Implementing Kafka datapath for data packages utilizing Avro

gateway.go

@@ -1,11 +1,15 @@
 package main
 
 import (
+	"Gateway-Server/model"
+	"bytes"
+	"context"
 	"database/sql"
 	"encoding/json"
 	"fmt"
 	_ "github.com/go-sql-driver/mysql"
 	"github.com/gorilla/websocket"
+	"github.com/segmentio/kafka-go"
 	"io/ioutil"
 	"net/http"
 	"os"
@@ -117,8 +121,63 @@ func (ws *socketConn) handleData(data Packet) {
 		fmt.Printf("Error unmarshalling data: %v\n", err)
 	} else {
 		fmt.Printf("got some data: %v\n", msg)
-		// TODO: Better response handling
 		ws.lock.Lock()
+		var dataPackage = avro.NewDataPackage()
+		dataPackage.Generator = int32(genMap.mapping[ws.genId].databaseId)
+		// TODO: Have to get the generators state and region, probably in the same generator id map structure
+		dataPackage.State = avro.State(avro.StateCT)
+		dataPackage.Region = avro.Region(avro.RegionNORTHEAST)
+		for metric, stampedReadings := range msg {
+			var metricData = avro.NewMetricData()
+			metricData.Metric = metric
+			for _, reading := range stampedReadings {
+				var dataPoint = avro.NewDataPoint()
+				dataPoint.Timestamp = int64(reading.Timestamp)
+				var val = avro.UnionLongDouble{}
+				switch v := (reading.Value).(type) {
+				case int:
+				case int8:
+				case int16:
+				case int32:
+				case int64:
+					val.Long = int64(v)
+					val.UnionType = avro.UnionLongDoubleTypeEnumLong
+					break
+				case float32:
+				case float64:
+					val.Double = float64(v)
+					val.UnionType = avro.UnionLongDoubleTypeEnumDouble
+					break
+				}
+				dataPoint.Value = val
+				metricData.Datapoints = append(metricData.Datapoints, dataPoint)
+			}
+			dataPackage.Data = append(dataPackage.Data, metricData)
+		}
+		out := new(bytes.Buffer)
+		if err := dataPackage.Serialize(out); err != nil {
+			fmt.Printf("Error serializing data: %v\n", err)
+		}
+
+		w := kafka.NewWriter(kafka.WriterConfig{
+			Brokers: []string{"sd5-data.engr.uconn.edu:9092"},
+			Topic:   "GeneratorData",
+			Balancer: &kafka.LeastBytes{},
+		})
+
+		if err := w.WriteMessages(context.Background(),
+			kafka.Message{
+				Key:   []byte("DataPackage"),
+				Value: out.Bytes(),
+			},
+		); err != nil {
+			fmt.Printf("Error writing to Kafka: %v\v", err)
+		}
+
+		if err := w.Close(); err != nil {
+			fmt.Printf("Error closing kafka? Weird: %v\n", err)
+		}
+
 		if err := ws.conn.WriteJSON(Packet{data.ID, "response", []byte("received")}); err != nil {
 			fmt.Printf("Error sending response: %v\n", err)
 		} else {

model/datapackage.avsc

@@ -0,0 +1,64 @@
+{
+    "namespace": "com.powerpanel.kso.model",
+    "type": "record",
+    "name": "DataPackage",
+    "fields": [
+        {
+            "type": "int",
+            "name": "generator"
+        },
+        {
+            "name": "region",
+            "type": {
+                "name": "Region",
+                "type": "enum",
+                "symbols": ["NORTHEAST", "SOUTHEAST", "WEST", "MIDWEST"]
+            }
+        },
+        {
+            "name": "state",
+            "type": {
+                "name": "State",
+                "type": "enum",
+                "symbols": ["AL", "AK", "AZ", "AR", "CA", "CO", "CT", "DE", "FL", "GA", "HI", "ID", "IL", "IN", "IA", "KS", "KY", "LA", "ME", "MD", "MA", "MI", "MN", "MS", "MO", "MT", "NE", "NV", "NH", "NJ", "NM", "NY", "NC", "ND", "OH", "OK", "OR", "PA", "RI", "SC", "SD", "TN", "TX", "UT", "VT", "VA", "WA", "WV", "WI", "WY"]
+            }
+        },
+        {
+            "name": "data",
+            "type": {
+                "type": "array",
+                "items": {
+                    "name": "MetricData",
+                    "type": "record",
+                    "fields": [
+                        {
+                            "name": "metric",
+                            "type": "string"
+                        },
+                        {
+                            "name": "datapoints",
+                            "type": {
+                                "type": "array",
+                                "items": {
+                                    "name": "DataPoint",
+                                    "type": "record",
+                                    "fields": [
+                                        {
+                                            "name": "timestamp",
+                                            "type": "long"
+                                        },
+                                        {
+                                            "name": "value",
+                                            "type": ["long", "double"]
+                                        }
+                                    ]
+                                }
+
+                            }
+                        }
+                    ]
+                }
+            }
+        }
+    ]
+}