go-webdav/internal/elements.go
Sebastien Binet 7d337ac048 internal: fix always-true interface comparison
This CL corrects the following bug uncovered by staticcheck:

```
  internal/elements.go:148:6: this comparison is always true (SA4023)
    internal/elements.go:146:18: the lhs of the comparison gets its value from here and has a concrete type
```

Signed-off-by: Sebastien Binet <binet@cern.ch>
2023-12-15 15:07:59 +01:00

453 lines
10 KiB
Go

package internal
import (
"encoding/xml"
"errors"
"fmt"
"net/http"
"net/url"
"strconv"
"strings"
"time"
)
const Namespace = "DAV:"
var (
ResourceTypeName = xml.Name{Namespace, "resourcetype"}
DisplayNameName = xml.Name{Namespace, "displayname"}
GetContentLengthName = xml.Name{Namespace, "getcontentlength"}
GetContentTypeName = xml.Name{Namespace, "getcontenttype"}
GetLastModifiedName = xml.Name{Namespace, "getlastmodified"}
GetETagName = xml.Name{Namespace, "getetag"}
CurrentUserPrincipalName = xml.Name{Namespace, "current-user-principal"}
)
type Status struct {
Code int
Text string
}
func (s *Status) MarshalText() ([]byte, error) {
text := s.Text
if text == "" {
text = http.StatusText(s.Code)
}
return []byte(fmt.Sprintf("HTTP/1.1 %v %v", s.Code, text)), nil
}
func (s *Status) UnmarshalText(b []byte) error {
if len(b) == 0 {
return nil
}
parts := strings.SplitN(string(b), " ", 3)
if len(parts) != 3 {
return fmt.Errorf("webdav: invalid HTTP status %q: expected 3 fields", s)
}
code, err := strconv.Atoi(parts[1])
if err != nil {
return fmt.Errorf("webdav: invalid HTTP status %q: failed to parse code: %v", s, err)
}
s.Code = code
s.Text = parts[2]
return nil
}
func (s *Status) Err() error {
if s == nil {
return nil
}
// TODO: handle 2xx, 3xx
if s.Code != http.StatusOK {
return &HTTPError{Code: s.Code}
}
return nil
}
type Href url.URL
func (h *Href) String() string {
u := (*url.URL)(h)
return u.String()
}
func (h *Href) MarshalText() ([]byte, error) {
return []byte(h.String()), nil
}
func (h *Href) UnmarshalText(b []byte) error {
u, err := url.Parse(string(b))
if err != nil {
return err
}
*h = Href(*u)
return nil
}
// https://tools.ietf.org/html/rfc4918#section-14.16
type MultiStatus struct {
XMLName xml.Name `xml:"DAV: multistatus"`
Responses []Response `xml:"response"`
ResponseDescription string `xml:"responsedescription,omitempty"`
SyncToken string `xml:"sync-token,omitempty"`
}
func NewMultiStatus(resps ...Response) *MultiStatus {
return &MultiStatus{Responses: resps}
}
// https://tools.ietf.org/html/rfc4918#section-14.24
type Response struct {
XMLName xml.Name `xml:"DAV: response"`
Hrefs []Href `xml:"href"`
PropStats []PropStat `xml:"propstat,omitempty"`
ResponseDescription string `xml:"responsedescription,omitempty"`
Status *Status `xml:"status,omitempty"`
Error *Error `xml:"error,omitempty"`
Location *Location `xml:"location,omitempty"`
}
func NewOKResponse(path string) *Response {
href := Href{Path: path}
return &Response{
Hrefs: []Href{href},
Status: &Status{Code: http.StatusOK},
}
}
func NewErrorResponse(path string, err error) *Response {
code := http.StatusInternalServerError
var httpErr *HTTPError
if errors.As(err, &httpErr) {
code = httpErr.Code
}
var errElt *Error
errors.As(err, &errElt)
href := Href{Path: path}
return &Response{
Hrefs: []Href{href},
Status: &Status{Code: code},
ResponseDescription: err.Error(),
Error: errElt,
}
}
func (resp *Response) Err() error {
if resp.Status == nil || resp.Status.Code/100 == 2 {
return nil
}
var err error
if resp.Error != nil {
err = resp.Error
}
if resp.ResponseDescription != "" {
if err != nil {
err = fmt.Errorf("%v (%w)", resp.ResponseDescription, err)
} else {
err = fmt.Errorf("%v", resp.ResponseDescription)
}
}
return &HTTPError{
Code: resp.Status.Code,
Err: err,
}
}
func (resp *Response) Path() (string, error) {
err := resp.Err()
var path string
if len(resp.Hrefs) == 1 {
path = resp.Hrefs[0].Path
} else if err == nil {
err = fmt.Errorf("webdav: malformed response: expected exactly one href element, got %v", len(resp.Hrefs))
}
return path, err
}
func (resp *Response) DecodeProp(values ...interface{}) error {
for _, v := range values {
// TODO wrap errors with more context (XML name)
name, err := valueXMLName(v)
if err != nil {
return err
}
if err := resp.Err(); err != nil {
return newPropError(name, err)
}
for _, propstat := range resp.PropStats {
raw := propstat.Prop.Get(name)
if raw == nil {
continue
}
if err := propstat.Status.Err(); err != nil {
return newPropError(name, err)
}
if err := raw.Decode(v); err != nil {
return newPropError(name, err)
}
return nil
}
return newPropError(name, &HTTPError{
Code: http.StatusNotFound,
Err: fmt.Errorf("missing property"),
})
}
return nil
}
func newPropError(name xml.Name, err error) error {
return fmt.Errorf("property <%v %v>: %w", name.Space, name.Local, err)
}
func (resp *Response) EncodeProp(code int, v interface{}) error {
raw, err := EncodeRawXMLElement(v)
if err != nil {
return err
}
for i := range resp.PropStats {
propstat := &resp.PropStats[i]
if propstat.Status.Code == code {
propstat.Prop.Raw = append(propstat.Prop.Raw, *raw)
return nil
}
}
resp.PropStats = append(resp.PropStats, PropStat{
Status: Status{Code: code},
Prop: Prop{Raw: []RawXMLValue{*raw}},
})
return nil
}
// https://tools.ietf.org/html/rfc4918#section-14.9
type Location struct {
XMLName xml.Name `xml:"DAV: location"`
Href Href `xml:"href"`
}
// https://tools.ietf.org/html/rfc4918#section-14.22
type PropStat struct {
XMLName xml.Name `xml:"DAV: propstat"`
Prop Prop `xml:"prop"`
Status Status `xml:"status"`
ResponseDescription string `xml:"responsedescription,omitempty"`
Error *Error `xml:"error,omitempty"`
}
// https://tools.ietf.org/html/rfc4918#section-14.18
type Prop struct {
XMLName xml.Name `xml:"DAV: prop"`
Raw []RawXMLValue `xml:",any"`
}
func EncodeProp(values ...interface{}) (*Prop, error) {
l := make([]RawXMLValue, len(values))
for i, v := range values {
raw, err := EncodeRawXMLElement(v)
if err != nil {
return nil, err
}
l[i] = *raw
}
return &Prop{Raw: l}, nil
}
func (p *Prop) Get(name xml.Name) *RawXMLValue {
for i := range p.Raw {
raw := &p.Raw[i]
if n, ok := raw.XMLName(); ok && name == n {
return raw
}
}
return nil
}
func (p *Prop) Decode(v interface{}) error {
name, err := valueXMLName(v)
if err != nil {
return err
}
raw := p.Get(name)
if raw == nil {
return HTTPErrorf(http.StatusNotFound, "missing property %s", name)
}
return raw.Decode(v)
}
// https://tools.ietf.org/html/rfc4918#section-14.20
type PropFind struct {
XMLName xml.Name `xml:"DAV: propfind"`
Prop *Prop `xml:"prop,omitempty"`
AllProp *struct{} `xml:"allprop,omitempty"`
Include *Include `xml:"include,omitempty"`
PropName *struct{} `xml:"propname,omitempty"`
}
func xmlNamesToRaw(names []xml.Name) []RawXMLValue {
l := make([]RawXMLValue, len(names))
for i, name := range names {
l[i] = *NewRawXMLElement(name, nil, nil)
}
return l
}
func NewPropNamePropFind(names ...xml.Name) *PropFind {
return &PropFind{Prop: &Prop{Raw: xmlNamesToRaw(names)}}
}
// https://tools.ietf.org/html/rfc4918#section-14.8
type Include struct {
XMLName xml.Name `xml:"DAV: include"`
Raw []RawXMLValue `xml:",any"`
}
// https://tools.ietf.org/html/rfc4918#section-15.9
type ResourceType struct {
XMLName xml.Name `xml:"DAV: resourcetype"`
Raw []RawXMLValue `xml:",any"`
}
func NewResourceType(names ...xml.Name) *ResourceType {
return &ResourceType{Raw: xmlNamesToRaw(names)}
}
func (t *ResourceType) Is(name xml.Name) bool {
for _, raw := range t.Raw {
if n, ok := raw.XMLName(); ok && name == n {
return true
}
}
return false
}
var CollectionName = xml.Name{Namespace, "collection"}
// https://tools.ietf.org/html/rfc4918#section-15.4
type GetContentLength struct {
XMLName xml.Name `xml:"DAV: getcontentlength"`
Length int64 `xml:",chardata"`
}
// https://tools.ietf.org/html/rfc4918#section-15.5
type GetContentType struct {
XMLName xml.Name `xml:"DAV: getcontenttype"`
Type string `xml:",chardata"`
}
type Time time.Time
func (t *Time) UnmarshalText(b []byte) error {
tt, err := http.ParseTime(string(b))
if err != nil {
return err
}
*t = Time(tt)
return nil
}
func (t *Time) MarshalText() ([]byte, error) {
s := time.Time(*t).UTC().Format(http.TimeFormat)
return []byte(s), nil
}
// https://tools.ietf.org/html/rfc4918#section-15.7
type GetLastModified struct {
XMLName xml.Name `xml:"DAV: getlastmodified"`
LastModified Time `xml:",chardata"`
}
// https://tools.ietf.org/html/rfc4918#section-15.6
type GetETag struct {
XMLName xml.Name `xml:"DAV: getetag"`
ETag ETag `xml:",chardata"`
}
type ETag string
func (etag *ETag) UnmarshalText(b []byte) error {
s, err := strconv.Unquote(string(b))
if err != nil {
return fmt.Errorf("webdav: failed to unquote ETag: %v", err)
}
*etag = ETag(s)
return nil
}
func (etag ETag) MarshalText() ([]byte, error) {
return []byte(etag.String()), nil
}
func (etag ETag) String() string {
return fmt.Sprintf("%q", string(etag))
}
// https://tools.ietf.org/html/rfc4918#section-14.5
type Error struct {
XMLName xml.Name `xml:"DAV: error"`
Raw []RawXMLValue `xml:",any"`
}
func (err *Error) Error() string {
b, _ := xml.Marshal(err)
return string(b)
}
// https://tools.ietf.org/html/rfc4918#section-15.2
type DisplayName struct {
XMLName xml.Name `xml:"DAV: displayname"`
Name string `xml:",chardata"`
}
// https://tools.ietf.org/html/rfc5397#section-3
type CurrentUserPrincipal struct {
XMLName xml.Name `xml:"DAV: current-user-principal"`
Href Href `xml:"href,omitempty"`
Unauthenticated *struct{} `xml:"unauthenticated,omitempty"`
}
// https://tools.ietf.org/html/rfc4918#section-14.19
type PropertyUpdate struct {
XMLName xml.Name `xml:"DAV: propertyupdate"`
Remove []Remove `xml:"remove"`
Set []Set `xml:"set"`
}
// https://tools.ietf.org/html/rfc4918#section-14.23
type Remove struct {
XMLName xml.Name `xml:"DAV: remove"`
Prop Prop `xml:"prop"`
}
// https://tools.ietf.org/html/rfc4918#section-14.26
type Set struct {
XMLName xml.Name `xml:"DAV: set"`
Prop Prop `xml:"prop"`
}
// https://tools.ietf.org/html/rfc6578#section-6.1
type SyncCollectionQuery struct {
XMLName xml.Name `xml:"DAV: sync-collection"`
SyncToken string `xml:"sync-token"`
Limit *Limit `xml:"limit,omitempty"`
SyncLevel string `xml:"sync-level"`
Prop *Prop `xml:"prop"`
}
// https://tools.ietf.org/html/rfc5323#section-5.17
type Limit struct {
XMLName xml.Name `xml:"DAV: limit"`
NResults uint `xml:"nresults"`
}