Sheets Quickstart – Go alternative (developers.google.com/sheets/api/quickstart/go)

quickstart.go

package main

import (
  "fmt"
  "log"
)

// https://docs.google.com/spreadsheets/d/1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms/edit
var SpreadsheetId = "1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms"

func getSpreadsheetValues() {
  // Prints the names and majors of students in a sample spreadsheet:
  readRange := "Class Data!A2:E"
  resp, err := getService().Spreadsheets.Values.Get(SpreadsheetId, readRange).Do()

  if err != nil {
    log.Fatalf("Unable to retrieve data from sheet. %v", err)
  }

  fmt.Println("Name, Major:")
  for _, row := range resp.Values {
    // Print columns A and E, which correspond to indices 0 and 4.
    fmt.Printf("%s, %s\n", row[0], row[4])
  }
}

service.go

package main

import (
  "fmt"
  "log"
  "google.golang.org/api/sheets/v4"
  "io/ioutil"
  "golang.org/x/oauth2/google"
  "golang.org/x/oauth2"
  "context"
)

// getTokenFromWeb uses Config to request a Token.
// It returns the retrieved Token.
func getTokenFromWeb(config *oauth2.Config) *oauth2.Token {
  authURL := config.AuthCodeURL("state-token", oauth2.AccessTypeOffline)
  fmt.Printf("Go to the following link in your browser then type the "+
      "authorization code: \n%v\n", authURL)

  var code string
  if _, err := fmt.Scan(&code); err != nil {
    log.Fatalf("Unable to read authorization code %v", err)
  }

  tok, err := config.Exchange(context.Background(), code)
  if err != nil {
    log.Fatalf("Unable to retrieve token from web %v", err)
  }
  return tok
}

func getService() (*sheets.Service, error){
  clientSecret, err := ioutil.ReadFile(ClientSecretFilename)
  if err != nil {
    log.Fatalf("Unable to read client secret file: %v", err)
  }

  config, err := google.ConfigFromJSON(clientSecret, sheets.SpreadsheetsReadonlyScope)
  if err != nil {
    log.Fatalf("Unable to parse client secret file to config: %v", err)
  }
  client := config.Client(context.Background(), getTokenFromWeb(config))
  return sheets.New(client)
}