adds protobuf methods for pagination (#248)

tests/v2/test_waku_store.nim

@@ -57,3 +57,106 @@ procSuite "Waku Store":
 
     check:
       (await completionFut.withTimeout(5.seconds)) == true
+
+  test "Index Protobuf encoder/decoder test":
+    let
+      index = computeIndex(WakuMessage(payload: @[byte 1], contentTopic: ContentTopic(1)))
+      pb = index.encode()
+      decodedIndex = Index.init(pb.buffer)
+
+    check:
+      # the fields of decodedIndex must be the same as the original index
+      decodedIndex.isErr == false
+      decodedIndex.value == index
+
+    let
+      emptyIndex = Index()
+      epb = emptyIndex.encode()
+      decodedEmptyIndex = Index.init(epb.buffer)
+
+    check:
+      # check the correctness of init and encode for an empty Index
+      decodedEmptyIndex.isErr == false
+      decodedEmptyIndex.value == emptyIndex
+
+
+  test "PagingDirection Protobuf encod/init test":
+    let
+      pagingDirection = PagingDirection.BACKWARD
+      pb = pagingDirection.encode()
+      decodedPagingDirection = PagingDirection.init(pb.buffer)
+
+    check:
+      # the decodedPagingDirection must be the same as the original pagingDirection
+      decodedPagingDirection.isErr == false
+      decodedPagingDirection.value == pagingDirection
+
+  test "PagingInfo Protobuf encod/init test":
+    let
+      index = computeIndex(WakuMessage(payload: @[byte 1], contentTopic: ContentTopic(1)))
+      pagingInfo = PagingInfo(pageSize: 1, cursor: index, direction: PagingDirection.BACKWARD)
+      pb = pagingInfo.encode()
+      decodedPagingInfo = PagingInfo.init(pb.buffer)
+
+    check:
+      # the fields of decodedPagingInfo must be the same as the original pagingInfo
+      decodedPagingInfo.isErr == false
+      decodedPagingInfo.value == pagingInfo
+    
+    let
+      emptyPagingInfo = PagingInfo()
+      epb = emptyPagingInfo.encode()
+      decodedEmptyPagingInfo = PagingInfo.init(epb.buffer)
+
+    check:
+      # check the correctness of init and encode for an empty PagingInfo
+      decodedEmptyPagingInfo.isErr == false
+      decodedEmptyPagingInfo.value == emptyPagingInfo
+  
+  test "HistoryQuery Protobuf encod/init test":
+    let
+      index = computeIndex(WakuMessage(payload: @[byte 1], contentTopic: ContentTopic(1)))
+      pagingInfo = PagingInfo(pageSize: 1, cursor: index, direction: PagingDirection.BACKWARD)
+      query=HistoryQuery(topics: @[ContentTopic(1)], pagingInfo: pagingInfo)
+      pb = query.encode()
+      decodedQuery = HistoryQuery.init(pb.buffer)
+
+    check:
+      # the fields of decoded query decodedQuery must be the same as the original query query
+      decodedQuery.isErr == false
+      decodedQuery.value == query
+    
+    let 
+      emptyQuery=HistoryQuery()
+      epb = emptyQuery.encode()
+      decodedEmptyQuery = HistoryQuery.init(epb.buffer)
+
+    check:
+      # check the correctness of init and encode for an empty HistoryQuery
+      decodedEmptyQuery.isErr == false
+      decodedEmptyQuery.value == emptyQuery
+  
+  test "HistoryResponse Protobuf encod/init test":
+    let
+      wm = WakuMessage(payload: @[byte 1], contentTopic: ContentTopic(1))
+      index = computeIndex(wm)
+      pagingInfo = PagingInfo(pageSize: 1, cursor: index, direction: PagingDirection.BACKWARD)
+      res = HistoryResponse(messages: @[wm], pagingInfo:pagingInfo)
+      pb = res.encode()
+      decodedRes = HistoryResponse.init(pb.buffer)
+
+    check:
+      # the fields of decoded response decodedRes must be the same as the original response res
+      decodedRes.isErr == false
+      decodedRes.value == res
+    
+    let 
+      emptyRes=HistoryResponse()
+      epb = emptyRes.encode()
+      decodedEmptyRes = HistoryResponse.init(epb.buffer)
+
+    check:
+      # check the correctness of init and encode for an empty HistoryResponse
+      decodedEmptyRes.isErr == false
+      decodedEmptyRes.value == emptyRes
+    

waku/node/v2/waku_types.nim

@@ -25,7 +25,8 @@ type
     payload*: seq[byte]
     contentTopic*: ContentTopic
 
-  MessageNotificationHandler* = proc(topic: string, msg: WakuMessage): Future[void] {.gcsafe, closure.}
+  MessageNotificationHandler* = proc(topic: string, msg: WakuMessage): Future[
+      void] {.gcsafe, closure.}
 
   MessageNotificationSubscriptions* = TableRef[string, MessageNotificationSubscription]
 
@@ -35,20 +36,27 @@ type
 
   QueryHandlerFunc* = proc(response: HistoryResponse) {.gcsafe, closure.}
 
+
   Index* = object
-    ## This type contains the  description of an index used in the pagination of waku messages
+    ## This type contains the  description of an Index used in the pagination of WakuMessages
     digest*: MDigest[256]
-    receivedTime*: float
+    receivedTime*: float64
 
   IndexedWakuMessage* = object
+    ## This type is used to encapsulate a WakuMessage and its Index
     msg*: WakuMessage
     index*: Index
 
+  PagingDirection* {.pure.} = enum
+    ## PagingDirection determines the direction of pagination
+    BACKWARD = uint32(0)
+    FORWARD = uint32(1)
+
   PagingInfo* = object
     ## This type holds the information needed for the pagination
-    pageSize*: int
+    pageSize*: uint64
     cursor*: Index
-    direction*: bool
+    direction*: PagingDirection
 
   HistoryQuery* = object
     topics*: seq[ContentTopic]
@@ -182,7 +190,7 @@ proc computeIndex*(msg: WakuMessage): Index =
   if msg.contentTopic != 0: # checks for non-empty contentTopic
     ctx.update(msg.contentTopic.toBytes()) # converts the topic to bytes
   ctx.update(msg.payload)
-  let digest = ctx.finish()  # computes the hash
+  let digest = ctx.finish() # computes the hash
   ctx.clear()
 
   result.digest = digest

waku/protocol/v2/waku_store.nim

@@ -16,6 +16,90 @@ logScope:
 const
   WakuStoreCodec* = "/vac/waku/store/2.0.0-beta1"
 
+
+proc encode*(index: Index): ProtoBuffer =
+  ## encodes an Index object into a ProtoBuffer
+  ## returns the resultant ProtoBuffer
+
+  # intiate a ProtoBuffer
+  result = initProtoBuffer()
+
+  # encodes index
+  result.write(1, index.digest.data)
+  result.write(2, index.receivedTime)
+
+proc encode*(pd: PagingDirection): ProtoBuffer =
+  ## encodes a PagingDirection into a ProtoBuffer
+  ## returns the resultant ProtoBuffer
+
+  # intiate a ProtoBuffer
+  result = initProtoBuffer()
+
+  # encodes pd
+  result.write(1, uint32(ord(pd)))
+
+proc encode*(pinfo: PagingInfo): ProtoBuffer =
+  ## encodes a PagingInfo object into a ProtoBuffer
+  ## returns the resultant ProtoBuffer
+
+  # intiate a ProtoBuffer
+  result = initProtoBuffer()
+
+  # encodes pinfo
+  result.write(1, pinfo.pageSize)
+  result.write(2, pinfo.cursor.encode())
+  result.write(3, pinfo.direction.encode())
+
+proc init*(T: type Index, buffer: seq[byte]): ProtoResult[T] =
+  ## creates and returns an Index object out of buffer
+  var index = Index()
+  let pb = initProtoBuffer(buffer)
+
+  var data: seq[byte]
+  discard ? pb.getField(1, data)
+
+  # create digest from data
+  index.digest = MDigest[256]()
+  for count, b in data:
+    index.digest.data[count] = b
+
+  # read the receivedTime
+  var receivedTime: float64
+  discard ? pb.getField(2, receivedTime)
+  index.receivedTime = receivedTime
+
+  ok(index) 
+
+proc init*(T: type PagingDirection, buffer: seq[byte]): ProtoResult[T] =
+  ## creates and returns a PagingDirection object out of buffer
+  let pb = initProtoBuffer(buffer)
+
+  var dir: uint32
+  discard ? pb.getField(1, dir)
+  var direction = PagingDirection(dir)
+
+  ok(direction)
+
+proc init*(T: type PagingInfo, buffer: seq[byte]): ProtoResult[T] =
+  ## creates and returns a PagingInfo object out of buffer
+  var pagingInfo = PagingInfo()
+  let pb = initProtoBuffer(buffer)
+
+  var pageSize: uint32
+  discard ? pb.getField(1, pageSize)
+  pagingInfo.pageSize = pageSize
+
+
+  var cursorBuffer: seq[byte]
+  discard ? pb.getField(2, cursorBuffer)
+  pagingInfo.cursor = ? Index.init(cursorBuffer)
+
+  var directionBuffer: seq[byte]
+  discard ? pb.getField(3, directionBuffer)
+  pagingInfo.direction = ? PagingDirection.init(directionBuffer)
+
+  ok(pagingInfo) 
+  
 proc init*(T: type HistoryQuery, buffer: seq[byte]): ProtoResult[T] =
   var msg = HistoryQuery()
   let pb = initProtoBuffer(buffer)
@@ -25,6 +109,12 @@ proc init*(T: type HistoryQuery, buffer: seq[byte]): ProtoResult[T] =
   discard ? pb.getRepeatedField(1, topics)
 
   msg.topics = topics
+
+  var pagingInfoBuffer: seq[byte]
+  discard ? pb.getField(2, pagingInfoBuffer)
+
+  msg.pagingInfo = ? PagingInfo.init(pagingInfoBuffer)
+
   ok(msg)
 
 proc init*(T: type HistoryResponse, buffer: seq[byte]): ProtoResult[T] =
@@ -35,7 +125,11 @@ proc init*(T: type HistoryResponse, buffer: seq[byte]): ProtoResult[T] =
   discard ? pb.getRepeatedField(1, messages)
 
   for buf in messages:
-    msg.messages.add(? WakuMessage.init(buf))
+    msg.messages.add( ? WakuMessage.init(buf))
+
+  var pagingInfoBuffer: seq[byte]
+  discard ? pb.getField(2,pagingInfoBuffer)
+  msg.pagingInfo= ? PagingInfo.init(pagingInfoBuffer)
 
   ok(msg)
 
@@ -62,6 +156,8 @@ proc encode*(query: HistoryQuery): ProtoBuffer =
 
   for topic in query.topics:
     result.write(1, topic)
+  
+  result.write(2, query.pagingInfo.encode())
 
 proc encode*(response: HistoryResponse): ProtoBuffer =
   result = initProtoBuffer()
@@ -69,6 +165,8 @@ proc encode*(response: HistoryResponse): ProtoBuffer =
   for msg in response.messages:
     result.write(1, msg.encode())
 
+  result.write(2, response.pagingInfo.encode())
+
 proc encode*(rpc: HistoryRPC): ProtoBuffer =
   result = initProtoBuffer()