gotosocial/internal/ap/extract.go

1457 lines
38 KiB
Go

// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package ap
import (
"crypto"
"crypto/rsa"
"crypto/x509"
"encoding/pem"
"errors"
"fmt"
"net/url"
"strings"
"time"
"github.com/superseriousbusiness/activity/pub"
"github.com/superseriousbusiness/activity/streams/vocab"
"github.com/superseriousbusiness/gotosocial/internal/gtserror"
"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
"github.com/superseriousbusiness/gotosocial/internal/text"
"github.com/superseriousbusiness/gotosocial/internal/util"
)
// ExtractObjects will extract object vocab.Types from given implementing interface.
func ExtractObjects(with WithObject) []TypeOrIRI {
// Extract the attached object (if any).
objProp := with.GetActivityStreamsObject()
if objProp == nil {
return nil
}
// Check for zero len.
if objProp.Len() == 0 {
return nil
}
// Accumulate all of the objects into a slice.
objs := make([]TypeOrIRI, objProp.Len())
for i := 0; i < objProp.Len(); i++ {
objs[i] = objProp.At(i)
}
return objs
}
// ExtractActivityData will extract the usable data type (e.g. Note, Question, etc) and corresponding JSON, from activity.
func ExtractActivityData(activity pub.Activity, rawJSON map[string]any) ([]TypeOrIRI, []any, bool) {
switch typeName := activity.GetTypeName(); {
// Activity (has "object").
case isActivity(typeName):
objTypes := ExtractObjects(activity)
if len(objTypes) == 0 {
return nil, nil, false
}
var objJSON []any
switch json := rawJSON["object"].(type) {
case nil:
// do nothing
case map[string]any:
// Wrap map in slice.
objJSON = []any{json}
case []any:
// Use existing slice.
objJSON = json
}
return objTypes, objJSON, true
// IntransitiveAcitivity (no "object").
case isIntransitiveActivity(typeName):
asTypeOrIRI := _TypeOrIRI{activity} // wrap activity.
return []TypeOrIRI{&asTypeOrIRI}, []any{rawJSON}, true
// Unknown.
default:
return nil, nil, false
}
}
// ExtractAccountables extracts Accountable objects from a slice TypeOrIRI, returning extracted and remaining TypeOrIRIs.
func ExtractAccountables(arr []TypeOrIRI) ([]Accountable, []TypeOrIRI) {
var accounts []Accountable
for i := 0; i < len(arr); i++ {
elem := arr[i]
if elem.IsIRI() {
// skip IRIs
continue
}
// Extract AS vocab type
// associated with elem.
t := elem.GetType()
// Try cast AS type as Accountable.
account, ok := ToAccountable(t)
if !ok {
continue
}
// Add casted accountable type.
accounts = append(accounts, account)
// Drop elem from slice.
copy(arr[:i], arr[i+1:])
arr = arr[:len(arr)-1]
}
return accounts, arr
}
// ExtractStatusables extracts Statusable objects from a slice TypeOrIRI, returning extracted and remaining TypeOrIRIs.
func ExtractStatusables(arr []TypeOrIRI) ([]Statusable, []TypeOrIRI) {
var statuses []Statusable
for i := 0; i < len(arr); i++ {
elem := arr[i]
if elem.IsIRI() {
// skip IRIs
continue
}
// Extract AS vocab type
// associated with elem.
t := elem.GetType()
// Try cast AS type as Statusable.
status, ok := ToStatusable(t)
if !ok {
continue
}
// Add casted Statusable type.
statuses = append(statuses, status)
// Drop elem from slice.
copy(arr[:i], arr[i+1:])
arr = arr[:len(arr)-1]
}
return statuses, arr
}
// ExtractPollOptionables extracts PollOptionable objects from a slice TypeOrIRI, returning extracted and remaining TypeOrIRIs.
func ExtractPollOptionables(arr []TypeOrIRI) ([]PollOptionable, []TypeOrIRI) {
var options []PollOptionable
for i := 0; i < len(arr); i++ {
elem := arr[i]
if elem.IsIRI() {
// skip IRIs
continue
}
// Extract AS vocab type
// associated with elem.
t := elem.GetType()
// Try cast as PollOptionable.
option, ok := ToPollOptionable(t)
if !ok {
continue
}
// Add casted PollOptionable type.
options = append(options, option)
// Drop elem from slice.
copy(arr[:i], arr[i+1:])
arr = arr[:len(arr)-1]
}
return options, arr
}
// ExtractPreferredUsername returns a string representation of
// an interface's preferredUsername property. Will return an
// error if preferredUsername is nil, not a string, or empty.
func ExtractPreferredUsername(i WithPreferredUsername) string {
u := i.GetActivityStreamsPreferredUsername()
if u == nil || !u.IsXMLSchemaString() {
return ""
}
return u.GetXMLSchemaString()
}
// ExtractName returns the first string representation it
// can find of an interface's name property, or an empty
// string if this is not found.
func ExtractName(i WithName) string {
nameProp := i.GetActivityStreamsName()
if nameProp == nil {
return ""
}
for iter := nameProp.Begin(); iter != nameProp.End(); iter = iter.Next() {
// Name may be parsed as IRI, depending on
// how it's formatted, so account for this.
switch {
case iter.IsXMLSchemaString():
return iter.GetXMLSchemaString()
case iter.IsIRI():
return iter.GetIRI().String()
}
}
return ""
}
// ExtractInReplyToURI extracts the first inReplyTo URI
// property it can find from an interface. Will return
// nil if no valid URI can be found.
func ExtractInReplyToURI(i WithInReplyTo) *url.URL {
inReplyToProp := i.GetActivityStreamsInReplyTo()
if inReplyToProp == nil {
return nil
}
for iter := inReplyToProp.Begin(); iter != inReplyToProp.End(); iter = iter.Next() {
iri, err := pub.ToId(iter)
if err == nil && iri != nil {
// Found one we can use.
return iri
}
}
return nil
}
// ExtractItemsURIs extracts each URI it can
// find for an item from the provided WithItems.
func ExtractItemsURIs(i WithItems) []*url.URL {
itemsProp := i.GetActivityStreamsItems()
if itemsProp == nil {
return nil
}
uris := make([]*url.URL, 0, itemsProp.Len())
for iter := itemsProp.Begin(); iter != itemsProp.End(); iter = iter.Next() {
uri, err := pub.ToId(iter)
if err == nil {
// Found one we can use.
uris = append(uris, uri)
}
}
return uris
}
// ExtractToURIs returns a slice of URIs
// that the given WithTo addresses as To.
func ExtractToURIs(i WithTo) []*url.URL {
toProp := i.GetActivityStreamsTo()
if toProp == nil {
return nil
}
uris := make([]*url.URL, 0, toProp.Len())
for iter := toProp.Begin(); iter != toProp.End(); iter = iter.Next() {
uri, err := pub.ToId(iter)
if err == nil {
// Found one we can use.
uris = append(uris, uri)
}
}
return uris
}
// ExtractCcURIs returns a slice of URIs
// that the given WithCC addresses as Cc.
func ExtractCcURIs(i WithCc) []*url.URL {
ccProp := i.GetActivityStreamsCc()
if ccProp == nil {
return nil
}
urls := make([]*url.URL, 0, ccProp.Len())
for iter := ccProp.Begin(); iter != ccProp.End(); iter = iter.Next() {
uri, err := pub.ToId(iter)
if err == nil {
// Found one we can use.
urls = append(urls, uri)
}
}
return urls
}
// ExtractAttributedToURI returns the first URI it can find in the
// given WithAttributedTo, or an error if no URI can be found.
func ExtractAttributedToURI(i WithAttributedTo) (*url.URL, error) {
attributedToProp := i.GetActivityStreamsAttributedTo()
if attributedToProp == nil {
return nil, gtserror.New("attributedToProp was nil")
}
for iter := attributedToProp.Begin(); iter != attributedToProp.End(); iter = iter.Next() {
id, err := pub.ToId(iter)
if err == nil {
return id, nil
}
}
return nil, gtserror.New("couldn't find iri for attributed to")
}
// ExtractIconURI extracts the first URI it can find from
// the given WithIcon which links to a supported image file.
// Input will look something like this:
//
// "icon": {
// "mediaType": "image/jpeg",
// "type": "Image",
// "url": "http://example.org/path/to/some/file.jpeg"
// },
//
// If no valid URI can be found, this will return an error.
func ExtractIconURI(i WithIcon) (*url.URL, error) {
iconProp := i.GetActivityStreamsIcon()
if iconProp == nil {
return nil, gtserror.New("icon property was nil")
}
// Icon can potentially contain multiple entries,
// so we iterate through all of them here in order
// to find the first one that meets these criteria:
//
// 1. Is an image.
// 2. Has a URL that we can use to derefereince it.
for iter := iconProp.Begin(); iter != iconProp.End(); iter = iter.Next() {
if !iter.IsActivityStreamsImage() {
continue
}
image := iter.GetActivityStreamsImage()
if image == nil {
continue
}
imageURL, err := ExtractURL(image)
if err == nil && imageURL != nil {
return imageURL, nil
}
}
return nil, gtserror.New("could not extract valid image URI from icon")
}
// ExtractImageURI extracts the first URI it can find from
// the given WithImage which links to a supported image file.
// Input will look something like this:
//
// "image": {
// "mediaType": "image/jpeg",
// "type": "Image",
// "url": "http://example.org/path/to/some/file.jpeg"
// },
//
// If no valid URI can be found, this will return an error.
func ExtractImageURI(i WithImage) (*url.URL, error) {
imageProp := i.GetActivityStreamsImage()
if imageProp == nil {
return nil, gtserror.New("image property was nil")
}
// Image can potentially contain multiple entries,
// so we iterate through all of them here in order
// to find the first one that meets these criteria:
//
// 1. Is an image.
// 2. Has a URL that we can use to derefereince it.
for iter := imageProp.Begin(); iter != imageProp.End(); iter = iter.Next() {
if !iter.IsActivityStreamsImage() {
continue
}
image := iter.GetActivityStreamsImage()
if image == nil {
continue
}
imageURL, err := ExtractURL(image)
if err == nil && imageURL != nil {
return imageURL, nil
}
}
return nil, gtserror.New("could not extract valid image URI from image")
}
// ExtractSummary extracts the summary/content warning of
// the given WithSummary interface. Will return an empty
// string if no summary/content warning was present.
func ExtractSummary(i WithSummary) string {
summaryProp := i.GetActivityStreamsSummary()
if summaryProp == nil {
return ""
}
for iter := summaryProp.Begin(); iter != summaryProp.End(); iter = iter.Next() {
// Summary may be parsed as IRI, depending on
// how it's formatted, so account for this.
switch {
case iter.IsXMLSchemaString():
return iter.GetXMLSchemaString()
case iter.IsIRI():
return iter.GetIRI().String()
}
}
return ""
}
// ExtractFields extracts property/value fields from the given
// WithAttachment interface. Will return an empty slice if no
// property/value fields can be found. Attachments that are not
// (well-formed) PropertyValues will be ignored.
func ExtractFields(i WithAttachment) []*gtsmodel.Field {
attachmentProp := i.GetActivityStreamsAttachment()
if attachmentProp == nil {
// Nothing to do.
return nil
}
l := attachmentProp.Len()
if l == 0 {
// Nothing to do.
return nil
}
fields := make([]*gtsmodel.Field, 0, l)
for iter := attachmentProp.Begin(); iter != attachmentProp.End(); iter = iter.Next() {
if !iter.IsSchemaPropertyValue() {
continue
}
propertyValue := iter.GetSchemaPropertyValue()
if propertyValue == nil {
continue
}
nameProp := propertyValue.GetActivityStreamsName()
if nameProp == nil || nameProp.Len() != 1 {
continue
}
name := nameProp.At(0).GetXMLSchemaString()
if name == "" {
continue
}
valueProp := propertyValue.GetSchemaValue()
if valueProp == nil || !valueProp.IsXMLSchemaString() {
continue
}
value := valueProp.Get()
if value == "" {
continue
}
fields = append(fields, &gtsmodel.Field{
Name: name,
Value: value,
})
}
return fields
}
// ExtractURL extracts the first URI it can find from the
// given WithURL interface, or an error if no URL was set.
// The ID of a type will not work, this function wants a URI
// specifically.
func ExtractURL(i WithURL) (*url.URL, error) {
urlProp := i.GetActivityStreamsUrl()
if urlProp == nil {
return nil, gtserror.New("url property was nil")
}
for iter := urlProp.Begin(); iter != urlProp.End(); iter = iter.Next() {
if !iter.IsIRI() {
continue
}
// Found it.
return iter.GetIRI(), nil
}
return nil, gtserror.New("no valid URL property found")
}
// ExtractPubKeyFromActor extracts the public key, public key ID, and public
// key owner ID from an interface, or an error if something goes wrong.
func ExtractPubKeyFromActor(i WithPublicKey) (
*rsa.PublicKey, // pubkey
*url.URL, // pubkey ID
*url.URL, // pubkey owner
error,
) {
pubKeyProp := i.GetW3IDSecurityV1PublicKey()
if pubKeyProp == nil {
return nil, nil, nil, gtserror.New("public key property was nil")
}
// Take the first public key we can find.
for iter := pubKeyProp.Begin(); iter != pubKeyProp.End(); iter = iter.Next() {
if !iter.IsW3IDSecurityV1PublicKey() {
continue
}
pkey := iter.Get()
if pkey == nil {
continue
}
return ExtractPubKeyFromKey(pkey)
}
return nil, nil, nil, gtserror.New("couldn't find valid public key")
}
// ExtractPubKeyFromActor extracts the public key, public key ID, and public
// key owner ID from an interface, or an error if something goes wrong.
func ExtractPubKeyFromKey(pkey vocab.W3IDSecurityV1PublicKey) (
*rsa.PublicKey, // pubkey
*url.URL, // pubkey ID
*url.URL, // pubkey owner
error,
) {
pubKeyID, err := pub.GetId(pkey)
if err != nil {
return nil, nil, nil, errors.New("no id set on public key")
}
pubKeyOwnerProp := pkey.GetW3IDSecurityV1Owner()
if pubKeyOwnerProp == nil {
return nil, nil, nil, errors.New("nil pubKeyOwnerProp")
}
pubKeyOwner := pubKeyOwnerProp.GetIRI()
if pubKeyOwner == nil {
return nil, nil, nil, errors.New("nil iri on pubKeyOwnerProp")
}
pubKeyPemProp := pkey.GetW3IDSecurityV1PublicKeyPem()
if pubKeyPemProp == nil {
return nil, nil, nil, errors.New("nil pubKeyPemProp")
}
pkeyPem := pubKeyPemProp.Get()
if pkeyPem == "" {
return nil, nil, nil, errors.New("empty pubKeyPemProp")
}
block, _ := pem.Decode([]byte(pkeyPem))
if block == nil {
return nil, nil, nil, errors.New("nil pubKeyPem")
}
var p crypto.PublicKey
switch block.Type {
case "PUBLIC KEY":
p, err = x509.ParsePKIXPublicKey(block.Bytes)
case "RSA PUBLIC KEY":
p, err = x509.ParsePKCS1PublicKey(block.Bytes)
default:
err = fmt.Errorf("unknown block type: %q", block.Type)
}
if err != nil {
err = fmt.Errorf("could not parse public key from block bytes: %w", err)
return nil, nil, nil, err
}
if p == nil {
return nil, nil, nil, fmt.Errorf("returned public key was empty")
}
pubKey, ok := p.(*rsa.PublicKey)
if !ok {
return nil, nil, nil, fmt.Errorf("could not type pubKey to *rsa.PublicKey")
}
return pubKey, pubKeyID, pubKeyOwner, nil
}
// ExtractContent returns an intermediary representation of
// the given interface's Content and/or ContentMap property.
func ExtractContent(i WithContent) gtsmodel.Content {
content := gtsmodel.Content{}
contentProp := i.GetActivityStreamsContent()
if contentProp == nil {
// No content at all.
return content
}
for iter := contentProp.Begin(); iter != contentProp.End(); iter = iter.Next() {
switch {
case iter.IsRDFLangString() &&
len(content.ContentMap) == 0:
content.ContentMap = iter.GetRDFLangString()
case iter.IsXMLSchemaString() &&
content.Content == "":
content.Content = iter.GetXMLSchemaString()
case iter.IsIRI() &&
content.Content == "":
content.Content = iter.GetIRI().String()
}
}
return content
}
// ExtractAttachments attempts to extract barebones MediaAttachment objects from given AS interface type.
func ExtractAttachments(i WithAttachment) ([]*gtsmodel.MediaAttachment, error) {
attachmentProp := i.GetActivityStreamsAttachment()
if attachmentProp == nil {
return nil, nil
}
var errs gtserror.MultiError
attachments := make([]*gtsmodel.MediaAttachment, 0, attachmentProp.Len())
for iter := attachmentProp.Begin(); iter != attachmentProp.End(); iter = iter.Next() {
t := iter.GetType()
if t == nil {
errs.Appendf("nil attachment type")
continue
}
attachmentable, ok := t.(Attachmentable)
if !ok {
errs.Appendf("incorrect attachment type: %T", t)
continue
}
attachment, err := ExtractAttachment(attachmentable)
if err != nil {
errs.Appendf("error extracting attachment: %w", err)
continue
}
attachments = append(attachments, attachment)
}
return attachments, errs.Combine()
}
// ExtractAttachment extracts a minimal gtsmodel.Attachment
// (just remote URL, description, and blurhash) from the given
// Attachmentable interface, or an error if no remote URL is set.
func ExtractAttachment(i Attachmentable) (*gtsmodel.MediaAttachment, error) {
// Get the URL for the attachment file.
// If no URL is set, we can't do anything.
remoteURL, err := ExtractURL(i)
if err != nil {
return nil, gtserror.Newf("error extracting attachment URL: %w", err)
}
return &gtsmodel.MediaAttachment{
RemoteURL: remoteURL.String(),
Description: ExtractDescription(i),
Blurhash: ExtractBlurhash(i),
Processing: gtsmodel.ProcessingStatusReceived,
}, nil
}
// ExtractDescription extracts the image description
// of an attachmentable, if present. Will try the
// 'summary' prop first, then fall back to 'name'.
func ExtractDescription(i Attachmentable) string {
if summary := ExtractSummary(i); summary != "" {
return summary
}
return ExtractName(i)
}
// ExtractBlurhash extracts the blurhash string value
// from the given WithBlurhash interface, or returns
// an empty string if nothing is found.
func ExtractBlurhash(i WithBlurhash) string {
blurhashProp := i.GetTootBlurhash()
if blurhashProp == nil {
return ""
}
return blurhashProp.Get()
}
// ExtractHashtags extracts a slice of minimal gtsmodel.Tags
// from a WithTag. If an entry in the WithTag is not a hashtag,
// or has a name that cannot be normalized, it will be ignored.
//
// TODO: find a better heuristic for determining if something
// is a hashtag or not, since looking for type name "Hashtag"
// is non-normative. Perhaps look for things that are either
// type "Hashtag" or have no type name set at all?
func ExtractHashtags(i WithTag) ([]*gtsmodel.Tag, error) {
tagsProp := i.GetActivityStreamsTag()
if tagsProp == nil {
return nil, nil
}
var (
l = tagsProp.Len()
tags = make([]*gtsmodel.Tag, 0, l)
keys = make(map[string]any, l) // Use map to dedupe items.
)
for iter := tagsProp.Begin(); iter != tagsProp.End(); iter = iter.Next() {
t := iter.GetType()
if t == nil {
continue
}
if t.GetTypeName() != TagHashtag {
continue
}
hashtaggable, ok := t.(Hashtaggable)
if !ok {
continue
}
tag, err := extractHashtag(hashtaggable)
if err != nil {
continue
}
// "Normalize" this tag by combining diacritics +
// unicode chars. If this returns false, it means
// we couldn't normalize it well enough to make it
// valid on our instance, so just ignore it.
normalized, ok := text.NormalizeHashtag(tag.Name)
if !ok {
continue
}
// We store tag names lowercased, might
// as well change case here already.
tag.Name = strings.ToLower(normalized)
// Only append this tag if we haven't
// seen it already, to avoid duplicates
// in the slice.
if _, set := keys[tag.Name]; !set {
keys[tag.Name] = nil // Value doesn't matter.
tags = append(tags, tag)
}
}
return tags, nil
}
// extractHashtag extracts a minimal gtsmodel.Tag from the given
// Hashtaggable, without yet doing any normalization on it.
func extractHashtag(i Hashtaggable) (*gtsmodel.Tag, error) {
// Extract name for the tag; trim leading hash
// character, so '#example' becomes 'example'.
name := ExtractName(i)
if name == "" {
return nil, gtserror.New("name prop empty")
}
tagName := strings.TrimPrefix(name, "#")
// Extract href for the tag, if set.
//
// Fine if not, it's only used for spam
// checking anyway so not critical.
var href string
hrefProp := i.GetActivityStreamsHref()
if hrefProp != nil && hrefProp.IsIRI() {
href = hrefProp.GetIRI().String()
}
return &gtsmodel.Tag{
Name: tagName,
Useable: util.Ptr(true), // Assume true by default.
Listable: util.Ptr(true), // Assume true by default.
Href: href,
}, nil
}
// ExtractEmojis extracts a slice of minimal gtsmodel.Emojis
// from a WithTag. If an entry in the WithTag is not an emoji,
// it will be quietly ignored.
func ExtractEmojis(i WithTag) ([]*gtsmodel.Emoji, error) {
tagsProp := i.GetActivityStreamsTag()
if tagsProp == nil {
return nil, nil
}
var (
l = tagsProp.Len()
emojis = make([]*gtsmodel.Emoji, 0, l)
keys = make(map[string]any, l) // Use map to dedupe items.
)
for iter := tagsProp.Begin(); iter != tagsProp.End(); iter = iter.Next() {
if !iter.IsTootEmoji() {
continue
}
tootEmoji := iter.GetTootEmoji()
if tootEmoji == nil {
continue
}
emoji, err := ExtractEmoji(tootEmoji)
if err != nil {
return nil, err
}
// Only append this emoji if we haven't
// seen it already, to avoid duplicates
// in the slice.
if _, set := keys[emoji.URI]; !set {
keys[emoji.URI] = nil // Value doesn't matter.
emojis = append(emojis, emoji)
}
}
return emojis, nil
}
// ExtractEmoji extracts a minimal gtsmodel.Emoji
// from the given Emojiable.
func ExtractEmoji(i Emojiable) (*gtsmodel.Emoji, error) {
// Use AP ID as emoji URI.
idProp := i.GetJSONLDId()
if idProp == nil || !idProp.IsIRI() {
return nil, gtserror.New("no id for emoji")
}
uri := idProp.GetIRI()
// Extract emoji last updated time (optional).
var updatedAt time.Time
updatedProp := i.GetActivityStreamsUpdated()
if updatedProp != nil && updatedProp.IsXMLSchemaDateTime() {
updatedAt = updatedProp.Get()
}
// Extract emoji name aka shortcode.
name := ExtractName(i)
if name == "" {
return nil, gtserror.New("name prop empty")
}
shortcode := strings.Trim(name, ":")
// Extract emoji image URL from Icon property.
imageRemoteURL, err := ExtractIconURI(i)
if err != nil {
return nil, gtserror.New("no url for emoji image")
}
imageRemoteURLStr := imageRemoteURL.String()
return &gtsmodel.Emoji{
UpdatedAt: updatedAt,
Shortcode: shortcode,
Domain: uri.Host,
ImageRemoteURL: imageRemoteURLStr,
URI: uri.String(),
Disabled: new(bool), // Assume false by default.
VisibleInPicker: new(bool), // Assume false by default.
}, nil
}
// ExtractMentions extracts a slice of minimal gtsmodel.Mentions
// from a WithTag. If an entry in the WithTag is not a mention,
// it will be quietly ignored.
func ExtractMentions(i WithTag) ([]*gtsmodel.Mention, error) {
tagsProp := i.GetActivityStreamsTag()
if tagsProp == nil {
return nil, nil
}
var (
l = tagsProp.Len()
mentions = make([]*gtsmodel.Mention, 0, l)
keys = make(map[string]any, l) // Use map to dedupe items.
)
for iter := tagsProp.Begin(); iter != tagsProp.End(); iter = iter.Next() {
if !iter.IsActivityStreamsMention() {
continue
}
asMention := iter.GetActivityStreamsMention()
if asMention == nil {
continue
}
mention, err := ExtractMention(asMention)
if err != nil {
return nil, err
}
// Only append this mention if we haven't
// seen it already, to avoid duplicates
// in the slice.
if _, set := keys[mention.TargetAccountURI]; !set {
keys[mention.TargetAccountURI] = nil // Value doesn't matter.
mentions = append(mentions, mention)
}
}
return mentions, nil
}
// ExtractMention extracts a minimal gtsmodel.Mention from a Mentionable.
func ExtractMention(i Mentionable) (*gtsmodel.Mention, error) {
// See if a name has been set in the
// format `@someone@example.org`.
nameString := ExtractName(i)
// The href prop should be the AP URI
// of the target account; it could also
// be the URL, but we'll check this later.
var href string
hrefProp := i.GetActivityStreamsHref()
if hrefProp != nil && hrefProp.IsIRI() {
href = hrefProp.GetIRI().String()
}
// One of nameString and hrefProp must be set.
if nameString == "" && href == "" {
return nil, gtserror.Newf("neither Name nor Href were set")
}
return &gtsmodel.Mention{
NameString: nameString,
TargetAccountURI: href,
}, nil
}
// ExtractActorURI extracts the first Actor URI
// it can find from a WithActor interface.
func ExtractActorURI(withActor WithActor) (*url.URL, error) {
actorProp := withActor.GetActivityStreamsActor()
if actorProp == nil {
return nil, gtserror.New("actor property was nil")
}
for iter := actorProp.Begin(); iter != actorProp.End(); iter = iter.Next() {
id, err := pub.ToId(iter)
if err == nil {
// Found one we can use.
return id, nil
}
}
return nil, gtserror.New("no iri found for actor prop")
}
// ExtractObjectURI extracts the first Object URI
// it can find from a WithObject interface.
func ExtractObjectURI(withObject WithObject) (*url.URL, error) {
objectProp := withObject.GetActivityStreamsObject()
if objectProp == nil {
return nil, gtserror.New("object property was nil")
}
for iter := objectProp.Begin(); iter != objectProp.End(); iter = iter.Next() {
id, err := pub.ToId(iter)
if err == nil {
// Found one we can use.
return id, nil
}
}
return nil, gtserror.New("no iri found for object prop")
}
// ExtractObjectURIs extracts the URLs of each Object
// it can find from a WithObject interface.
func ExtractObjectURIs(withObject WithObject) ([]*url.URL, error) {
objectProp := withObject.GetActivityStreamsObject()
if objectProp == nil {
return nil, gtserror.New("object property was nil")
}
urls := make([]*url.URL, 0, objectProp.Len())
for iter := objectProp.Begin(); iter != objectProp.End(); iter = iter.Next() {
id, err := pub.ToId(iter)
if err == nil {
// Found one we can use.
urls = append(urls, id)
}
}
return urls, nil
}
// ExtractVisibility extracts the gtsmodel.Visibility
// of a given addressable with a To and CC property.
//
// ActorFollowersURI is needed to check whether the
// visibility is FollowersOnly or not. The passed-in
// value should just be the string value representation
// of the followers URI of the actor who created the activity,
// eg., `https://example.org/users/whoever/followers`.
func ExtractVisibility(addressable Addressable, actorFollowersURI string) (gtsmodel.Visibility, error) {
var (
to = ExtractToURIs(addressable)
cc = ExtractCcURIs(addressable)
)
if len(to) == 0 && len(cc) == 0 {
return "", gtserror.Newf("message wasn't TO or CC anyone")
}
// Assume most restrictive visibility,
// and work our way up from there.
visibility := gtsmodel.VisibilityDirect
if isFollowers(to, actorFollowersURI) {
// Followers in TO: it's at least followers only.
visibility = gtsmodel.VisibilityFollowersOnly
}
if isPublic(cc) {
// CC'd to public: it's at least unlocked.
visibility = gtsmodel.VisibilityUnlocked
}
if isPublic(to) {
// TO'd to public: it's a public post.
visibility = gtsmodel.VisibilityPublic
}
return visibility, nil
}
// ExtractInteractionPolicy extracts a *gtsmodel.InteractionPolicy
// from the given Statusable created by by the given *gtsmodel.Account.
//
// Will be nil (default policy) for Statusables that have no policy
// set on them, or have a null policy. In such a case, the caller
// should assume the default policy for the status's visibility level.
func ExtractInteractionPolicy(
statusable Statusable,
owner *gtsmodel.Account,
) *gtsmodel.InteractionPolicy {
policyProp := statusable.GetGoToSocialInteractionPolicy()
if policyProp == nil || policyProp.Len() != 1 {
return nil
}
policyPropIter := policyProp.At(0)
if !policyPropIter.IsGoToSocialInteractionPolicy() {
return nil
}
policy := policyPropIter.Get()
if policy == nil {
return nil
}
return &gtsmodel.InteractionPolicy{
CanLike: extractCanLike(policy.GetGoToSocialCanLike(), owner),
CanReply: extractCanReply(policy.GetGoToSocialCanReply(), owner),
CanAnnounce: extractCanAnnounce(policy.GetGoToSocialCanAnnounce(), owner),
}
}
func extractCanLike(
prop vocab.GoToSocialCanLikeProperty,
owner *gtsmodel.Account,
) gtsmodel.PolicyRules {
if prop == nil || prop.Len() != 1 {
return gtsmodel.PolicyRules{}
}
propIter := prop.At(0)
if !propIter.IsGoToSocialCanLike() {
return gtsmodel.PolicyRules{}
}
withRules := propIter.Get()
if withRules == nil {
return gtsmodel.PolicyRules{}
}
return gtsmodel.PolicyRules{
Always: extractPolicyValues(withRules.GetGoToSocialAlways(), owner),
WithApproval: extractPolicyValues(withRules.GetGoToSocialApprovalRequired(), owner),
}
}
func extractCanReply(
prop vocab.GoToSocialCanReplyProperty,
owner *gtsmodel.Account,
) gtsmodel.PolicyRules {
if prop == nil || prop.Len() != 1 {
return gtsmodel.PolicyRules{}
}
propIter := prop.At(0)
if !propIter.IsGoToSocialCanReply() {
return gtsmodel.PolicyRules{}
}
withRules := propIter.Get()
if withRules == nil {
return gtsmodel.PolicyRules{}
}
return gtsmodel.PolicyRules{
Always: extractPolicyValues(withRules.GetGoToSocialAlways(), owner),
WithApproval: extractPolicyValues(withRules.GetGoToSocialApprovalRequired(), owner),
}
}
func extractCanAnnounce(
prop vocab.GoToSocialCanAnnounceProperty,
owner *gtsmodel.Account,
) gtsmodel.PolicyRules {
if prop == nil || prop.Len() != 1 {
return gtsmodel.PolicyRules{}
}
propIter := prop.At(0)
if !propIter.IsGoToSocialCanAnnounce() {
return gtsmodel.PolicyRules{}
}
withRules := propIter.Get()
if withRules == nil {
return gtsmodel.PolicyRules{}
}
return gtsmodel.PolicyRules{
Always: extractPolicyValues(withRules.GetGoToSocialAlways(), owner),
WithApproval: extractPolicyValues(withRules.GetGoToSocialApprovalRequired(), owner),
}
}
func extractPolicyValues[T WithIRI](
prop Property[T],
owner *gtsmodel.Account,
) gtsmodel.PolicyValues {
iris := getIRIs(prop)
PolicyValues := make(gtsmodel.PolicyValues, 0, len(iris))
for _, iri := range iris {
switch iriStr := iri.String(); iriStr {
case pub.PublicActivityPubIRI:
PolicyValues = append(PolicyValues, gtsmodel.PolicyValuePublic)
case owner.FollowersURI:
PolicyValues = append(PolicyValues, gtsmodel.PolicyValueFollowers)
case owner.FollowingURI:
PolicyValues = append(PolicyValues, gtsmodel.PolicyValueFollowing)
case owner.URI:
PolicyValues = append(PolicyValues, gtsmodel.PolicyValueAuthor)
default:
if iri.Scheme == "http" || iri.Scheme == "https" {
PolicyValues = append(PolicyValues, gtsmodel.PolicyValue(iriStr))
}
}
}
return PolicyValues
}
// ExtractSensitive extracts whether or not an item should
// be marked as sensitive according to its ActivityStreams
// sensitive property.
//
// If no sensitive property is set on the item at all, or
// if this property isn't a boolean, then false will be
// returned by default.
func ExtractSensitive(withSensitive WithSensitive) bool {
sensitiveProp := withSensitive.GetActivityStreamsSensitive()
if sensitiveProp == nil {
return false
}
for iter := sensitiveProp.Begin(); iter != sensitiveProp.End(); iter = iter.Next() {
if iter.IsXMLSchemaBoolean() {
return iter.Get()
}
}
return false
}
// ExtractSharedInbox extracts the sharedInbox URI property
// from an Actor. Returns nil if this property is not set.
func ExtractSharedInbox(withEndpoints WithEndpoints) *url.URL {
endpointsProp := withEndpoints.GetActivityStreamsEndpoints()
if endpointsProp == nil {
return nil
}
for iter := endpointsProp.Begin(); iter != endpointsProp.End(); iter = iter.Next() {
if !iter.IsActivityStreamsEndpoints() {
continue
}
endpoints := iter.Get()
if endpoints == nil {
continue
}
sharedInboxProp := endpoints.GetActivityStreamsSharedInbox()
if sharedInboxProp == nil || !sharedInboxProp.IsIRI() {
continue
}
return sharedInboxProp.GetIRI()
}
return nil
}
// ExtractPoll extracts a placeholder Poll from Pollable interface, with available options and flags populated.
func ExtractPoll(poll Pollable) (*gtsmodel.Poll, error) {
var closed time.Time
// Extract the options (votes if any) and 'multiple choice' flag.
options, multi, hideCounts, err := extractPollOptions(poll)
if err != nil {
return nil, err
}
// Extract the poll closed time,
// it's okay for this to be zero.
closedSlice := GetClosed(poll)
if len(closedSlice) == 1 {
closed = closedSlice[0]
}
// Extract the poll end time, again
// this isn't necessarily set as some
// servers support "endless" polls.
endTime := GetEndTime(poll)
if endTime.IsZero() && !closed.IsZero() {
// If no endTime is provided, but the
// poll is marked as closed, infer the
// endTime from the closed time.
endTime = closed
}
// Extract the number of voters.
voters := GetVotersCount(poll)
return &gtsmodel.Poll{
Options: optionNames(options),
Multiple: &multi,
HideCounts: &hideCounts,
Votes: optionVotes(options),
Voters: &voters,
ExpiresAt: endTime,
ClosedAt: closed,
}, nil
}
// pollOption is a simple type
// to unify a poll option name
// with the number of votes.
type pollOption struct {
Name string
Votes int
}
// optionNames extracts name strings from a slice of poll options.
func optionNames(in []pollOption) []string {
out := make([]string, len(in))
for i := range in {
out[i] = in[i].Name
}
return out
}
// optionVotes extracts vote counts from a slice of poll options.
func optionVotes(in []pollOption) []int {
out := make([]int, len(in))
for i := range in {
out[i] = in[i].Votes
}
return out
}
// extractPollOptions extracts poll option name strings, the 'multiple choice flag', and 'hideCounts' intrinsic flag properties value from Pollable.
func extractPollOptions(poll Pollable) (options []pollOption, multi bool, hide bool, err error) {
var errs gtserror.MultiError
// Iterate the oneOf property and gather poll single-choice options.
IterateOneOf(poll, func(iter vocab.ActivityStreamsOneOfPropertyIterator) {
name, votes, err := extractPollOption(iter.GetType())
if err != nil {
errs.Append(err)
return
}
if votes == nil {
hide = true
votes = new(int)
}
options = append(options, pollOption{
Name: name,
Votes: *votes,
})
})
if len(options) > 0 || len(errs) > 0 {
return options, false, hide, errs.Combine()
}
// Iterate the anyOf property and gather poll multi-choice options.
IterateAnyOf(poll, func(iter vocab.ActivityStreamsAnyOfPropertyIterator) {
name, votes, err := extractPollOption(iter.GetType())
if err != nil {
errs.Append(err)
return
}
if votes == nil {
hide = true
votes = new(int)
}
options = append(options, pollOption{
Name: name,
Votes: *votes,
})
})
if len(options) > 0 || len(errs) > 0 {
return options, true, hide, errs.Combine()
}
return nil, false, false, errors.New("poll without options")
}
// IterateOneOf will attempt to extract oneOf property from given interface, and passes each iterated item to function.
func IterateOneOf(withOneOf WithOneOf, foreach func(vocab.ActivityStreamsOneOfPropertyIterator)) {
if foreach == nil {
// nil check outside loop.
panic("nil function")
}
// Extract the one-of property from interface.
oneOfProp := withOneOf.GetActivityStreamsOneOf()
if oneOfProp == nil {
return
}
// Get start and end of iter.
start := oneOfProp.Begin()
end := oneOfProp.End()
// Pass iterated oneOf entries to given function.
for iter := start; iter != end; iter = iter.Next() {
foreach(iter)
}
}
// IterateAnyOf will attempt to extract anyOf property from given interface, and passes each iterated item to function.
func IterateAnyOf(withAnyOf WithAnyOf, foreach func(vocab.ActivityStreamsAnyOfPropertyIterator)) {
if foreach == nil {
// nil check outside loop.
panic("nil function")
}
// Extract the any-of property from interface.
anyOfProp := withAnyOf.GetActivityStreamsAnyOf()
if anyOfProp == nil {
return
}
// Get start and end of iter.
start := anyOfProp.Begin()
end := anyOfProp.End()
// Pass iterated anyOf entries to given function.
for iter := start; iter != end; iter = iter.Next() {
foreach(iter)
}
}
// extractPollOption extracts a usable poll option name from vocab.Type, or error.
func extractPollOption(t vocab.Type) (name string, votes *int, err error) {
// Check fulfills PollOptionable type
// (this accounts for nil input type).
optionable, ok := t.(PollOptionable)
if !ok {
return "", nil, fmt.Errorf("incorrect option type: %T", t)
}
// Extract PollOption from interface.
name = ExtractName(optionable)
if name == "" {
return "", nil, errors.New("empty option name")
}
// Check PollOptionable for attached 'replies' property.
repliesProp := optionable.GetActivityStreamsReplies()
if repliesProp != nil {
// Get repliesProp as the AS collection type it should be.
collection := repliesProp.GetActivityStreamsCollection()
if collection != nil {
// Extract integer value from the collection 'totalItems' property.
totalItemsProp := collection.GetActivityStreamsTotalItems()
if totalItemsProp != nil {
i := totalItemsProp.Get()
votes = &i
}
}
}
return name, votes, nil
}
// isPublic checks if at least one entry in the given
// uris slice equals the activitystreams public uri.
func isPublic(uris []*url.URL) bool {
for _, uri := range uris {
if pub.IsPublic(uri.String()) {
return true
}
}
return false
}
// isFollowers checks if at least one entry in the given
// uris slice equals the given followersURI.
func isFollowers(uris []*url.URL, followersURI string) bool {
for _, uri := range uris {
if strings.EqualFold(uri.String(), followersURI) {
return true
}
}
return false
}