localManifest = Manifest.decode(manifestBlock).tryGet()
 
-    check:
-      manifest.len == localManifest.len
-      manifest.cid == localManifest.cid
-
-  test "Retrieve Data Stream":
-    var
-      manifest = Manifest.new().tryGet()
-      original: seq[byte]
-
-    while (
-      let chunk = await chunker.getBytes();
-      chunk.len > 0):
-
-      let blk = bt.Block.new(chunk).tryGet()
-      original &= chunk
-      (await localStore.putBlock(blk)).tryGet()
-      manifest.add(blk.cid)
-
     let
-      manifestBlock = bt.Block.new(
+      data = await retrieve(manifestCid)
-          manifest.encode().tryGet(),
+    check:
-          codec = DagPBCodec
+      data.len == localManifest.originalBytes
-        ).tryGet()
+      data.len == original.len
-
+      sha256.digest(data) == sha256.digest(original)
-    (await localStore.putBlock(manifestBlock)).tryGet()
-
-    let stream = (await node.retrieve(manifestBlock.cid)).tryGet()
-    var data: seq[byte]
-    while not stream.atEof:
-      var
-        buf = newSeq[byte](BlockSize)
-        res = await stream.readOnce(addr buf[0], BlockSize div 2)
-      buf.setLen(res)
-      data &= buf
-
-    check data == original
 
   test "Retrieve One Block":
     let

vendor/questionable

@@ -1 +1 @@
-Subproject commit 82408a5ca2c24eca411d6774cf83816877170627
+Subproject commit 6018fd43e033d5a5310faa45bcaa1b44049469a4