// Copyright (C) 2015-2017 Mikael Berthe <mikael@lilotux.net>. All rights reserved.
// Use of this source code is governed by the MIT license,
// which can be found in the LICENSE file.
//
// Thanks to atbrask's blog post <http://www.atbrask.dk/?p=98> for the
// protocol details.
// gobm65 is a Beurer BM65 Blood Pressure Monitor CLI reader.
package main
// Installation:
//
// % go get hg.lilotux.net/golang/mikael/gobm65
//
// Examples:
//
// Get help:
// % gobm65 --help
//
// Get records and display the average:
// % gobm65 --average
//
// Display the latest 3 records with the average:
// % gobm65 -l 3 --average
// Display all records since a specific date:
// % gobm65 --since "2016-06-01"
// Display all records of the last 7 days:
// % gobm65 --since "$(date "+%F" -d "7 days ago")"
//
// Display the last/first 10 records in JSON:
// % gobm65 -l 10 --format json
//
// Save the records to a JSON file:
// % gobm65 -o data_u2.json
//
// Read a JSON file and display average of the last 3 records:
// % gobm65 -i data_u2.json -l 3 --average
// Read a JSON file, merge with device records, and save to another file:
// % gobm65 -i data_u2.json --merge -o data_u2-new.json
import (
"encoding/json"
"fmt"
"io"
"io/ioutil"
"log"
"math"
"sort"
"time"
flag "github.com/docker/docker/pkg/mflag"
"github.com/tarm/serial"
)
type measurement struct {
Header int
Systolic int
Diastolic int
Pulse int
Month int
Day int
Hour int
Minute int
Year int
}
func getData(s io.ReadWriteCloser, buf []byte, size int) (int, error) {
t := 0
b := buf
for t < size {
n, err := s.Read(b[t:])
if err != nil {
log.Fatal(err) // XXX
return t, err
}
//log.Printf("(%d bytes) %q\n", n, b[t:t+1])
t = t + n
}
return t, nil
}
func fetchData(dev string) (items []measurement, err error) {
c := &serial.Config{Name: dev, Baud: 4800}
var s *serial.Port
s, err = serial.OpenPort(c)
if err != nil {
return items, err
}
// =================== Handshake =====================
q := []byte("\xaa")
//log.Printf("Query: %q\n", q)
log.Println("Starting handshake...")
n, err := s.Write(q)
if err != nil {
return items, err
}
buf := make([]byte, 128)
n, err = getData(s, buf, 1)
if err != nil {
return items, err
}
if n == 1 && buf[0] == '\x55' {
log.Println("Handshake successful.")
} else {
log.Printf("(%d bytes) %q\n", n, buf[:n])
s.Close()
return items, fmt.Errorf("handshake failed")
}
// =================== Desc =====================
q = []byte("\xa4")
//log.Printf("Query: %q\n", q)
log.Println("Requesting device description...")
n, err = s.Write(q)
if err != nil {
return items, err
}
n, err = getData(s, buf, 32)
log.Printf("DESC> %q\n", buf[:n])
// =================== Count =====================
q = []byte("\xa2")
//log.Printf("Query: %q\n", q)
log.Println("Requesting data counter...")
n, err = s.Write(q)
if err != nil {
return items, err
}
n, err = getData(s, buf, 1)
if err != nil {
return items, err
}
var nRecords int
if n == 1 {
log.Printf("%d item(s) available.", buf[0])
nRecords = int(buf[0])
} else {
log.Printf("(%d bytes) %q\n", n, buf[:n])
return items, fmt.Errorf("no measurement found")
}
// =================== Records =====================
for i := 0; i < nRecords; i++ {
q = []byte{'\xa3', uint8(i + 1)}
//log.Printf("Query: %q\n", q)
//log.Printf("Requesting measurement %d...", i+1)
n, err = s.Write(q)
if err != nil {
return items, err
}
n, err = getData(s, buf, 9)
//log.Printf("DESC> %q\n", buf[:n])
var data measurement
data.Header = int(buf[0])
data.Systolic = int(buf[1]) + 25
data.Diastolic = int(buf[2]) + 25
data.Pulse = int(buf[3])
data.Month = int(buf[4])
data.Day = int(buf[5])
data.Hour = int(buf[6])
data.Minute = int(buf[7])
data.Year = int(buf[8]) + 2000
items = append(items, data)
}
s.Close()
return items, nil
}
func loadFromJSONFile(filename string) (items []measurement, err error) {
data, err := ioutil.ReadFile(filename)
if err != nil {
return items, err
}
err = json.Unmarshal(data, &items)
return items, err
}
func mergeItems(newItems, oldItems []measurement) []measurement {
var result []measurement
var j int
// TODO: Would be better to compare dates and merge chronologically...
for _, nItem := range newItems {
result = append(result, nItem)
if j+1 <= len(oldItems) && nItem == oldItems[j] {
j++
}
}
if j+1 <= len(oldItems) {
result = append(result, oldItems[j:]...)
}
return result
}
func parseDate(dateStr string) (date time.Time, err error) {
if dateStr == "" {
return
}
var yy, mm, dd, h, m, s int
n, e := fmt.Sscanf(dateStr, "%d-%d-%d %d:%d:%d", &yy, &mm, &dd, &h, &m, &s)
if e != nil && n < 3 {
err = e
return
}
if n < 6 {
log.Printf("Date parsed with only %d fields\n", n)
}
date = time.Date(yy, time.Month(mm), dd, h, m, s, 0, time.Local)
return
}
func average(items []measurement) (measurement, error) {
var avgMeasure measurement
var avgCount int
for _, data := range items {
avgMeasure.Systolic += data.Systolic
avgMeasure.Diastolic += data.Diastolic
avgMeasure.Pulse += data.Pulse
avgCount++
}
roundDivision := func(a, b int) int {
return int(0.5 + float64(a)/float64(b))
}
if avgCount == 0 {
return avgMeasure, fmt.Errorf("cannot compute average: empty set")
}
avgMeasure.Systolic = roundDivision(avgMeasure.Systolic, avgCount)
avgMeasure.Diastolic = roundDivision(avgMeasure.Diastolic, avgCount)
avgMeasure.Pulse = roundDivision(avgMeasure.Pulse, avgCount)
return avgMeasure, nil
}
func intMedian(numbers []int) int {
middle := len(numbers) / 2
med := numbers[middle]
if len(numbers)%2 == 0 {
med = (med + numbers[middle-1]) / 2
}
return med
}
func median(items []measurement) (measurement, error) {
var med measurement
if len(items) == 0 {
return med, fmt.Errorf("cannot compute average: empty set")
}
var sys, dia, pul []int
for _, data := range items {
sys = append(sys, data.Systolic)
dia = append(dia, data.Diastolic)
pul = append(pul, data.Pulse)
}
sort.Ints(sys)
sort.Ints(dia)
sort.Ints(pul)
med.Systolic = intMedian(sys)
med.Diastolic = intMedian(dia)
med.Pulse = intMedian(pul)
return med, nil
}
func stdDeviation(items []measurement) (measurement, error) {
var sDev measurement
if len(items) <= 1 {
return sDev, fmt.Errorf("cannot compute deviation: set too small")
}
var sumSys, sumDia, sumPul float64
avg, err := average(items)
if err != nil {
return sDev, err
}
for _, data := range items {
sumSys += math.Pow(float64(data.Systolic-avg.Systolic), 2)
sumDia += math.Pow(float64(data.Diastolic-avg.Diastolic), 2)
sumPul += math.Pow(float64(data.Pulse-avg.Pulse), 2)
}
sDev.Systolic = int(math.Sqrt(sumSys / float64(len(items)-1)))
sDev.Diastolic = int(math.Sqrt(sumDia / float64(len(items)-1)))
sDev.Pulse = int(math.Sqrt(sumPul / float64(len(items)-1)))
return sDev, nil
}
func main() {
inFile := flag.String([]string{"-input-file", "i"}, "", "Input JSON file")
outFile := flag.String([]string{"-output-file", "o"}, "", "Output JSON file")
limit := flag.Uint([]string{"-limit", "l"}, 0, "Limit number of items to N first")
since := flag.String([]string{"-since"}, "",
"Filter records from date (YYYY-mm-dd HH:MM:SS)")
format := flag.String([]string{"-format", "f"}, "", "Output format (csv, json)")
avg := flag.Bool([]string{"-average", "a"}, false, "Compute average")
stats := flag.Bool([]string{"-stats"}, false, "Compute statistics")
merge := flag.Bool([]string{"-merge", "m"}, false,
"Try to merge input JSON file with fetched data")
device := flag.String([]string{"-device", "d"}, "/dev/ttyUSB0", "Serial device")
flag.Parse()
switch *format {
case "":
if *outFile == "" {
*format = "csv"
}
break
case "json", "csv":
break
default:
log.Fatal("Unknown output format. Possible choices are csv, json.")
}
startDate, err := parseDate(*since)
if err != nil {
log.Fatal("Could not parse date: ", err)
}
var items []measurement
if *inFile == "" {
// Read from device
if items, err = fetchData(*device); err != nil {
log.Fatal(err)
}
} else {
// Read from file
var fileItems []measurement
if fileItems, err = loadFromJSONFile(*inFile); err != nil {
log.Fatal(err)
}
if *merge {
if items, err = fetchData(*device); err != nil {
log.Fatal(err)
}
items = mergeItems(items, fileItems)
} else {
items = fileItems
}
}
if !startDate.IsZero() {
log.Printf("Filtering out records before %v...\n", startDate)
for i := range items {
iDate := time.Date(items[i].Year, time.Month(items[i].Month),
items[i].Day, items[i].Hour, items[i].Minute, 0, 0,
time.Local)
if iDate.Sub(startDate) < 0 {
items = items[0:i]
break
}
}
}
if *limit > 0 && len(items) > int(*limit) {
items = items[0:*limit]
}
if *format == "csv" {
for i, data := range items {
fmt.Printf("%d;%x;%d-%02d-%02d %02d:%02d;%d;%d;%d\n",
i+1, data.Header,
data.Year, data.Month, data.Day,
data.Hour, data.Minute,
data.Systolic, data.Diastolic, data.Pulse)
}
}
if *stats {
*avg = true
}
if *avg && len(items) > 0 {
avgMeasure, err := average(items)
if err != nil {
log.Println("Error:", err)
} else {
fmt.Printf("Average: %d;%d;%d\n", avgMeasure.Systolic,
avgMeasure.Diastolic, avgMeasure.Pulse)
}
}
if *stats && len(items) > 1 {
d, err := stdDeviation(items)
if err != nil {
log.Println("Error:", err)
} else {
fmt.Printf("Standard deviation: %d;%d;%d\n",
d.Systolic, d.Diastolic, d.Pulse)
}
}
if *stats && len(items) > 0 {
m, err := median(items)
if err != nil {
log.Println("Error:", err)
} else {
fmt.Printf("Median values: %d;%d;%d\n",
m.Systolic, m.Diastolic, m.Pulse)
}
}
if *format == "json" || *outFile != "" {
rawJSON, err := json.MarshalIndent(items, "", " ")
if err != nil {
log.Fatal("Error:", err)
}
if *format == "json" {
fmt.Println(string(rawJSON))
}
if *outFile != "" {
err = ioutil.WriteFile(*outFile, rawJSON, 0600)
if err != nil {
log.Println("Could not write output file:", err)
}
}
}
}