Related
For the below type of inputs in golang coding interviews, what is the best way to get the input?
Input:
3
hello elloh
test estt
tier riet
I found two methods:
Method 1:
reader := bufio.NewReader(os.Stdin)
var lines []string
for {
line,err := reader.ReadString('\n') //this reads only one read
if err != nil {
log.Fatal(err)
}
if len(strings.TrimSpace(line)) == 0 {
break
}
line_s := strings.Split(line, " ")
lines = append(lines, line_s...)
}
Method 2:
bytes, err := ioutil.ReadAll(os.Stdin)
fmt.Println(len(bytes))
if err == nil {
input := strings.Split(string(bytes), "\n")
count, _ := strconv.Atoi(input[0])
fmt.Println(input)
var lines []string
for i := 1; i < count; i++ {
line := strings.Split(input[i], " ")
lines = append(lines, line...)
}
fmt.Println(lines)
}
But not sure how to end getting input from stdin in Method2.
Please suggest the best method to get input.
Use bufio.Scanner to read input. Use a function to encapsulate complexity and implementation details. For example,
package main
import (
"bufio"
"fmt"
"os"
"strconv"
"strings"
)
func readData(s *bufio.Scanner) ([][]string, error) {
var data [][]string
if !s.Scan() {
return nil, s.Err()
}
nLine, err := strconv.Atoi(strings.TrimSpace(s.Text()))
if err != nil {
return nil, err
}
for ; nLine > 0 && s.Scan(); nLine-- {
data = append(data, strings.Fields(s.Text()))
}
if err := s.Err(); err != nil {
return nil, err
}
if nLine != 0 {
err := fmt.Errorf("missing %d lines of data", nLine)
return nil, err
}
return data, nil
}
func main() {
s := bufio.NewScanner(os.Stdin)
data, err := readData(s)
if err != nil {
fmt.Fprintln(os.Stderr, err)
os.Exit(1)
}
fmt.Println(len(data))
for _, datum := range data {
fmt.Println(datum)
}
}
https://go.dev/play/p/0Xwp3-hwGyK
3
hello elloh
test estt
tier riet
3
[hello elloh]
[test estt]
[tier riet]
I was trying to test a bit with Redis for the first time and I bumped into some confusion with HGET/HSET/HGETALL. My main problem was that I needed to store time, and I wanted to use a hash as I'll continuously update the time.
At first I read about how a MarshalBinary function such as this would save me:
func (f Foo) MarshalBinary() ([]byte, error) {
return json.Marshal(f)
}
What that did was that it saved the struct as a json string, but only as a string and not as an actual Redis hash. What I ended up doing in the end was a fairly large boilerplate code that makes my struct I want to save into a map, and that one is properly stored as a hash in Redis.
type Foo struct {
Number int `json:"number"`
ATime time.Time `json:"atime"`
String string `json:"astring"`
}
func (f Foo) toRedis() map[string]interface{} {
res := make(map[string]interface{})
rt := reflect.TypeOf(f)
rv := reflect.ValueOf(f)
if rt.Kind() == reflect.Ptr {
rt = rt.Elem()
rv = rv.Elem()
}
for i := 0; i < rt.NumField(); i++ {
f := rt.Field(i)
v := rv.Field(i)
switch t := v.Interface().(type) {
case time.Time:
res[f.Tag.Get("json")] = t.Format(time.RFC3339)
default:
res[f.Tag.Get("json")] = t
}
}
return res
}
Then to parse back into my Foo struct when calling HGetAll(..).Result(), I'm getting the result as a map[string]string and create a new Foo with these functions:
func setRequestParam(arg *Foo, i int, value interface{}) {
v := reflect.ValueOf(arg).Elem()
f := v.Field(i)
if f.IsValid() {
if f.CanSet() {
if f.Kind() == reflect.String {
f.SetString(value.(string))
return
} else if f.Kind() == reflect.Int {
f.Set(reflect.ValueOf(value))
return
} else if f.Kind() == reflect.Struct {
f.Set(reflect.ValueOf(value))
}
}
}
}
func fromRedis(data map[string]string) (f Foo) {
rt := reflect.TypeOf(f)
rv := reflect.ValueOf(f)
for i := 0; i < rt.NumField(); i++ {
field := rt.Field(i)
v := rv.Field(i)
switch v.Interface().(type) {
case time.Time:
if val, ok := data[field.Tag.Get("json")]; ok {
if ti, err := time.Parse(time.RFC3339, val); err == nil {
setRequestParam(&f, i, ti)
}
}
case int:
if val, ok := data[field.Tag.Get("json")]; ok {
in, _ := strconv.ParseInt(val, 10, 32)
setRequestParam(&f, i, int(in))
}
default:
if val, ok := data[field.Tag.Get("json")]; ok {
setRequestParam(&f, i, val)
}
}
}
return
}
The whole code in its ungloryness is here
I'm thinking that there must be a saner way to solve this problem? Or am I forced to do something like this? The struct I need to store only contains ints, strings and time.Times.
*edit
The comment field is a bit short so doing an edit instead:
I did originally solve it like 'The Fool' suggested in comments and as an answer. The reason I changed to the above part, while more complex a solution, I think it's more robust for changes. If I go with a hard coded map solution, I'd "have to" have:
Constants with hash keys for the fields, since they'll be used at least in two places (from and to Redis), it'll be a place for silly mistakes not picked up by the compiler. Can of course skip that but knowing my own spelling it's likely to happen
If someone just wants to add a new field and doesn't know the code well, it will compile just fine but the new field won't be added in Redis. An easy mistake to do, especially for junior developers being a bit naive, or seniors with too much confidence.
I can put these helper functions in a library, and things will just magically work for all our code when a time or complex type is needed.
My intended question/hope though was: Do I really have to jump through hoops like this to store time in Redis hashes with go? Fair, time.Time isn't a primitive and Redis isn't a (no)sql database, but I would consider timestamps in cache a very common use case (in my case a heartbeat to keep track of timed out sessions together with metadata enough to permanently store it, thus the need to update them). But maybe I'm misusing Redis, and I should rather have two entries, one for the data and one for the timestamp, which would then leave me with two simple get/set functions taking in time.Time and returning time.Time.
You can use redigo/redis#Args.AddFlat to convert struct to redis hash we can map the value using redis tag.
package main
import (
"fmt"
"time"
"github.com/gomodule/redigo/redis"
)
type Foo struct {
Number int64 `json:"number" redis:"number"`
ATime time.Time `json:"atime" redis:"atime"`
AString string `json:"astring" redis:"astring"`
}
func main() {
c, err := redis.Dial("tcp", ":6379")
if err != nil {
fmt.Println(err)
return
}
defer c.Close()
t1 := time.Now().UTC()
var foo Foo
foo.Number = 10000000000
foo.ATime = t1
foo.AString = "Hello"
tmp := redis.Args{}.Add("id1").AddFlat(&foo)
if _, err := c.Do("HMSET", tmp...); err != nil {
fmt.Println(err)
return
}
v, err := redis.StringMap(c.Do("HGETALL", "id1"))
if err != nil {
fmt.Println(err)
return
}
fmt.Printf("%#v\n", v)
}
Then to update ATime you can use redis HSET
if _, err := c.Do("HMSET", "id1", "atime", t1.Add(-time.Hour * (60 * 60 * 24))); err != nil {
fmt.Println(err)
return
}
And to retrieve it back to struct we have to do some reflect magic
func structFromMap(src map[string]string, dst interface{}) error {
dt := reflect.TypeOf(dst).Elem()
dv := reflect.ValueOf(dst).Elem()
for i := 0; i < dt.NumField(); i++ {
sf := dt.Field(i)
sv := dv.Field(i)
if v, ok := src[strings.ToLower(sf.Name)]; ok {
switch sv.Interface().(type) {
case time.Time:
format := "2006-01-02 15:04:05 -0700 MST"
ti, err := time.Parse(format, v)
if err != nil {
return err
}
sv.Set(reflect.ValueOf(ti))
case int, int64:
x, err := strconv.ParseInt(v, 10, sv.Type().Bits())
if err != nil {
return err
}
sv.SetInt(x)
default:
sv.SetString(v)
}
}
}
return nil
}
Final Code
package main
import (
"fmt"
"time"
"reflect"
"strings"
"strconv"
"github.com/gomodule/redigo/redis"
)
type Foo struct {
Number int64 `json:"number" redis:"number"`
ATime time.Time `json:"atime" redis:"atime"`
AString string `json:"astring" redis:"astring"`
}
func main() {
c, err := redis.Dial("tcp", ":6379")
if err != nil {
fmt.Println(err)
return
}
defer c.Close()
t1 := time.Now().UTC()
var foo Foo
foo.Number = 10000000000
foo.ATime = t1
foo.AString = "Hello"
tmp := redis.Args{}.Add("id1").AddFlat(&foo)
if _, err := c.Do("HMSET", tmp...); err != nil {
fmt.Println(err)
return
}
v, err := redis.StringMap(c.Do("HGETALL", "id1"))
if err != nil {
fmt.Println(err)
return
}
fmt.Printf("%#v\n", v)
if _, err := c.Do("HMSET", "id1", "atime", t1.Add(-time.Hour * (60 * 60 * 24))); err != nil {
fmt.Println(err)
return
}
var foo2 Foo
structFromMap(v, &foo2)
fmt.Printf("%#v\n", foo2)
}
func structFromMap(src map[string]string, dst interface{}) error {
dt := reflect.TypeOf(dst).Elem()
dv := reflect.ValueOf(dst).Elem()
for i := 0; i < dt.NumField(); i++ {
sf := dt.Field(i)
sv := dv.Field(i)
if v, ok := src[strings.ToLower(sf.Name)]; ok {
switch sv.Interface().(type) {
case time.Time:
format := "2006-01-02 15:04:05 -0700 MST"
ti, err := time.Parse(format, v)
if err != nil {
return err
}
sv.Set(reflect.ValueOf(ti))
case int, int64:
x, err := strconv.ParseInt(v, 10, sv.Type().Bits())
if err != nil {
return err
}
sv.SetInt(x)
default:
sv.SetString(v)
}
}
}
return nil
}
Note: The struct field name is matched with the redis tag
For example, we have 3 CSV files and common for all is Email column. In first file are Name and Email, in another are Email (plus different info) and no Name field. So, if I need to fill in 2 and 3 files field Name based on the correspondence of the Name and Đ•mail from the first file than... I wrote code like this:
package main
import (
"fmt"
"io/ioutil"
"log"
"path/filepath"
"strings"
"github.com/jszwec/csvutil"
)
type User struct {
Name string `csv:"name"`
Email string `csv:"email"`
}
type Good struct {
User
Dt string `csv:"details"`
}
type Strange struct {
User
St string `csv:"status"`
Dt string `csv:"details"`
}
var lst map[string]string
func readCSV(fn string, dat interface{}) error {
raw, err := ioutil.ReadFile(fn)
if err != nil {
return fmt.Errorf("Cannot read CSV: %w", err)
}
if err := csvutil.Unmarshal(raw, dat); err != nil {
return fmt.Errorf("Cannot unmarshal CSV: %w", err)
}
return nil
}
func fixNames(fl string, in interface{}) error {
if err := readCSV(fl, in); err != nil {
return fmt.Errorf("CSV: %w", err)
}
switch in.(type) {
case *[]Good:
var vals []Good
for _, v := range *in.(*[]Good) {
v.Name = lst[strings.TrimSpace(strings.ToLower(v.Email))]
vals = append(vals, v)
}
in = vals
case *[]Strange:
var vals []Strange
for _, v := range *in.(*[]Strange) {
v.Name = lst[strings.TrimSpace(strings.ToLower(v.Email))]
vals = append(vals, v)
}
in = vals
}
b, err := csvutil.Marshal(in)
if err != nil {
return fmt.Errorf("Cannot marshal CSV: %w", err)
}
ext := filepath.Ext(fl)
bas := filepath.Base(fl)
err = ioutil.WriteFile(bas[:len(bas)-len(ext)]+"-XIAOSE"+ext, b, 0644)
if err != nil {
return fmt.Errorf("Cannot save CSV: %w", err)
}
return nil
}
func main() {
var users []User
if err := readCSV("./Guitar_Contacts.csv", &users); err != nil {
log.Fatalf("CSV: %s", err)
}
lst = make(map[string]string)
for _, v := range users {
lst[strings.TrimSpace(strings.ToLower(v.Email))] = v.Name
}
var usersGood []Good
if err := fixNames("./Guitar-Good.csv", &usersGood); err != nil {
log.Fatalf("fix: %s", err)
}
var usersStrange []Strange
if err := fixNames("./Guitar-Uknown.csv", &usersStrange); err != nil {
log.Fatalf("fix: %s", err)
}
fmt.Println("OK")
}
in this code I don't like part in func fixNames where is switch:
switch in.(type) {
case *[]Good:
var vals []Good
for _, v := range *in.(*[]Good) {
v.Name = lst[strings.TrimSpace(strings.ToLower(v.Email))]
vals = append(vals, v)
}
in = vals
case *[]Strange:
var vals []Strange
for _, v := range *in.(*[]Strange) {
v.Name = lst[strings.TrimSpace(strings.ToLower(v.Email))]
vals = append(vals, v)
}
in = vals
}
because I just repeat code in part where *in.(SOME_TYPE). I want one loop and one action for different types, structs where are Name and Email fields...
Also was idea to do it with reflection smth. like this:
v := reflect.ValueOf(in)
v = v.Elem()
for i := 0; i < v.Len(); i++ {
fmt.Println(v.Index(i))
}
but I do not know what to do next, how to add in that v value for Name
You don't need reflection for this particular case. You can clean the code up by realizing that you are only working on the User part of the structs, and that you can simplify the type switch:
fix:=func(in *User) {
in.Name = lst[strings.TrimSpace(strings.ToLower(in.Email))]
}
switch k:=in.(type) {
case *[]Good:
for i := range *k {
fix( &(*k)[i].User )
}
case *[]Strange:
for i := range *k {
fix( &(*k)[i].User )
}
}
You have to repeat the for loop, but above code does the correction in place.
You can clean up a bit more by not passing a reference to the slice.
With reflect package, you can do that like this.
func fixNames(fl string, in interface{}) error {
//other code
v := reflect.ValueOf(in)
if v.Kind() == reflect.Ptr {
arr := v.Elem()
fmt.Println(arr.Len())
if arr.Kind() == reflect.Slice || arr.Kind() == reflect.Array {
for i := 0; i < arr.Len(); i++ {
elem := arr.Index(i)
f := elem.FieldByName("Name")
f.SetString("NameOfUser")
}
}
}
// other code
}
Also playground example: https://play.golang.org/p/KrGvLVprslH
Assuming we have two yaml files
master.yaml
someProperty: "someVaue"
anotherProperty: "anotherValue"
override.yaml
someProperty: "overriddenVaue"
Is it possible to unmarshall, merge, and then write those changes to a file without having to define a struct for every property in the yaml file?
The master file has over 500 properties in it that are not at all important to the service at this point of execution, so ideally I'd be able to just unmarshal into a map, do a merge and write out in yaml again but I'm relatively new to go so wanted some opinions.
I've got some code to read the yaml into an interface but i'm unsure on the best approach to then merge the two.
var masterYaml interface{}
yamlBytes, _ := ioutil.ReadFile("master.yaml")
yaml.Unmarshal(yamlBytes, &masterYaml)
var overrideYaml interface{}
yamlBytes, _ = ioutil.ReadFile("override.yaml")
yaml.Unmarshal(yamlBytes, &overrideYaml)
I've looked into libraries like mergo but i'm not sure if that's the right approach.
I'm hoping that after the master I would be able to write out to file with properties
someProperty: "overriddenVaue"
anotherProperty: "anotherValue"
Assuming that you just want to merge at the top level, you can unmarshal into maps of type map[string]interface{}, as follows:
package main
import (
"io/ioutil"
"gopkg.in/yaml.v2"
)
func main() {
var master map[string]interface{}
bs, err := ioutil.ReadFile("master.yaml")
if err != nil {
panic(err)
}
if err := yaml.Unmarshal(bs, &master); err != nil {
panic(err)
}
var override map[string]interface{}
bs, err = ioutil.ReadFile("override.yaml")
if err != nil {
panic(err)
}
if err := yaml.Unmarshal(bs, &override); err != nil {
panic(err)
}
for k, v := range override {
master[k] = v
}
bs, err = yaml.Marshal(master)
if err != nil {
panic(err)
}
if err := ioutil.WriteFile("merged.yaml", bs, 0644); err != nil {
panic(err)
}
}
For a broader solution (with n input files), you can use this function. I have used #robox answer to do my solution:
func ReadValues(filenames ...string) (string, error) {
if len(filenames) <= 0 {
return "", errors.New("You must provide at least one filename for reading Values")
}
var resultValues map[string]interface{}
for _, filename := range filenames {
var override map[string]interface{}
bs, err := ioutil.ReadFile(filename)
if err != nil {
log.Info(err)
continue
}
if err := yaml.Unmarshal(bs, &override); err != nil {
log.Info(err)
continue
}
//check if is nil. This will only happen for the first filename
if resultValues == nil {
resultValues = override
} else {
for k, v := range override {
resultValues[k] = v
}
}
}
bs, err := yaml.Marshal(resultValues)
if err != nil {
log.Info(err)
return "", err
}
return string(bs), nil
}
So for this example you should call it with this order:
result, _ := ReadValues("master.yaml", "overwrite.yaml")
In the case you have an extra file newFile.yaml, you could also use this function:
result, _ := ReadValues("master.yaml", "overwrite.yaml", "newFile.yaml")
DEEP MERGE TWO YAML FILES
package main
import (
"fmt"
"io/ioutil"
"sigs.k8s.io/yaml"
)
func main() {
// declare two map to hold the yaml content
base := map[string]interface{}{}
currentMap := map[string]interface{}{}
// read one yaml file
data, _ := ioutil.ReadFile("conf.yaml")
if err := yaml.Unmarshal(data, &base); err != nil {
}
// read another yaml file
data1, _ := ioutil.ReadFile("conf1.yaml")
if err := yaml.Unmarshal(data1, ¤tMap); err != nil {
}
// merge both yaml data recursively
base = mergeMaps(base, currentMap)
// print merged map
fmt.Println(base)
}
func mergeMaps(a, b map[string]interface{}) map[string]interface{} {
out := make(map[string]interface{}, len(a))
for k, v := range a {
out[k] = v
}
for k, v := range b {
if v, ok := v.(map[string]interface{}); ok {
if bv, ok := out[k]; ok {
if bv, ok := bv.(map[string]interface{}); ok {
out[k] = mergeMaps(bv, v)
continue
}
}
}
out[k] = v
}
return out
}
Here is a code snippet that reads CSV file:
func parseLocation(file string) (map[string]Point, error) {
f, err := os.Open(file)
defer f.Close()
if err != nil {
return nil, err
}
lines, err := csv.NewReader(f).ReadAll()
if err != nil {
return nil, err
}
locations := make(map[string]Point)
for _, line := range lines {
name := line[0]
lat, laterr := strconv.ParseFloat(line[1], 64)
if laterr != nil {
return nil, laterr
}
lon, lonerr := strconv.ParseFloat(line[2], 64)
if lonerr != nil {
return nil, lonerr
}
locations[name] = Point{lat, lon}
}
return locations, nil
}
Is there a way to improve readability of this code? if and nil noise.
Go now has a csv package for this. Its is encoding/csv. You can find the docs here: https://golang.org/pkg/encoding/csv/
There are a couple of good examples in the docs. Here is a helper method I created to read a csv file and returns its records.
package main
import (
"encoding/csv"
"fmt"
"log"
"os"
)
func readCsvFile(filePath string) [][]string {
f, err := os.Open(filePath)
if err != nil {
log.Fatal("Unable to read input file " + filePath, err)
}
defer f.Close()
csvReader := csv.NewReader(f)
records, err := csvReader.ReadAll()
if err != nil {
log.Fatal("Unable to parse file as CSV for " + filePath, err)
}
return records
}
func main() {
records := readCsvFile("../tasks.csv")
fmt.Println(records)
}
Go is a very verbose language, however you could use something like this:
// predeclare err
func parseLocation(file string) (locations map[string]*Point, err error) {
f, err := os.Open(file)
if err != nil {
return nil, err
}
defer f.Close() // this needs to be after the err check
lines, err := csv.NewReader(f).ReadAll()
if err != nil {
return nil, err
}
//already defined in declaration, no need for :=
locations = make(map[string]*Point, len(lines))
var lat, lon float64 //predeclare lat, lon
for _, line := range lines {
// shorter, cleaner and since we already have lat and err declared, we can do this.
if lat, err = strconv.ParseFloat(line[1], 64); err != nil {
return nil, err
}
if lon, err = strconv.ParseFloat(line[2], 64); err != nil {
return nil, err
}
locations[line[0]] = &Point{lat, lon}
}
return locations, nil
}
//edit
A more efficient and proper version was posted by #Dustin in the comments, I'm adding it here for completeness sake:
func parseLocation(file string) (map[string]*Point, error) {
f, err := os.Open(file)
if err != nil {
return nil, err
}
defer f.Close()
csvr := csv.NewReader(f)
locations := map[string]*Point{}
for {
row, err := csvr.Read()
if err != nil {
if err == io.EOF {
err = nil
}
return locations, err
}
p := &Point{}
if p.lat, err = strconv.ParseFloat(row[1], 64); err != nil {
return nil, err
}
if p.lon, err = strconv.ParseFloat(row[2], 64); err != nil {
return nil, err
}
locations[row[0]] = p
}
}
playground
I basically copied my answer from here: https://www.dotnetperls.com/csv-go. For me, this was a better answer than what I found on stackoverflow.
import (
"bufio"
"encoding/csv"
"os"
"fmt"
"io"
)
func ReadCsvFile(filePath string) {
// Load a csv file.
f, _ := os.Open(filePath)
// Create a new reader.
r := csv.NewReader(f)
for {
record, err := r.Read()
// Stop at EOF.
if err == io.EOF {
break
}
if err != nil {
panic(err)
}
// Display record.
// ... Display record length.
// ... Display all individual elements of the slice.
fmt.Println(record)
fmt.Println(len(record))
for value := range record {
fmt.Printf(" %v\n", record[value])
}
}
}
I also dislike the verbosity of the default Reader, so I made a new type that is
similar to bufio#Scanner:
package main
import "encoding/csv"
import "io"
type Scanner struct {
Reader *csv.Reader
Head map[string]int
Row []string
}
func NewScanner(o io.Reader) Scanner {
csv_o := csv.NewReader(o)
a, e := csv_o.Read()
if e != nil {
return Scanner{}
}
m := map[string]int{}
for n, s := range a {
m[s] = n
}
return Scanner{Reader: csv_o, Head: m}
}
func (o *Scanner) Scan() bool {
a, e := o.Reader.Read()
o.Row = a
return e == nil
}
func (o Scanner) Text(s string) string {
return o.Row[o.Head[s]]
}
Example:
package main
import "strings"
func main() {
s := `Month,Day
January,Sunday
February,Monday`
o := NewScanner(strings.NewReader(s))
for o.Scan() {
println(o.Text("Month"), o.Text("Day"))
}
}
https://golang.org/pkg/encoding/csv
You can also read contents of a directory to load all the CSV files. And then read all those CSV files 1 by 1 with goroutines
csv file:
101,300.00,11000901,1155686400
102,250.99,11000902,1432339200
main.go file:
const sourcePath string = "./source"
func main() {
dir, _ := os.Open(sourcePath)
files, _ := dir.Readdir(-1)
for _, file := range files {
fmt.Println("SINGLE FILE: ")
fmt.Println(file.Name())
filePath := sourcePath + "/" + file.Name()
f, _ := os.Open(filePath)
defer f.Close()
// os.Remove(filePath)
//func
go func(file io.Reader) {
records, _ := csv.NewReader(file).ReadAll()
for _, row := range records {
fmt.Println(row)
}
}(f)
time.Sleep(10 * time.Millisecond)// give some time to GO routines for execute
}
}
And the OUTPUT will be:
$ go run main.go
SINGLE FILE:
batch01.csv
[101 300.00 11000901 1155686400]
[102 250.99 11000902 1432339200]
----------------- -------------- ---------------------- -------
---------------- ------------------- ----------- --------------
Below example with the Invoice struct
func main() {
dir, _ := os.Open(sourcePath)
files, _ := dir.Readdir(-1)
for _, file := range files {
fmt.Println("SINGLE FILE: ")
fmt.Println(file.Name())
filePath := sourcePath + "/" + file.Name()
f, _ := os.Open(filePath)
defer f.Close()
go func(file io.Reader) {
records, _ := csv.NewReader(file).ReadAll()
for _, row := range records {
invoice := new(Invoice)
invoice.InvoiceNumber = row[0]
invoice.Amount, _ = strconv.ParseFloat(row[1], 64)
invoice.OrderID, _ = strconv.Atoi(row[2])
unixTime, _ := strconv.ParseInt(row[3], 10, 64)
invoice.Date = time.Unix(unixTime, 0)
fmt.Printf("Received invoice `%v` for $ %.2f \n", invoice.InvoiceNumber, invoice.Amount)
}
}(f)
time.Sleep(10 * time.Millisecond)
}
}
type Invoice struct {
InvoiceNumber string
Amount float64
OrderID int
Date time.Time
}