matrix-go-test/vendor/maunium.net/go/mautrix/id/matrixuri.go
2023-02-08 18:23:21 +01:00

293 lines
8.8 KiB
Go

// Copyright (c) 2021 Tulir Asokan
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
package id
import (
"errors"
"fmt"
"net/url"
"strings"
)
// Errors that can happen when parsing matrix: URIs
var (
ErrInvalidScheme = errors.New("matrix URI scheme must be exactly 'matrix'")
ErrInvalidPartCount = errors.New("matrix URIs must have exactly 2 or 4 segments")
ErrInvalidFirstSegment = errors.New("invalid identifier in first segment of matrix URI")
ErrEmptySecondSegment = errors.New("the second segment of the matrix URI must not be empty")
ErrInvalidThirdSegment = errors.New("invalid identifier in third segment of matrix URI")
ErrEmptyFourthSegment = errors.New("the fourth segment of the matrix URI must not be empty when the third segment is present")
)
// Errors that can happen when parsing matrix.to URLs
var (
ErrNotMatrixTo = errors.New("that URL is not a matrix.to URL")
ErrInvalidMatrixToPartCount = errors.New("matrix.to URLs must have exactly 1 or 2 segments")
ErrEmptyMatrixToPrimaryIdentifier = errors.New("the primary identifier in the matrix.to URL is empty")
ErrInvalidMatrixToPrimaryIdentifier = errors.New("the primary identifier in the matrix.to URL has an invalid sigil")
ErrInvalidMatrixToSecondaryIdentifier = errors.New("the secondary identifier in the matrix.to URL has an invalid sigil")
)
var ErrNotMatrixToOrMatrixURI = errors.New("that URL is not a matrix.to URL nor matrix: URI")
// MatrixURI contains the result of parsing a matrix: URI using ParseMatrixURI
type MatrixURI struct {
Sigil1 rune
Sigil2 rune
MXID1 string
MXID2 string
Via []string
Action string
}
// SigilToPathSegment contains a mapping from Matrix identifier sigils to matrix: URI path segments.
var SigilToPathSegment = map[rune]string{
'$': "e",
'#': "r",
'!': "roomid",
'@': "u",
}
func (uri *MatrixURI) getQuery() url.Values {
q := make(url.Values)
if uri.Via != nil && len(uri.Via) > 0 {
q["via"] = uri.Via
}
if len(uri.Action) > 0 {
q.Set("action", uri.Action)
}
return q
}
// String converts the parsed matrix: URI back into the string representation.
func (uri *MatrixURI) String() string {
parts := []string{
SigilToPathSegment[uri.Sigil1],
uri.MXID1,
}
if uri.Sigil2 != 0 {
parts = append(parts, SigilToPathSegment[uri.Sigil2], uri.MXID2)
}
return (&url.URL{
Scheme: "matrix",
Opaque: strings.Join(parts, "/"),
RawQuery: uri.getQuery().Encode(),
}).String()
}
// MatrixToURL converts to parsed matrix: URI into a matrix.to URL
func (uri *MatrixURI) MatrixToURL() string {
fragment := fmt.Sprintf("#/%s", url.QueryEscape(uri.PrimaryIdentifier()))
if uri.Sigil2 != 0 {
fragment = fmt.Sprintf("%s/%s", fragment, url.QueryEscape(uri.SecondaryIdentifier()))
}
query := uri.getQuery().Encode()
if len(query) > 0 {
fragment = fmt.Sprintf("%s?%s", fragment, query)
}
// It would be nice to use URL{...}.String() here, but figuring out the Fragment vs RawFragment stuff is a pain
return fmt.Sprintf("https://matrix.to/%s", fragment)
}
// PrimaryIdentifier returns the first Matrix identifier in the URI.
// Currently room IDs, room aliases and user IDs can be in the primary identifier slot.
func (uri *MatrixURI) PrimaryIdentifier() string {
return fmt.Sprintf("%c%s", uri.Sigil1, uri.MXID1)
}
// SecondaryIdentifier returns the second Matrix identifier in the URI.
// Currently only event IDs can be in the secondary identifier slot.
func (uri *MatrixURI) SecondaryIdentifier() string {
if uri.Sigil2 == 0 {
return ""
}
return fmt.Sprintf("%c%s", uri.Sigil2, uri.MXID2)
}
// UserID returns the user ID from the URI if the primary identifier is a user ID.
func (uri *MatrixURI) UserID() UserID {
if uri.Sigil1 == '@' {
return UserID(uri.PrimaryIdentifier())
}
return ""
}
// RoomID returns the room ID from the URI if the primary identifier is a room ID.
func (uri *MatrixURI) RoomID() RoomID {
if uri.Sigil1 == '!' {
return RoomID(uri.PrimaryIdentifier())
}
return ""
}
// RoomAlias returns the room alias from the URI if the primary identifier is a room alias.
func (uri *MatrixURI) RoomAlias() RoomAlias {
if uri.Sigil1 == '#' {
return RoomAlias(uri.PrimaryIdentifier())
}
return ""
}
// EventID returns the event ID from the URI if the primary identifier is a room ID or alias and the secondary identifier is an event ID.
func (uri *MatrixURI) EventID() EventID {
if (uri.Sigil1 == '!' || uri.Sigil1 == '#') && uri.Sigil2 == '$' {
return EventID(uri.SecondaryIdentifier())
}
return ""
}
// ParseMatrixURIOrMatrixToURL parses the given matrix.to URL or matrix: URI into a unified representation.
func ParseMatrixURIOrMatrixToURL(uri string) (*MatrixURI, error) {
parsed, err := url.Parse(uri)
if err != nil {
return nil, fmt.Errorf("failed to parse URI: %w", err)
}
if parsed.Scheme == "matrix" {
return ProcessMatrixURI(parsed)
} else if strings.HasSuffix(parsed.Hostname(), "matrix.to") {
return ProcessMatrixToURL(parsed)
} else {
return nil, ErrNotMatrixToOrMatrixURI
}
}
// ParseMatrixURI implements the matrix: URI parsing algorithm.
//
// Currently specified in https://github.com/matrix-org/matrix-doc/blob/master/proposals/2312-matrix-uri.md#uri-parsing-algorithm
func ParseMatrixURI(uri string) (*MatrixURI, error) {
// Step 1: parse the URI according to RFC 3986
parsed, err := url.Parse(uri)
if err != nil {
return nil, fmt.Errorf("failed to parse URI: %w", err)
}
return ProcessMatrixURI(parsed)
}
// ProcessMatrixURI implements steps 2-7 of the matrix: URI parsing algorithm
// (i.e. everything except parsing the URI itself, which is done with url.Parse or ParseMatrixURI)
func ProcessMatrixURI(uri *url.URL) (*MatrixURI, error) {
// Step 2: check that scheme is exactly `matrix`
if uri.Scheme != "matrix" {
return nil, ErrInvalidScheme
}
// Step 3: split the path into segments separated by /
parts := strings.Split(uri.Opaque, "/")
// Step 4: Check that the URI contains either 2 or 4 segments
if len(parts) != 2 && len(parts) != 4 {
return nil, ErrInvalidPartCount
}
var parsed MatrixURI
// Step 5: Construct the top-level Matrix identifier
// a: find the sigil from the first segment
switch parts[0] {
case "u", "user":
parsed.Sigil1 = '@'
case "r", "room":
parsed.Sigil1 = '#'
case "roomid":
parsed.Sigil1 = '!'
default:
return nil, fmt.Errorf("%w: '%s'", ErrInvalidFirstSegment, parts[0])
}
// b: find the identifier from the second segment
if len(parts[1]) == 0 {
return nil, ErrEmptySecondSegment
}
parsed.MXID1 = parts[1]
// Step 6: if the first part is a room and the URI has 4 segments, construct a second level identifier
if (parsed.Sigil1 == '!' || parsed.Sigil1 == '#') && len(parts) == 4 {
// a: find the sigil from the third segment
switch parts[2] {
case "e", "event":
parsed.Sigil2 = '$'
default:
return nil, fmt.Errorf("%w: '%s'", ErrInvalidThirdSegment, parts[0])
}
// b: find the identifier from the fourth segment
if len(parts[3]) == 0 {
return nil, ErrEmptyFourthSegment
}
parsed.MXID2 = parts[3]
}
// Step 7: parse the query and extract via and action items
via, ok := uri.Query()["via"]
if ok && len(via) > 0 {
parsed.Via = via
}
action, ok := uri.Query()["action"]
if ok && len(action) > 0 {
parsed.Action = action[len(action)-1]
}
return &parsed, nil
}
// ParseMatrixToURL parses a matrix.to URL into the same container as ParseMatrixURI parses matrix: URIs.
func ParseMatrixToURL(uri string) (*MatrixURI, error) {
parsed, err := url.Parse(uri)
if err != nil {
return nil, fmt.Errorf("failed to parse URL: %w", err)
}
return ProcessMatrixToURL(parsed)
}
// ProcessMatrixToURL is the equivalent of ProcessMatrixURI for matrix.to URLs.
func ProcessMatrixToURL(uri *url.URL) (*MatrixURI, error) {
if !strings.HasSuffix(uri.Hostname(), "matrix.to") {
return nil, ErrNotMatrixTo
}
initialSplit := strings.SplitN(uri.Fragment, "?", 2)
parts := strings.Split(initialSplit[0], "/")
if len(initialSplit) > 1 {
uri.RawQuery = initialSplit[1]
}
if len(parts) < 2 || len(parts) > 3 {
return nil, ErrInvalidMatrixToPartCount
}
if len(parts[1]) == 0 {
return nil, ErrEmptyMatrixToPrimaryIdentifier
}
var parsed MatrixURI
parsed.Sigil1 = rune(parts[1][0])
parsed.MXID1 = parts[1][1:]
_, isKnown := SigilToPathSegment[parsed.Sigil1]
if !isKnown {
return nil, ErrInvalidMatrixToPrimaryIdentifier
}
if len(parts) == 3 && len(parts[2]) > 0 {
parsed.Sigil2 = rune(parts[2][0])
parsed.MXID2 = parts[2][1:]
_, isKnown = SigilToPathSegment[parsed.Sigil2]
if !isKnown {
return nil, ErrInvalidMatrixToSecondaryIdentifier
}
}
via, ok := uri.Query()["via"]
if ok && len(via) > 0 {
parsed.Via = via
}
action, ok := uri.Query()["action"]
if ok && len(action) > 0 {
parsed.Action = action[len(action)-1]
}
return &parsed, nil
}