coap - npm Package Compare versions

Comparing version 0.6.1 to 0.7.0

lib/agent.js

@@ -22,2 +22,5 @@ /*
     , RetrySend       = require('./retry_send')
+    , parseBlock2     = require('./helpers').parseBlock2
+    , createBlock2    = require('./helpers').createBlock2
+    , getOption       = require('./helpers').getOption
     , maxToken        = Math.pow(2, 32)
@@ -163,6 +166,54 @@ , maxMessageId    = Math.pow(2, 16)
 
-  if (req.response)
+  var block2Buff = getOption(packet.options, 'Block2')
+  var block2
+  // if we got blockwise (2) response
+  if (block2Buff) {
+    block2 = parseBlock2(block2Buff)
+    // check for error
+    if (!block2) {
+      req.sender.reset()
+      return req.emit('error', err)
+    }
+  }
+  if (block2) {
+    // accumulate payload
+    req._totalPayload = Buffer.concat([req._totalPayload, packet.payload])
+
+    if (block2.moreBlock2) {
+      // increase message id for next request
+      delete this._msgIdToReq[req._packet.messageId]
+      req._packet.messageId = that._nextMessageId()
+      this._msgIdToReq[req._packet.messageId] = req 
+
+      // next block2 request
+      var block2Val = createBlock2({
+        moreBlock2: false,
+        num: block2.num+1,
+        size: block2.size
+      })
+      if (!block2Val) {
+        req.sender.reset()
+        return req.emit('error', err)
+      }
+      req.setOption('Block2', block2Val)
+      req.sender.send(generate(req._packet))
+
+      return
+    }
+    else {
+      // get full payload
+      packet.payload = req._totalPayload
+      // clear the payload incase of block2
+      req._totalPayload = new Buffer(0)
+    }
+  }
+
+  if (req.response) {
     // it is an observe request
     // and we are already streaming
     return req.response.append(packet)
+  }
+  else if (block2) {
+    delete that._tkToReq[req._packet.token.readUInt32BE(0)]
+  }
   else if (!req.url.observe)
@@ -178,4 +229,5 @@ // it is not, so delete the token
     })
-  } else
+  } else {
     response = new IncomingMessage(packet, rsinfo)
+  }
 
@@ -264,2 +316,4 @@ req.response = response
 
+  req._totalPayload = new Buffer(0) 
+
   return req
@@ -266,0 +320,0 @@ }

lib/helpers.js

@@ -118,1 +118,84 @@ /*
 }
+
+/*
+get an option value from options
+  options     array of object, in form {name: , value}
+  name        name of the object wanted to retrive
+  return      value, or null
+*/
+module.exports.getOption = function getOption(options, name) {
+  for (var i in options)
+    if (options[i].name == name)
+      return options[i].value
+  return null
+}
+/*
+parse block2
+  value       block2 value buffer
+  return      object describes block2, {moreBlock2: , num: , size: }
+
+with invalid block2 value, the function return null
+*/
+module.exports.parseBlock2 = function parseBlock2(block2Value) {
+  var num
+  switch (block2Value.length) {
+    case 1:
+    num = block2Value[0] >> 4
+    break
+    case 2:
+    num = (block2Value[0]*256 + block2Value[1]) >> 4
+    break
+    case 3:
+    num = (block2Value[0]*256*256 + block2Value[1]*256 + block2Value[2]) >>4
+    break
+    default:
+    // Block2 is more than 3 bytes
+    return null
+  }
+  // limit value of size is 1024 (2**(6+4))
+  if (block2Value.slice(-1)[0] == 7) {
+    // Block size is bigger than 1024
+    return null
+  }
+  return {
+    moreBlock2: (block2Value.slice(-1)[0] & (0x01<<3))? true:false,
+    num: num,
+    size: Math.pow(2, (block2Value.slice(-1)[0] & 0x07)+4)
+  }
+}
+
+/*
+create buffer for block2 option
+  requestedBlock      object contain block2 infor, e.g. {moreBlock2: true, num: 100, size: 32}
+  return              new Buffer, carry block2 value
+*/
+module.exports.createBlock2 = function createBlock2(requestedBlock) {
+  var byte
+  var szx = Math.log(requestedBlock.size)/Math.log(2) - 4
+  var m = ((requestedBlock.moreBlock2==true)?0:1)
+  var num = requestedBlock.num
+  var extraNum
+
+  byte = 0
+  byte |= szx
+  byte |= m << 3
+  byte |= (num&0xf) <<4
+
+  // total num occupy up to 5 octets
+  // num share the higher octet of first byte, and (may) take more 2 bytes for the rest 4 octets
+  if (num <= 0xf) { 
+    extraNum = null
+  }
+  else if (num <=0xfff) {
+    extraNum = new Buffer([num/16])
+  } 
+  else if (num <=0xfffff) {
+    extraNum = new Buffer(2)
+    extraNum.writeUInt16BE(num>>4,0)
+  } 
+  else {
+    // too big block2 number
+    return null
+  }
+  return (extraNum)? Buffer.concat([extraNum, new Buffer([byte])]):new Buffer([byte])
+}

lib/parameters.js

@@ -50,2 +50,5 @@ /*
 
+// default max packet size
+p.maxPacketSize = 1280
+
 module.exports = p

lib/server.js

@@ -20,2 +20,5 @@ /*
     , RetrySend       = require('./retry_send')
+    , parseBlock2     = require('./helpers').parseBlock2
+    , createBlock2    = require('./helpers').createBlock2
+    , getOption       = require('./helpers').getOption
 
@@ -66,2 +69,4 @@ function CoAPServer(options, listener) {
 
+
+
   if (listener)
@@ -117,3 +122,3 @@ this.on('request', listener)
     , cached    = lru.peek(toKey(rsinfo.address, rsinfo.port, packet, true))
-    , Message   = OutgoingMessage
+    , Message   = OutMessage 
     , that = this
@@ -153,3 +158,3 @@ , request
 
-    if (Message === OutgoingMessage) {
+    if (Message === OutMessage) {
       sender.on('error', response.emit.bind(response, 'error'))
@@ -174,2 +179,13 @@ } else {
 
+  // if (response instanceof OutMessage) {
+    response._request = request._packet
+  // }
+
+  // todo:
+  // should use mem cache to buffer responses
+  // dont alway bother uper layer, especially when the return is in blockwise (2)
+  // if (cachedPayload)
+  //   response.end(cachedPayload);
+  // else
+  //   this.emit('request', request, response)
   this.emit('request', request, response)
@@ -187,2 +203,96 @@ }
 
+/*
+new out message
+inherit from OutgoingMessage
+to handle cached answer and blockwise (2)
+*/
+function OutMessage() {
+  OutgoingMessage.apply(this, Array.prototype.slice.call(arguments));
+}
+util.inherits(OutMessage, OutgoingMessage)
+
+// maxBlock2 is in formular 2**(i+4), and must <= 2**(6+4)
+var maxBlock2 = Math.pow(2, Math.floor(Math.log(parameters.maxPacketSize)/Math.log(2)))
+if (maxBlock2 > Math.pow(2, (6+4)))
+  maxBlock2 = Math.pow(2, (6+4))
+
+OutMessage.prototype.end= function(payload) {
+  var that = this
+
+  var block2Buff = getOption(this._request.options, 'Block2')
+  var requestedBlockOption
+  // if we got blockwise (2) resquest
+  if (block2Buff) {
+    requestedBlockOption = parseBlock2(block2Buff)
+    // bad option
+    if (!requestedBlockOption) {
+      that.statusCode = '4.02'
+      return OutgoingMessage.prototype.end.call(that)
+    }
+  }
+
+  // if payload is suitable for ONE message, shoot it out
+  if (!payload || 
+    ((!requestedBlockOption) && (payload.length < parameters.maxPacketSize)))
+    return OutgoingMessage.prototype.end.call(this, payload)
+
+  // for the first request, block2 option may be missed
+  if (!requestedBlockOption) 
+    requestedBlockOption = {
+      size: maxBlock2,
+      num: 0
+    }
+
+  // block2 size should not bigger than maxBlock2
+  if (requestedBlockOption.size > maxBlock2) 
+    requestedBlockOption.size = maxBlock2
+
+  // block number should have limit 
+  // 0 base counter for totalBlock, hence use floor (vs ceil)
+  var totalBlock = Math.floor(payload.length/requestedBlockOption.size)
+  var isLastBlock
+  if (requestedBlockOption.num < totalBlock)
+    isLastBlock = false
+  else if (requestedBlockOption.num == totalBlock) 
+    isLastBlock = true
+  else {
+    // precondition fail, may request for out of range block
+    that.statusCode = '4.02'
+    return OutgoingMessage.prototype.end.call(that)
+  }
+
+  var block2 = createBlock2({
+    moreBlock2: isLastBlock,
+    num: requestedBlockOption.num,
+    size: requestedBlockOption.size
+  })
+  if (!block2) {
+    // this catch never be match,
+    // since we're gentleman, just handle it 
+    that.statusCode = '4.02'
+    return OutgoingMessage.prototype.end.call(that)
+  }
+  this.setOption('Block2', block2)
+  this.setOption('ETag', _toETag(payload))
+
+  OutgoingMessage.prototype.end.call(this, payload.slice((requestedBlockOption.num)*requestedBlockOption.size, (requestedBlockOption.num+1)*requestedBlockOption.size))
+};
+
+/*
+calculate id of a payload by xor each 2-byte-block from it
+use to generate etag
+  payload         an input buffer, represent payload need to generate id (hash)
+  id              return var, is a buffer(2)
+*/
+function _toETag(payload) {
+  var id = new Buffer([0,0])
+  var i = 0
+  do {
+    id[0] ^= payload[i]
+    id[1] ^= payload[i+1]
+    i += 2
+  } while (i<payload.length)
+  return id
+}
+
 module.exports = CoAPServer

package.json

 {
   "name": "coap",
-  "version": "0.6.1",
+  "version": "0.7.0",
   "description": "A CoAP library for node modelled after 'http'",
@@ -37,6 +37,6 @@ "main": "index.js",
   "dependencies": {
+    "bl": "~0.7.0",
     "coap-packet": "~0.1.8",
-    "bl": "~0.7.0",
     "lru-cache": "~2.5.0"
   }
 }

README.md

@@ -28,7 +28,8 @@ node-coap
 
-This library follows the
-[draft-18](http://tools.ietf.org/html/draft-ietf-core-coap-18) of the standard.
-Moreover, it supports the
-[observe-11](http://tools.ietf.org/html/draft-ietf-core-observe-11)
-specification.
+This library follows:
+* [draft-18](http://tools.ietf.org/html/draft-ietf-core-coap-18) of CoAP.
+* [observe-11](http://tools.ietf.org/html/draft-ietf-core-observe-11)
+  for the observe specification.
+* [block-14](http://tools.ietf.org/id/draft-ietf-core-block-14.txt) for
+  the blockwise specification.
 
@@ -262,4 +263,8 @@ It does not parse the protocol but it use
 Also, `'Content-Type'` is aliased to `'Content-Format'` for HTTP
-compatibility.
+compatibility.gg
 
+Since v0.7.0, this library supports blockwise transfers, you can trigger
+them by adding a `req.setOption('Block2', new Buffer([0x2]))` to the
+output of [request](#request).
+
 See the
@@ -449,2 +454,3 @@ [spec](http://tools.ietf.org/html/draft-ietf-core-coap-18#section-5.4)
 <tr><th align="left">Matteo Collina</th><td><a href="https://github.com/mcollina">GitHub/mcollina</a></td><td><a href="https://twitter.com/matteocollina">Twitter/@matteocollina</a></td></tr>
+<tr><th align="left">Nguyen Quoc Dinh</th><td><a href="https://github.com/nqd">GitHub/nqd</a></td><td><a href="https://twitter.com/nqdinh">Twitter/@nqdinh</a></td></tr>
 </tbody></table>
@@ -451,0 +457,0 @@

test/server.js

@@ -184,13 +184,2 @@
 
-  it('should have res emitting an error if the message is too big', function(done) {
-    send(generate())
-    server.on('request', function(req, res) {
-      res.on('error', function() {
-        done()
-      })
-
-      res.end(new Buffer(1280))
-    })
-  })
-
   it('should expose the options', function(done) {
@@ -197,0 +186,0 @@ var options = [{

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Improved metrics

Total package byte prevSize

119337

increased by11.18%

Number of package files

31

increased by6.9%

Lines of code

3260

increased by13.16%

Number of lines in readme file

461

increased by1.32%

No dependency changes