Merge pull request #5 from aj-ptw/master

Fix packet parsing issues

Author: AJ Keller

.travis.yml

@@ -7,4 +7,5 @@ node_js:
 install:
   - npm install --all
 script:
+  - npm run test-lint
   - npm run test-cov

changelog.md

@@ -1,3 +1,24 @@
+# 0.0.8
+
+### New Features
+
+* Sample object now has property `valid` of type `boolean`, `false` when error parseing packet, `true` otherwise. On `false` there will be another property called `error` of type `string` which contains an error message.
+
+# 0.0.7
+
+### Continuous Integration
+
+* Add `npm run test-lint` to add linting to travis.yml
+
+### Bug Fixes
+
+* Last sample number was confusing to use with `transformRawDataPacketsToSample`
+
+### New Features
+
+* In openBCIUtilities.js add function `transformRawDataPacketToSample` to parse a single raw data packet
+* In openBCIConstants.js add function `rawDataToSampleObjectDefault(numChannels)` which should be used by drivers to create the object that is passed through each call to `transformRawDataPacketsToSample` 
+
 # 0.0.6
 
 ### Bug Fixes

openBCIConstants.js

@@ -486,11 +486,11 @@ const obciNobleEmitterStateChange = 'stateChange';
 const obciNobleStatePoweredOn = 'poweredOn';
 
 /** Protocols */
-const obciProtocolBLE = "ble";
-const obciProtocolSerial = "serial";
-const obciProtocolWifi = "wifi";
+const obciProtocolBLE = 'ble';
+const obciProtocolSerial = 'serial';
+const obciProtocolWifi = 'wifi';
 
-module.exports = {
+const constantsModule = {
   /** Turning channels off */
   OBCIChannelOff1: obciChannelOff1,
   OBCIChannelOff2: obciChannelOff2,
@@ -1178,11 +1178,13 @@ module.exports = {
   commandSampleRateForCmdCyton,
   commandSampleRateForCmdGanglion,
   commandBoardModeForMode,
+  rawDataToSampleObjectDefault,
   /** Protocols */
   OBCIProtocolBLE: obciProtocolBLE,
   OBCIProtocolSerial: obciProtocolSerial,
   OBCIProtocolWifi: obciProtocolWifi
 };
+module.exports = constantsModule;
 
 /**
 * @description To add a usability abstraction layer above channel setting commands. Due to the
@@ -1528,6 +1530,25 @@ function channelSettingsObjectDefault (channelNumber) {
   };
 }
 
+/**
+ * @description RawDataToSample default object creation
+ * @param numChannels {Number} - The number of channels
+ * @returns {RawDataToSample} - A new object
+ */
+function rawDataToSampleObjectDefault (numChannels) {
+  if (_.isUndefined(numChannels)) numChannels = obciNumberOfChannelsDefault;
+  return {
+    accelArray: [0, 0, 0],
+    channelSettings: constantsModule.channelSettingsArrayInit(numChannels),
+    lastSampleNumber: 0,
+    rawDataPacket: Buffer.alloc(33),
+    rawDataPackets: [],
+    scale: true,
+    timeOffset: 0,
+    verbose: false
+  };
+}
+
 /**
  * Get's the command for sample rate Cyton
  * @param sampleRate {Number} - The desired sample rate

openBCIUtilities.js

@@ -28,6 +28,17 @@ var utilitiesModule = {
    * @property {Array} channelData The extracted channel data
    * @property {Buffer} rawDataPacket The raw data packet
    */
+  /**
+   * @typedef {Object} RawDataToSample
+   * @property {Array} rawDataPackets - An array of rawDataPackets
+   * @property {Buffer} rawDataPacket - A single raw data packet
+   * @property {Array} channelSettings - The channel settings array
+   * @property {Number} timeOffset (optional) for non time stamp use cases i.e. 0xC0 or 0xC1 (default and raw aux)
+   * @property {Array} accelArray (optional) for non time stamp use cases
+   * @property {Boolean} verbose (optional) for verbose output
+   * @property {Number} lastSampleNumber (optional) - The last sample number
+   * @property {Boolean} scale (optional) Default `true`. A gain of 24 for Cyton will be used and 51 for ganglion by default.
+   */
   /**
    * @description Used to extract samples out of a buffer of unknown length
    * @param dataBuffer {Buffer} - A buffer to parse for samples
@@ -107,6 +118,7 @@ var utilitiesModule = {
     };
   },
 
+  transformRawDataPacketToSample,
   transformRawDataPacketsToSample,
   getRawPacketType,
   getFromTimePacketAccel,
@@ -879,71 +891,71 @@ function newSyncObject () {
 
 /**
  * @description Used transform raw data packets into fully qualified packets
- * @param o {Object}
- * @param o.rawDataPackets {Array} - An array of rawDataPackets
- * @param o.channelSettings {Array}
- * @param o.timeOffset {Number} (optional) for non time stamp use cases i.e. 0xC0 or 0xC1 (default and raw aux)
- * @param o.accelArray {Array} (optional) for non time stamp use cases
- * @param o.verbose {Boolean} (optional) for verbose output
- * @param o.scale {Boolean} (optional) Default `true`. A gain of 24 for Cyton will be used and 51 for ganglion by default.
+ * @param o {RawDataToSample} - Used to hold data and configuration settings
  * @return {Array} samples An array of {Sample}
  * @author AJ Keller (@pushtheworldllc)
  */
 function transformRawDataPacketsToSample (o) {
   let samples = [];
   for (let i = 0; i < o.rawDataPackets.length; i++) {
-    const rawDataPacket = o.rawDataPackets[i];
-    const packetType = getRawPacketType(rawDataPacket[k.OBCIPacketPositionStopByte]);
-    let sample;
-    try {
-      switch (packetType) {
-        case k.OBCIStreamPacketStandardAccel:
-          sample = utilitiesModule.parsePacketStandardAccel({
-            rawDataPacket,
-            channelSettings: o.channelSettings,
-            scale: o.scale
-          });
-          break;
-        case k.OBCIStreamPacketStandardRawAux:
-          sample = utilitiesModule.parsePacketStandardRawAux({
-            rawDataPacket,
-            channelSettings: o.channelSettings,
-            scale: o.scale
-          });
-          break;
-        case k.OBCIStreamPacketAccelTimeSyncSet:
-        case k.OBCIStreamPacketAccelTimeSynced:
-          sample = utilitiesModule.parsePacketTimeSyncedAccel({
-            rawDataPacket,
-            channelSettings: o.channelSettings,
-            timeOffset: o.timeOffset,
-            accelArray: o.accelArray
-          });
-          break;
-        case k.OBCIStreamPacketRawAuxTimeSyncSet:
-        case k.OBCIStreamPacketRawAuxTimeSynced:
-          sample = utilitiesModule.parsePacketTimeSyncedRawAux({
-            rawDataPacket,
-            channelSettings: o.channelSettings,
-            timeOffset: o.timeOffset
-          });
-          break;
-        default:
-          // Don't do anything if the packet is not defined
-          break;
-      }
-      samples.push(sample);
-    } catch (err) {
-      samples.push({
-        rawDataPacket
-      });
-      if (o.verbose) console.log(err);
+    o.rawDataPacket = o.rawDataPackets[i];
+    const sample = transformRawDataPacketToSample(o);
+    samples.push(sample);
+    if (sample.hasOwnProperty('sampleNumber')) {
+      o['lastSampleNumber'] = sample.sampleNumber;
+    } else {
+      o['lastSampleNumber'] = o.rawDataPacket[k.OBCIPacketPositionSampleNumber];
     }
   }
-
   return samples;
 }
 
+/**
+ * @description Used transform raw data packets into fully qualified packets
+ * @param o {RawDataToSample} - Used to hold data and configuration settings
+ * @return {Array} samples An array of {Sample}
+ * @author AJ Keller (@pushtheworldllc)
+ */
+function transformRawDataPacketToSample (o) {
+  let sample;
+  try {
+    const packetType = getRawPacketType(o.rawDataPacket[k.OBCIPacketPositionStopByte]);
+    switch (packetType) {
+      case k.OBCIStreamPacketStandardAccel:
+        sample = utilitiesModule.parsePacketStandardAccel(o);
+        break;
+      case k.OBCIStreamPacketStandardRawAux:
+        sample = utilitiesModule.parsePacketStandardRawAux(o);
+        break;
+      case k.OBCIStreamPacketAccelTimeSyncSet:
+      case k.OBCIStreamPacketAccelTimeSynced:
+        sample = utilitiesModule.parsePacketTimeSyncedAccel(o);
+        break;
+      case k.OBCIStreamPacketRawAuxTimeSyncSet:
+      case k.OBCIStreamPacketRawAuxTimeSynced:
+        sample = utilitiesModule.parsePacketTimeSyncedRawAux(o);
+        break;
+      default:
+        // Don't do anything if the packet is not defined
+        sample = {
+          error: `bad stop byte ${o.rawDataPacket.slice(32, 33).toString('hex')}`,
+          valid: false,
+          rawDataPacket: o.rawDataPacket
+        };
+        if (o.verbose) console.log(sample.error);
+        break;
+    }
+  } catch (err) {
+    sample = {
+      error: err,
+      valid: false,
+      rawDataPacket: o.rawDataPacket
+    };
+    if (o.verbose) console.log(err);
+  }
+  return sample;
+}
+
 /**
  * @description This method parses a 33 byte OpenBCI V3 packet and converts to a sample object
  * @param o {Object} - The input object
@@ -952,6 +964,7 @@ function transformRawDataPacketsToSample (o) {
  *                  calling k.channelSettingsArrayInit(). The most important rule here is that it is
  *                  Array of objects that have key-value pair {gain:NUMBER}
  * @param o.scale {Boolean} - Do you want to scale the results? Default true
+ * @param o.lastSampleNumber {Number} - The last sample number
  * @returns {Sample} - A sample object. NOTE: Only has accelData if this is a Z axis packet.
  */
 function parsePacketStandardAccel (o) {
@@ -982,6 +995,8 @@ function parsePacketStandardAccel (o) {
   // Get the stop byte
   sampleObject.stopByte = o.rawDataPacket[k.OBCIPacketPositionStopByte];
 
+  sampleObject.valid = true;
+
   return sampleObject;
 }
 
@@ -993,6 +1008,7 @@ function parsePacketStandardAccel (o) {
  *                  calling k.channelSettingsArrayInit(). The most important rule here is that it is
  *                  Array of objects that have key-value pair {gain:NUMBER}
  * @param o.scale {Boolean} - Do you want to scale the results? Default is true
+ * @param o.lastSampleNumber {Number} - The last sample number
  * @returns {Sample} - A sample object. NOTE: Only has accelData if this is a Z axis packet.
  */
 function parsePacketStandardRawAux (o) {
@@ -1024,6 +1040,8 @@ function parsePacketStandardRawAux (o) {
   // Get the stop byte
   sampleObject.stopByte = o.rawDataPacket[k.OBCIPacketPositionStopByte];
 
+  sampleObject.valid = true;
+
   return sampleObject;
 }
 
@@ -1078,6 +1096,8 @@ function parsePacketTimeSyncedAccel (o) {
   if (o.scale) sampleObject.channelData = getChannelDataArray(o);
   else sampleObject.channelDataCounts = getChannelDataArrayNoScale(o.rawDataPacket);
 
+  sampleObject.valid = true;
+
   return sampleObject;
 }
 
@@ -1125,6 +1145,8 @@ function parsePacketTimeSyncedRawAux (o) {
   if (o.scale) sampleObject.channelData = getChannelDataArray(o);
   else sampleObject.channelDataCounts = getChannelDataArrayNoScale(o.rawDataPacket);
 
+  sampleObject.valid = true;
+
   return sampleObject;
 }
 

package.json

@@ -1,10 +1,11 @@
 {
   "name": "openbci-utilities",
-  "version": "0.0.6",
+  "version": "0.0.8",
   "description": "The official utility package of Node.js SDK for the OpenBCI Biosensor Boards.",
   "main": "index.js",
   "scripts": {
-    "test": "semistandard | snazzy && mocha test",
+    "test": "mocha test",
+    "test-lint": "semistandard | snazzy",
     "test-cov": "istanbul cover ./node_modules/mocha/bin/_mocha -- -R spec && codecov"
   },
   "keywords": [

test/openBCIConstants-test.js

@@ -969,16 +969,16 @@ describe('OpenBCIConstants', function () {
   });
   describe('Board Types', function () {
     it('should get right name for chan daisy', function () {
-      expect(k.OBCIBoardDaisy).to.equal("daisy");
+      expect(k.OBCIBoardDaisy).to.equal('daisy');
     });
     it('should get right name for chan cyton', function () {
-      expect(k.OBCIBoardCyton).to.equal("cyton");
+      expect(k.OBCIBoardCyton).to.equal('cyton');
     });
     it('should get right name for chan ganglion', function () {
-      expect(k.OBCIBoardGanglion).to.equal("ganglion");
+      expect(k.OBCIBoardGanglion).to.equal('ganglion');
     });
     it('should get right name for chan none', function () {
-      expect(k.OBCIBoardNone).to.equal("none");
+      expect(k.OBCIBoardNone).to.equal('none');
     });
   });
   describe('numberOfChannelsForBoardTypes', function () {