caldav: add Client.QueryCalendar

caldav/caldav.go

@@ -3,9 +3,34 @@
 // CalDAV is defined in RFC 4791.
 package caldav
 
+import (
+	"time"
+)
+
 type Calendar struct {
 	Path            string
 	Name            string
 	Description     string
 	MaxResourceSize int64
 }
+
+type CalendarCompRequest struct {
+	Name string
+
+	AllProps bool
+	Props    []string
+
+	AllComps bool
+	Comps    []CalendarCompRequest
+}
+
+type CalendarQuery struct {
+	Comp CalendarCompRequest
+}
+
+type CalendarObject struct {
+	Path    string
+	ModTime time.Time
+	ETag    string
+	Data    []byte
+}

caldav/client.go

@@ -3,6 +3,8 @@ package caldav
 import (
 	"fmt"
 	"net/http"
+	"strconv"
+	"time"
 
 	"github.com/emersion/go-webdav"
 	"github.com/emersion/go-webdav/internal"
@@ -102,3 +104,98 @@ func (c *Client) FindCalendars(calendarHomeSet string) ([]Calendar, error) {
 
 	return l, nil
 }
+
+func encodeCalendarCompReq(c *CalendarCompRequest) (*comp, error) {
+	encoded := comp{Name: c.Name}
+
+	if c.AllProps {
+		encoded.Allprop = &struct{}{}
+	}
+	for _, name := range c.Props {
+		encoded.Prop = append(encoded.Prop, prop{Name: name})
+	}
+
+	if c.AllComps {
+		encoded.Allcomp = &struct{}{}
+	}
+	for _, child := range c.Comps {
+		encodedChild, err := encodeCalendarCompReq(&child)
+		if err != nil {
+			return nil, err
+		}
+		encoded.Comp = append(encoded.Comp, *encodedChild)
+	}
+
+	return &encoded, nil
+}
+
+func encodeCalendarReq(c *CalendarCompRequest) (*internal.Prop, error) {
+	compReq, err := encodeCalendarCompReq(c)
+	if err != nil {
+		return nil, err
+	}
+
+	calDataReq := calendarDataReq{Comp: compReq}
+
+	getLastModReq := internal.NewRawXMLElement(internal.GetLastModifiedName, nil, nil)
+	getETagReq := internal.NewRawXMLElement(internal.GetETagName, nil, nil)
+	return internal.EncodeProp(&calDataReq, getLastModReq, getETagReq)
+}
+
+func decodeCalendarObjectList(ms *internal.Multistatus) ([]CalendarObject, error) {
+	addrs := make([]CalendarObject, 0, len(ms.Responses))
+	for _, resp := range ms.Responses {
+		path, err := resp.Path()
+		if err != nil {
+			return nil, err
+		}
+
+		var calData calendarDataResp
+		if err := resp.DecodeProp(&calData); err != nil {
+			return nil, err
+		}
+
+		var getLastMod internal.GetLastModified
+		if err := resp.DecodeProp(&getLastMod); err != nil && !internal.IsNotFound(err) {
+			return nil, err
+		}
+
+		var getETag internal.GetETag
+		if err := resp.DecodeProp(&getETag); err != nil && !internal.IsNotFound(err) {
+			return nil, err
+		}
+		etag, err := strconv.Unquote(getETag.ETag)
+		if err != nil {
+			return nil, fmt.Errorf("carddav: failed to unquote ETag: %v", err)
+		}
+
+		addrs = append(addrs, CalendarObject{
+			Path:    path,
+			ModTime: time.Time(getLastMod.LastModified),
+			ETag:    etag,
+			Data:    calData.Data,
+		})
+	}
+
+	return addrs, nil
+}
+
+func (c *Client) QueryCalendar(calendar string, query *CalendarQuery) ([]CalendarObject, error) {
+	propReq, err := encodeCalendarReq(&query.Comp)
+	if err != nil {
+		return nil, err
+	}
+
+	calendarQuery := calendarQuery{Prop: propReq}
+	req, err := c.ic.NewXMLRequest("REPORT", calendar, &calendarQuery)
+	if err != nil {
+		return nil, err
+	}
+
+	ms, err := c.ic.DoMultiStatus(req)
+	if err != nil {
+		return nil, err
+	}
+
+	return decodeCalendarObjectList(ms)
+}

caldav/elements.go

@@ -85,7 +85,7 @@ type prop struct {
 }
 
 // Response variant of https://tools.ietf.org/html/rfc4791#section-9.6
-type calendarData struct {
+type calendarDataResp struct {
 	XMLName xml.Name `xml:"urn:ietf:params:xml:ns:caldav calendar-data"`
 	Data    []byte   `xml:",chardata"`
 }

internal/server.go

@@ -109,6 +109,7 @@ func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 				if href != nil {
 					w.Header().Set("Location", (*url.URL)(href).String())
 				}
+				// TODO: http.StatusNoContent if the resource already existed
 				w.WriteHeader(http.StatusCreated)
 			}
 		case http.MethodDelete: