go-webdav/caldav/server.go
Conrad Hoffmann 6401d9ed45 caldav: extend query filter types
The basic types related to queries and filtering are missing some
features specified in the RFC (as also noted in the TODO comments). This
adds several of the missing elements, working towards being able to
handle all RFC-compliant queries.

The work is not fully done, e.g. the collation for text-match is still
not handled, but it's getting pretty close.
2022-04-01 18:29:58 +02:00

341 lines
9.8 KiB
Go

package caldav
import (
"context"
"encoding/xml"
"fmt"
"net/http"
"time"
"github.com/emersion/go-ical"
"github.com/emersion/go-webdav/internal"
)
// TODO: add support for multiple calendars
// Backend is a CalDAV server backend.
type Backend interface {
Calendar(ctx context.Context) (*Calendar, error)
GetCalendarObject(ctx context.Context, path string, req *CalendarCompRequest) (*CalendarObject, error)
ListCalendarObjects(ctx context.Context, req *CalendarCompRequest) ([]CalendarObject, error)
QueryCalendarObjects(ctx context.Context, query *CalendarQuery) ([]CalendarObject, error)
}
// Handler handles CalDAV HTTP requests. It can be used to create a CalDAV
// server.
type Handler struct {
Backend Backend
}
// ServeHTTP implements http.Handler.
func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
if h.Backend == nil {
http.Error(w, "caldav: no backend available", http.StatusInternalServerError)
return
}
if r.URL.Path == "/.well-known/caldav" {
http.Redirect(w, r, "/", http.StatusMovedPermanently)
return
}
var err error
switch r.Method {
case "REPORT":
err = h.handleReport(w, r)
default:
b := backend{h.Backend}
hh := internal.Handler{&b}
hh.ServeHTTP(w, r)
}
if err != nil {
internal.ServeError(w, err)
}
}
func (h *Handler) handleReport(w http.ResponseWriter, r *http.Request) error {
var report reportReq
if err := internal.DecodeXMLRequest(r, &report); err != nil {
return err
}
if report.Query != nil {
return h.handleQuery(r, w, report.Query)
} else if report.Multiget != nil {
return h.handleMultiget(w, report.Multiget)
}
return internal.HTTPErrorf(http.StatusBadRequest, "caldav: expected calendar-query or calendar-multiget element in REPORT request")
}
func decodeParamFilter(el *paramFilter) (*ParamFilter, error) {
pf := &ParamFilter{Name: el.Name}
if el.IsNotDefined != nil {
if el.TextMatch != nil {
return nil, fmt.Errorf("caldav: failed to parse param-filter: if is-not-defined is provided, text-match can't be provided")
}
pf.IsNotDefined = true
}
if el.TextMatch != nil {
pf.TextMatch = &TextMatch{Text: el.TextMatch.Text}
}
return pf, nil
}
func decodePropFilter(el *propFilter) (*PropFilter, error) {
pf := &PropFilter{Name: el.Name}
if el.IsNotDefined != nil {
if el.TextMatch != nil || el.TimeRange != nil || len(el.ParamFilter) > 0 {
return nil, fmt.Errorf("caldav: failed to parse prop-filter: if is-not-defined is provided, text-match, time-range, or param-filter can't be provided")
}
pf.IsNotDefined = true
}
if el.TextMatch != nil {
pf.TextMatch = &TextMatch{Text: el.TextMatch.Text}
}
if el.TimeRange != nil {
pf.Start = time.Time(el.TimeRange.Start)
pf.End = time.Time(el.TimeRange.End)
}
for _, paramEl := range el.ParamFilter {
paramFi, err := decodeParamFilter(&paramEl)
if err != nil {
return nil, err
}
pf.ParamFilter = append(pf.ParamFilter, *paramFi)
}
return pf, nil
}
func decodeCompFilter(el *compFilter) (*CompFilter, error) {
cf := &CompFilter{Name: el.Name}
if el.IsNotDefined != nil {
if el.TimeRange != nil || len(el.PropFilters) > 0 || len(el.CompFilters) > 0 {
return nil, fmt.Errorf("caldav: failed to parse comp-filter: if is-not-defined is provided, time-range, prop-filter, or comp-filter can't be provided")
}
cf.IsNotDefined = true
}
if el.TimeRange != nil {
cf.Start = time.Time(el.TimeRange.Start)
cf.End = time.Time(el.TimeRange.End)
}
for _, pfEl := range el.PropFilters {
pf, err := decodePropFilter(&pfEl)
if err != nil {
return nil, err
}
cf.Props = append(cf.Props, *pf)
}
for _, childEl := range el.CompFilters {
child, err := decodeCompFilter(&childEl)
if err != nil {
return nil, err
}
cf.Comps = append(cf.Comps, *child)
}
return cf, nil
}
func (h *Handler) handleQuery(r *http.Request, w http.ResponseWriter, query *calendarQuery) error {
var q CalendarQuery
// TODO: calendar-data in query.Prop
cf, err := decodeCompFilter(&query.Filter.CompFilter)
if err != nil {
return err
}
q.CompFilter = *cf
cos, err := h.Backend.QueryCalendarObjects(r.Context(), &q)
if err != nil {
return err
}
var resps []internal.Response
for _, co := range cos {
b := backend{h.Backend}
propfind := internal.Propfind{
Prop: query.Prop,
AllProp: query.AllProp,
PropName: query.PropName,
}
resp, err := b.propfindCalendarObject(&propfind, &co)
if err != nil {
return err
}
resps = append(resps, *resp)
}
ms := internal.NewMultistatus(resps...)
return internal.ServeMultistatus(w, ms)
}
func (h *Handler) handleMultiget(w http.ResponseWriter, multiget *calendarMultiget) error {
panic("TODO")
}
type backend struct {
Backend Backend
}
func (b *backend) Options(r *http.Request) (caps []string, allow []string, err error) {
caps = []string{"calendar-access"}
if r.URL.Path == "/" {
return caps, []string{http.MethodOptions, "PROPFIND", "REPORT"}, nil
}
var dataReq CalendarCompRequest
_, err = b.Backend.GetCalendarObject(r.Context(), r.URL.Path, &dataReq)
if httpErr, ok := err.(*internal.HTTPError); ok && httpErr.Code == http.StatusNotFound {
return caps, []string{http.MethodOptions, http.MethodPut}, nil
} else if err != nil {
return nil, nil, err
}
return caps, []string{
http.MethodOptions,
http.MethodHead,
http.MethodGet,
http.MethodPut,
http.MethodDelete,
"PROPFIND",
}, nil
}
func (b *backend) HeadGet(w http.ResponseWriter, r *http.Request) error {
panic("TODO")
}
func (b *backend) Propfind(r *http.Request, propfind *internal.Propfind, depth internal.Depth) (*internal.Multistatus, error) {
var resps []internal.Response
if r.URL.Path == "/" {
cal, err := b.Backend.Calendar(r.Context())
if err != nil {
return nil, err
}
resp, err := b.propfindCalendar(propfind, cal)
if err != nil {
return nil, err
}
resps = append(resps, *resp)
if depth != internal.DepthZero {
// TODO
}
}
return internal.NewMultistatus(resps...), nil
}
func (b *backend) propfindCalendar(propfind *internal.Propfind, cal *Calendar) (*internal.Response, error) {
props := map[xml.Name]internal.PropfindFunc{
internal.ResourceTypeName: func(*internal.RawXMLValue) (interface{}, error) {
return internal.NewResourceType(internal.CollectionName, calendarName), nil
},
internal.DisplayNameName: func(*internal.RawXMLValue) (interface{}, error) {
return &internal.DisplayName{Name: cal.Name}, nil
},
supportedCalendarDataName: func(*internal.RawXMLValue) (interface{}, error) {
return &supportedCalendarData{
Types: []calendarDataType{
{ContentType: ical.MIMEType, Version: "2.0"},
},
}, nil
},
supportedCalendarComponentSetName: func(*internal.RawXMLValue) (interface{}, error) {
return &supportedCalendarComponentSet{
Comp: []comp{
{Name: ical.CompEvent},
},
}, nil
},
// TODO: this is a principal property
calendarHomeSetName: func(*internal.RawXMLValue) (interface{}, error) {
return &calendarHomeSet{Href: internal.Href{Path: "/"}}, nil
},
// TODO: this should be set on all resources
internal.CurrentUserPrincipalName: func(*internal.RawXMLValue) (interface{}, error) {
return &internal.CurrentUserPrincipal{Href: internal.Href{Path: "/"}}, nil
},
}
if cal.Description != "" {
props[calendarDescriptionName] = func(*internal.RawXMLValue) (interface{}, error) {
return &calendarDescription{Description: cal.Description}, nil
}
}
if cal.MaxResourceSize > 0 {
props[maxResourceSizeName] = func(*internal.RawXMLValue) (interface{}, error) {
return &maxResourceSize{Size: cal.MaxResourceSize}, nil
}
}
// TODO: CALDAV:calendar-timezone, CALDAV:supported-calendar-component-set, CALDAV:min-date-time, CALDAV:max-date-time, CALDAV:max-instances, CALDAV:max-attendees-per-instance
return internal.NewPropfindResponse("/", propfind, props)
}
func (b *backend) propfindCalendarObject(propfind *internal.Propfind, co *CalendarObject) (*internal.Response, error) {
panic("TODO")
}
func (b *backend) Proppatch(r *http.Request, update *internal.Propertyupdate) (*internal.Response, error) {
panic("TODO")
}
func (b *backend) Put(r *http.Request) (*internal.Href, error) {
panic("TODO")
}
func (b *backend) Delete(r *http.Request) error {
panic("TODO")
}
func (b *backend) Mkcol(r *http.Request) error {
panic("TODO")
}
func (b *backend) Copy(r *http.Request, dest *internal.Href, recursive, overwrite bool) (created bool, err error) {
panic("TODO")
}
func (b *backend) Move(r *http.Request, dest *internal.Href, overwrite bool) (created bool, err error) {
panic("TODO")
}
// https://datatracker.ietf.org/doc/html/rfc4791#section-5.3.2.1
type PreconditionType string
const (
PreconditionNoUIDConflict PreconditionType = "no-uid-conflict"
PreconditionSupportedCalendarData PreconditionType = "supported-calendar-data"
PreconditionSupportedCalendarComponent PreconditionType = "supported-calendar-component"
PreconditionValidCalendarData PreconditionType = "valid-calendar-data"
PreconditionValidCalendarObjectResource PreconditionType = "valid-calendar-object-resource"
PreconditionCalendarCollectionLocationOk PreconditionType = "calendar-collection-location-ok"
PreconditionMaxResourceSize PreconditionType = "max-resource-size"
PreconditionMinDateTime PreconditionType = "min-date-time"
PreconditionMaxDateTime PreconditionType = "max-date-time"
PreconditionMaxInstances PreconditionType = "max-instances"
PreconditionMaxAttendeesPerInstance PreconditionType = "max-attendees-per-instance"
)
func NewPreconditionError(err PreconditionType) error {
name := xml.Name{"urn:ietf:params:xml:ns:caldav", string(err)}
elem := internal.NewRawXMLElement(name, nil, nil)
e := internal.Error{
Raw: []internal.RawXMLValue{
*elem,
},
}
return &internal.DAVError{
Code: 409,
Msg: fmt.Sprintf("precondition not met: %s", string(err)),
Err: e,
}
}