gotosocial/internal/media/processingemoji.go
tobi 268f252e0d
[feature] Fetch + display custom emoji in statuses from remote instances (#807)
* start implementing remote emoji fetcher

* update status where pk

* aaa

* tidy up a little

* check size limits for emojis

* thank you linter, i love you <3

* update swagger docs

* add emoji dereference test

* make emoji max sizes configurable

* normalize db.ErrAlreadyExists
2022-09-12 13:03:23 +02:00

310 lines
10 KiB
Go

/*
GoToSocial
Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
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 media
import (
"bytes"
"context"
"fmt"
"io"
"strings"
"sync"
"sync/atomic"
"time"
"github.com/superseriousbusiness/gotosocial/internal/config"
"github.com/superseriousbusiness/gotosocial/internal/db"
"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
"github.com/superseriousbusiness/gotosocial/internal/log"
"github.com/superseriousbusiness/gotosocial/internal/storage"
"github.com/superseriousbusiness/gotosocial/internal/uris"
)
// ProcessingEmoji represents an emoji currently processing. It exposes
// various functions for retrieving data from the process.
type ProcessingEmoji struct {
mu sync.Mutex
// id of this instance's account -- pinned for convenience here so we only need to fetch it once
instanceAccountID string
/*
below fields should be set on newly created media;
emoji will be updated incrementally as media goes through processing
*/
emoji *gtsmodel.Emoji
data DataFunc
postData PostDataCallbackFunc
read bool // bool indicating that data function has been triggered already
/*
below fields represent the processing state of the static of the emoji
*/
staticState int32
/*
below pointers to database and storage are maintained so that
the media can store and update itself during processing steps
*/
database db.DB
storage storage.Driver
err error // error created during processing, if any
// track whether this emoji has already been put in the databse
insertedInDB bool
}
// EmojiID returns the ID of the underlying emoji without blocking processing.
func (p *ProcessingEmoji) EmojiID() string {
return p.emoji.ID
}
// LoadEmoji blocks until the static and fullsize image
// has been processed, and then returns the completed emoji.
func (p *ProcessingEmoji) LoadEmoji(ctx context.Context) (*gtsmodel.Emoji, error) {
p.mu.Lock()
defer p.mu.Unlock()
if err := p.store(ctx); err != nil {
return nil, err
}
if err := p.loadStatic(ctx); err != nil {
return nil, err
}
// store the result in the database before returning it
if !p.insertedInDB {
if err := p.database.PutEmoji(ctx, p.emoji); err != nil {
return nil, err
}
p.insertedInDB = true
}
return p.emoji, nil
}
// Finished returns true if processing has finished for both the thumbnail
// and full fized version of this piece of media.
func (p *ProcessingEmoji) Finished() bool {
return atomic.LoadInt32(&p.staticState) == int32(complete)
}
func (p *ProcessingEmoji) loadStatic(ctx context.Context) error {
staticState := atomic.LoadInt32(&p.staticState)
switch processState(staticState) {
case received:
// stream the original file out of storage...
stored, err := p.storage.GetStream(ctx, p.emoji.ImagePath)
if err != nil {
p.err = fmt.Errorf("loadStatic: error fetching file from storage: %s", err)
atomic.StoreInt32(&p.staticState, int32(errored))
return p.err
}
// we haven't processed a static version of this emoji yet so do it now
static, err := deriveStaticEmoji(stored, p.emoji.ImageContentType)
if err != nil {
p.err = fmt.Errorf("loadStatic: error deriving static: %s", err)
atomic.StoreInt32(&p.staticState, int32(errored))
return p.err
}
if err := stored.Close(); err != nil {
p.err = fmt.Errorf("loadStatic: error closing stored full size: %s", err)
atomic.StoreInt32(&p.staticState, int32(errored))
return p.err
}
// put the static in storage
if err := p.storage.Put(ctx, p.emoji.ImageStaticPath, static.small); err != nil {
p.err = fmt.Errorf("loadStatic: error storing static: %s", err)
atomic.StoreInt32(&p.staticState, int32(errored))
return p.err
}
p.emoji.ImageStaticFileSize = len(static.small)
// we're done processing the static version of the emoji!
atomic.StoreInt32(&p.staticState, int32(complete))
fallthrough
case complete:
return nil
case errored:
return p.err
}
return fmt.Errorf("static processing status %d unknown", p.staticState)
}
// store calls the data function attached to p if it hasn't been called yet,
// and updates the underlying attachment fields as necessary. It will then stream
// bytes from p's reader directly into storage so that it can be retrieved later.
func (p *ProcessingEmoji) store(ctx context.Context) error {
// check if we've already done this and bail early if we have
if p.read {
return nil
}
// execute the data function to get the reader out of it
reader, fileSize, err := p.data(ctx)
if err != nil {
return fmt.Errorf("store: error executing data function: %s", err)
}
maxSize := config.GetMediaEmojiRemoteMaxSize()
if fileSize > maxSize {
return fmt.Errorf("store: emoji size (%db) is larger than allowed emojiRemoteMaxSize (%db)", fileSize, maxSize)
}
// defer closing the reader when we're done with it
defer func() {
if rc, ok := reader.(io.ReadCloser); ok {
if err := rc.Close(); err != nil {
log.Errorf("store: error closing readcloser: %s", err)
}
}
}()
// extract no more than 261 bytes from the beginning of the file -- this is the header
firstBytes := make([]byte, maxFileHeaderBytes)
if _, err := reader.Read(firstBytes); err != nil {
return fmt.Errorf("store: error reading initial %d bytes: %s", maxFileHeaderBytes, err)
}
// now we have the file header we can work out the content type from it
contentType, err := parseContentType(firstBytes)
if err != nil {
return fmt.Errorf("store: error parsing content type: %s", err)
}
// bail if this is a type we can't process
if !supportedEmoji(contentType) {
return fmt.Errorf("store: content type %s was not valid for an emoji", contentType)
}
// extract the file extension
split := strings.Split(contentType, "/")
extension := split[1] // something like 'gif'
// set some additional fields on the emoji now that
// we know more about what the underlying image actually is
p.emoji.ImageURL = uris.GenerateURIForAttachment(p.instanceAccountID, string(TypeEmoji), string(SizeOriginal), p.emoji.ID, extension)
p.emoji.ImagePath = fmt.Sprintf("%s/%s/%s/%s.%s", p.instanceAccountID, TypeEmoji, SizeOriginal, p.emoji.ID, extension)
p.emoji.ImageContentType = contentType
p.emoji.ImageFileSize = fileSize
// concatenate the first bytes with the existing bytes still in the reader (thanks Mara)
multiReader := io.MultiReader(bytes.NewBuffer(firstBytes), reader)
// store this for now -- other processes can pull it out of storage as they please
if err := p.storage.PutStream(ctx, p.emoji.ImagePath, multiReader); err != nil {
return fmt.Errorf("store: error storing stream: %s", err)
}
p.read = true
if p.postData != nil {
return p.postData(ctx)
}
return nil
}
func (m *manager) preProcessEmoji(ctx context.Context, data DataFunc, postData PostDataCallbackFunc, shortcode string, id string, uri string, ai *AdditionalEmojiInfo) (*ProcessingEmoji, error) {
instanceAccount, err := m.db.GetInstanceAccount(ctx, "")
if err != nil {
return nil, fmt.Errorf("preProcessEmoji: error fetching this instance account from the db: %s", err)
}
disabled := false
visibleInPicker := true
// populate initial fields on the emoji -- some of these will be overwritten as we proceed
emoji := &gtsmodel.Emoji{
ID: id,
CreatedAt: time.Now(),
UpdatedAt: time.Now(),
Shortcode: shortcode,
Domain: "", // assume our own domain unless told otherwise
ImageRemoteURL: "",
ImageStaticRemoteURL: "",
ImageURL: "", // we don't know yet
ImageStaticURL: uris.GenerateURIForAttachment(instanceAccount.ID, string(TypeEmoji), string(SizeStatic), id, mimePng), // all static emojis are encoded as png
ImagePath: "", // we don't know yet
ImageStaticPath: fmt.Sprintf("%s/%s/%s/%s.%s", instanceAccount.ID, TypeEmoji, SizeStatic, id, mimePng), // all static emojis are encoded as png
ImageContentType: "", // we don't know yet
ImageStaticContentType: mimeImagePng, // all static emojis are encoded as png
ImageFileSize: 0,
ImageStaticFileSize: 0,
ImageUpdatedAt: time.Now(),
Disabled: &disabled,
URI: uri,
VisibleInPicker: &visibleInPicker,
CategoryID: "",
}
// check if we have additional info to add to the emoji,
// and overwrite some of the emoji fields if so
if ai != nil {
if ai.CreatedAt != nil {
emoji.CreatedAt = *ai.CreatedAt
}
if ai.Domain != nil {
emoji.Domain = *ai.Domain
}
if ai.ImageRemoteURL != nil {
emoji.ImageRemoteURL = *ai.ImageRemoteURL
}
if ai.ImageStaticRemoteURL != nil {
emoji.ImageStaticRemoteURL = *ai.ImageStaticRemoteURL
}
if ai.Disabled != nil {
emoji.Disabled = ai.Disabled
}
if ai.VisibleInPicker != nil {
emoji.VisibleInPicker = ai.VisibleInPicker
}
if ai.CategoryID != nil {
emoji.CategoryID = *ai.CategoryID
}
}
processingEmoji := &ProcessingEmoji{
instanceAccountID: instanceAccount.ID,
emoji: emoji,
data: data,
postData: postData,
staticState: int32(received),
database: m.db,
storage: m.storage,
}
return processingEmoji, nil
}