CalDAV support (#15)

pkg/caldav/caldav.go

@@ -0,0 +1,95 @@
+package caldav
+
+import (
+	"code.vikunja.io/api/pkg/utils"
+	"strconv"
+	"time"
+)
+
+// Event holds a single caldav event
+type Event struct {
+	Summary     string
+	Description string
+	UID         string
+	Alarms      []Alarm
+
+	TimestampUnix int64
+	StartUnix     int64
+	EndUnix       int64
+}
+
+// Alarm holds infos about an alarm from a caldav event
+type Alarm struct {
+	TimeUnix    int64
+	Description string
+}
+
+// Config is the caldav calendar config
+type Config struct {
+	Name   string
+	ProdID string
+}
+
+// ParseEvents parses an array of caldav events and gives them back as string
+func ParseEvents(config *Config, events []*Event) (caldavevents string) {
+	caldavevents += `BEGIN:VCALENDAR
+VERSION:2.0
+METHOD:PUBLISH
+X-PUBLISHED-TTL:PT4H
+X-WR-CALNAME:` + config.Name + `
+PRODID:-//` + config.ProdID + `//EN`
+
+	for _, e := range events {
+
+		if e.UID == "" {
+			e.UID = makeCalDavTimeFromUnixTime(e.TimestampUnix) + utils.Sha256(e.Summary)
+		}
+
+		caldavevents += `
+BEGIN:VEVENT
+UID:` + e.UID + `
+SUMMARY:` + e.Summary + `
+DESCRIPTION:` + e.Description + `
+DTSTAMP:` + makeCalDavTimeFromUnixTime(e.TimestampUnix) + `
+DTSTART:` + makeCalDavTimeFromUnixTime(e.StartUnix) + `
+DTEND:` + makeCalDavTimeFromUnixTime(e.EndUnix)
+
+		for _, a := range e.Alarms {
+			if a.Description == "" {
+				a.Description = e.Summary
+			}
+
+			caldavevents += `
+BEGIN:VALARM
+TRIGGER:` + calcAlarmDateFromReminder(e.StartUnix, a.TimeUnix) + `
+ACTION:DISPLAY
+DESCRIPTION:` + a.Description + `
+END:VALARM`
+		}
+		caldavevents += `
+END:VEVENT`
+	}
+
+	caldavevents += `
+END:VCALENDAR` // Need a line break
+
+	return
+}
+
+func makeCalDavTimeFromUnixTime(unixtime int64) (caldavtime string) {
+	tm := time.Unix(unixtime, 0)
+	return tm.Format("20060102T150405")
+}
+
+func calcAlarmDateFromReminder(eventStartUnix, reminderUnix int64) (alarmTime string) {
+	if eventStartUnix > reminderUnix {
+		alarmTime += `-`
+	}
+	alarmTime += `PT`
+	diff := eventStartUnix - reminderUnix
+	if diff < 0 { // Make it positive
+		diff = diff * -1
+	}
+	alarmTime += strconv.Itoa(int(diff/60)) + "M"
+	return
+}

pkg/models/list.go

@@ -161,7 +161,11 @@ type ListTasksDummy struct {
 
 // ReadAll gets all tasks for a user
 func (lt *ListTasksDummy) ReadAll(u *User) (interface{}, error) {
+	return GetTasksByUser(u)
+}
 
+//GetTasksByUser returns all tasks for a user
+func GetTasksByUser(u *User) (tasks []*ListTask, err error) {
 	// Get all lists
 	lists, err := getRawListsForUser(u)
 	if err != nil {
@@ -175,7 +179,6 @@ func (lt *ListTasksDummy) ReadAll(u *User) (interface{}, error) {
 	}
 
 	// Then return all tasks for that lists
-	var tasks []*ListTask
 	if err := x.In("list_id", listIDs).Find(&tasks); err != nil {
 		return nil, err
 	}

pkg/routes/api/v1/caldav.go

@@ -0,0 +1,74 @@
+package v1
+
+import (
+	"code.vikunja.io/api/pkg/caldav"
+	"code.vikunja.io/api/pkg/models"
+	"code.vikunja.io/api/pkg/routes/crud"
+	"github.com/labstack/echo"
+	"net/http"
+	"time"
+)
+
+// Caldav returns a caldav-readable format with all tasks
+func Caldav(c echo.Context) error {
+
+	// swagger:operation GET /tasks/caldav list caldavTasks
+	// ---
+	// summary: Get all tasks as caldav
+	// responses:
+	//   "200":
+	//     "$ref": "#/responses/Message"
+	//   "400":
+	//     "$ref": "#/responses/Message"
+	//   "500":
+	//     "$ref": "#/responses/Message"
+
+	// Request basic auth
+	user, pass, ok := c.Request().BasicAuth()
+
+	// Check credentials
+	creds := &models.UserLogin{
+		Username: user,
+		Password: pass,
+	}
+	u, err := models.CheckUserCredentials(creds)
+
+	if !ok || err != nil {
+		c.Response().Header().Set("WWW-Authenticate", `Basic realm="Vikunja cal"`)
+		return c.String(http.StatusUnauthorized, "Unauthorized.")
+	}
+
+	// Get all tasks for that user
+	tasks, err := models.GetTasksByUser(&u)
+	if err != nil {
+		return crud.HandleHTTPError(err)
+	}
+
+	hour := int64(time.Hour.Seconds())
+	var caldavTasks []*caldav.Event
+	for _, t := range tasks {
+		if t.DueDateUnix != 0 {
+			event := &caldav.Event{
+				Summary:       t.Text,
+				Description:   t.Description,
+				UID:           "",
+				TimestampUnix: t.Updated,
+				StartUnix:     t.DueDateUnix,
+				EndUnix:       t.DueDateUnix + hour,
+			}
+
+			if t.ReminderUnix != 0 {
+				event.Alarms = append(event.Alarms, caldav.Alarm{TimeUnix: t.ReminderUnix})
+			}
+
+			caldavTasks = append(caldavTasks, event)
+		}
+	}
+
+	caldavConfig := &caldav.Config{
+		Name:   "Vikunja Calendar for " + u.Username,
+		ProdID: "Vikunja Todo App",
+	}
+
+	return c.String(http.StatusOK, caldav.ParseEvents(caldavConfig, caldavTasks))
+}

pkg/routes/routes.go

@@ -41,6 +41,8 @@ import (
 func NewEcho() *echo.Echo {
 	e := echo.New()
 
+	e.HideBanner = true
+
 	// Logger
 	e.Use(middleware.LoggerWithConfig(middleware.LoggerConfig{
 		Format: "${time_rfc3339_nano}: ${remote_ip} ${method} ${status} ${uri} ${latency_human} - ${user_agent}\n",
@@ -69,6 +71,9 @@ func RegisterRoutes(e *echo.Echo) {
 	a.POST("/user/password/reset", apiv1.UserResetPassword)
 	a.POST("/user/confirm", apiv1.UserConfirmEmail)
 
+	// Caldav, with auth
+	a.GET("/tasks/caldav", apiv1.Caldav)
+
 	// ===== Routes with Authetification =====
 	// Authetification
 	a.Use(middleware.JWT([]byte(viper.GetString("service.JWTSecret"))))

pkg/utils/sha256.go

@@ -0,0 +1,11 @@
+package utils
+
+import (
+	"crypto/sha256"
+	"fmt"
+)
+
+// Sha256 calculates a sha256 hash from a string
+func Sha256(cleartext string) string {
+	return fmt.Sprintf("%x", sha256.Sum256([]byte(cleartext)))[:45]
+}