Initial commit

.gitignore

@@ -0,0 +1,2 @@
+credentials.json
+token.json

auth.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+
+	"golang.org/x/net/context"
+	"golang.org/x/oauth2"
+)
+
+// Retrieve a token, saves the token, then returns the generated client.
+func getClient(config *oauth2.Config) (*http.Client, error) {
+	// The file token.json stores the user's access and refresh tokens, and is
+	// created automatically when the authorization flow completes for the first
+	// time.
+	tokFile := "token.json"
+	tok, err := tokenFromFile(tokFile)
+	if err != nil {
+		tok, err = getTokenFromWeb(config)
+		if err != nil {
+			return nil, err
+		}
+
+		err = saveToken(tokFile, tok)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return config.Client(context.Background(), tok), nil
+}
+
+// Request a token from the web, then returns the retrieved token.
+func getTokenFromWeb(config *oauth2.Config) (*oauth2.Token, error) {
+	authURL := config.AuthCodeURL("state-token", oauth2.AccessTypeOffline)
+	log.Printf("Go to the following link in your browser then type the authorization code: \n%v", authURL)
+
+	var authCode string
+	if _, err := fmt.Scan(&authCode); err != nil {
+		return nil, err
+	}
+
+	tok, err := config.Exchange(context.TODO(), authCode)
+	if err != nil {
+		return nil, err
+	}
+	return tok, nil
+}
+
+// Retrieves a token from a local file.
+func tokenFromFile(file string) (*oauth2.Token, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	tok := &oauth2.Token{}
+	err = json.NewDecoder(f).Decode(tok)
+	return tok, err
+}
+
+// Saves a token to a file path.
+func saveToken(path string, token *oauth2.Token) error {
+	f, err := os.OpenFile(path, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	json.NewEncoder(f).Encode(token)
+
+	return nil
+}

main.go

@@ -0,0 +1,180 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"time"
+
+	"golang.org/x/oauth2/google"
+	"google.golang.org/api/calendar/v3"
+)
+
+var calName = flag.String("calendar", "", "name of calendar")
+
+var students = []string{
+	"oliver.park@heliosns.org",
+}
+
+var classes = []Class {
+	Class{
+		Summary: "Test 2",
+		Start: "22:00",
+		End: "22:30",
+		Days: []time.Weekday{time.Monday, time.Tuesday, time.Wednesday, time.Thursday},
+		Zoom: "https://us02web.zoom.us/j/2274643506?pwd=Nm5NUXMwOVJKbEUzNE5VSkZCQzJ2UT09",
+	},
+}
+
+type Class struct {
+	Summary string
+	Start string
+	End string
+	Students []string
+	Days []time.Weekday
+	Zoom string
+}
+
+func main() {
+	flag.Parse()
+
+	b, err := ioutil.ReadFile("credentials.json")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// If modifying these scopes, delete your previously saved token.json.
+	config, err := google.ConfigFromJSON(b, calendar.CalendarScope)
+	if err != nil {
+		log.Fatal(err)
+	}
+	client, err := getClient(config)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	srv, err := calendar.New(client)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	calendars, err := srv.CalendarList.List().Do()
+	if err != nil {
+		log.Fatal(err)
+	}
+	var myCal *calendar.CalendarListEntry
+	for _, item := range calendars.Items {
+		if item.Summary == *calName {
+			myCal = item
+			break
+		}
+	}
+	if myCal == nil {
+		log.Fatalf("calendar '%s' not found", *calName)
+	}
+
+	loc, err := time.LoadLocation("US/Pacific")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	now := time.Now().In(loc)
+
+	dateStr := now.Format("2006-01-02")
+
+	// TOOD: loop through days
+
+	for _, class := range classes {
+		found := false
+		for _, day := range class.Days {
+			if day == now.Weekday() {
+				found = true
+				break
+			}
+		}
+		if !found {
+			continue
+		}
+
+		ev := &calendar.Event{
+			Summary: class.Summary,
+			Start: &calendar.EventDateTime{
+				DateTime: fmt.Sprintf("%sT%s:00", dateStr, class.Start),
+				TimeZone: "US/Pacific",
+			},
+			End: &calendar.EventDateTime{
+				DateTime: fmt.Sprintf("%sT%s:00", dateStr, class.End),
+				TimeZone: "US/Pacific",
+			},
+			Attendees: []*calendar.EventAttendee{},
+		}
+
+		attendees := class.Students
+		if len(attendees) == 0 {
+			attendees = students
+		}
+
+		for _, student := range attendees {
+			ev.Attendees = append(
+				ev.Attendees,
+				&calendar.EventAttendee{
+					Email: student,
+				},
+			)
+		}
+
+		if class.Zoom != "" {
+			ev.Description = fmt.Sprintf(`Zoom: %s`, class.Zoom)
+		}
+
+		_, err := srv.Events.Insert(myCal.Id, ev).Do()
+		if err != nil {
+			log.Fatal(err)
+		}
+	}
+
+
+	/*
+	ev := &calendar.Event{
+		Summary: "Test event",
+		Start: &calendar.EventDateTime{
+			DateTime: "2020-09-09T16:00:00",
+			TimeZone: "US/Pacific",
+		},
+		End: &calendar.EventDateTime{
+			DateTime: "2020-09-09T17:00:00",
+			TimeZone: "US/Pacific",
+		},
+		Attendees: []*calendar.EventAttendee{
+			&calendar.EventAttendee{
+				Email: "oliver.park@heliosns.org",
+			},
+		},
+	}
+
+	res, err := srv.Events.Insert(myCal.Id, ev).Do()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	log.Printf("%#v", res)
+	*/
+
+	/*
+	t := time.Now().Format(time.RFC3339)
+	events, err := srv.Events.List(myCal.Id).ShowDeleted(false).
+		SingleEvents(true).TimeMin(t).MaxResults(250).OrderBy("startTime").Do()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for _, item := range events.Items {
+		date := item.Start.DateTime
+		if date == "" {
+			date = item.Start.Date
+		}
+		log.Printf("%v (%v)", item.Summary, date)
+	}
+	*/
+}