[feature] Refetch emojis when they change on remote instances (#905)

* select emoji using image_static_url

* use updated on AP emojis

* allow refetch of updated emojis

* cheeky workaround for test

* clean up old files for refreshed emoji

* check error for originalPostData

* shorten GetEmojiByStaticImageURL

* delete kirby (sorry nintendo)

2 files changed, 27 insertions, 20 deletions

diff --git a/internal/processing/admin/createemoji.go b/internal/processing/admin/createemoji.go
index 50399279c..93ae17496 100644
--- a/internal/processing/admin/createemoji.go
+++ b/internal/processing/admin/createemoji.go
@@ -57,7 +57,7 @@ func (p *processor) EmojiCreate(ctx context.Context, account *gtsmodel.Account,
 		return f, form.Image.Size, err
 	}
 
-	processingEmoji, err := p.mediaManager.ProcessEmoji(ctx, data, nil, form.Shortcode, emojiID, emojiURI, nil)
+	processingEmoji, err := p.mediaManager.ProcessEmoji(ctx, data, nil, form.Shortcode, emojiID, emojiURI, nil, false)
 	if err != nil {
 		return nil, gtserror.NewErrorInternalError(fmt.Errorf("error processing emoji: %s", err), "error processing emoji")
 	}
diff --git a/internal/processing/media/getfile.go b/internal/processing/media/getfile.go
index 104bca770..693b8685b 100644
--- a/internal/processing/media/getfile.go
+++ b/internal/processing/media/getfile.go
@@ -30,9 +30,10 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 	"github.com/superseriousbusiness/gotosocial/internal/media"
+	"github.com/superseriousbusiness/gotosocial/internal/uris"
 )
 
-func (p *processor) GetFile(ctx context.Context, account *gtsmodel.Account, form *apimodel.GetContentRequestForm) (*apimodel.Content, gtserror.WithCode) {
+func (p *processor) GetFile(ctx context.Context, requestingAccount *gtsmodel.Account, form *apimodel.GetContentRequestForm) (*apimodel.Content, gtserror.WithCode) {
 	// parse the form fields
 	mediaSize, err := media.ParseMediaSize(form.MediaSize)
 	if err != nil {
@@ -49,25 +50,25 @@ func (p *processor) GetFile(ctx context.Context, account *gtsmodel.Account, form
 		return nil, gtserror.NewErrorNotFound(fmt.Errorf("file name %s not parseable", form.FileName))
 	}
 	wantedMediaID := spl[0]
-	expectedAccountID := form.AccountID
+	owningAccountID := form.AccountID
 
 	// get the account that owns the media and make sure it's not suspended
-	acct, err := p.db.GetAccountByID(ctx, expectedAccountID)
+	owningAccount, err := p.db.GetAccountByID(ctx, owningAccountID)
 	if err != nil {
-		return nil, gtserror.NewErrorNotFound(fmt.Errorf("account with id %s could not be selected from the db: %s", expectedAccountID, err))
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("account with id %s could not be selected from the db: %s", owningAccountID, err))
 	}
-	if !acct.SuspendedAt.IsZero() {
-		return nil, gtserror.NewErrorNotFound(fmt.Errorf("account with id %s is suspended", expectedAccountID))
+	if !owningAccount.SuspendedAt.IsZero() {
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("account with id %s is suspended", owningAccountID))
 	}
 
 	// make sure the requesting account and the media account don't block each other
-	if account != nil {
-		blocked, err := p.db.IsBlocked(ctx, account.ID, expectedAccountID, true)
+	if requestingAccount != nil {
+		blocked, err := p.db.IsBlocked(ctx, requestingAccount.ID, owningAccountID, true)
 		if err != nil {
-			return nil, gtserror.NewErrorNotFound(fmt.Errorf("block status could not be established between accounts %s and %s: %s", expectedAccountID, account.ID, err))
+			return nil, gtserror.NewErrorNotFound(fmt.Errorf("block status could not be established between accounts %s and %s: %s", owningAccountID, requestingAccount.ID, err))
 		}
 		if blocked {
-			return nil, gtserror.NewErrorNotFound(fmt.Errorf("block exists between accounts %s and %s", expectedAccountID, account.ID))
+			return nil, gtserror.NewErrorNotFound(fmt.Errorf("block exists between accounts %s and %s", owningAccountID, requestingAccount.ID))
 		}
 	}
 
@@ -75,15 +76,15 @@ func (p *processor) GetFile(ctx context.Context, account *gtsmodel.Account, form
 	// so we need to take different steps depending on the media type being requested
 	switch mediaType {
 	case media.TypeEmoji:
-		return p.getEmojiContent(ctx, wantedMediaID, mediaSize)
+		return p.getEmojiContent(ctx, wantedMediaID, owningAccountID, mediaSize)
 	case media.TypeAttachment, media.TypeHeader, media.TypeAvatar:
-		return p.getAttachmentContent(ctx, account, wantedMediaID, expectedAccountID, mediaSize)
+		return p.getAttachmentContent(ctx, requestingAccount, wantedMediaID, owningAccountID, mediaSize)
 	default:
 		return nil, gtserror.NewErrorNotFound(fmt.Errorf("media type %s not recognized", mediaType))
 	}
 }
 
-func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount *gtsmodel.Account, wantedMediaID string, expectedAccountID string, mediaSize media.Size) (*apimodel.Content, gtserror.WithCode) {
+func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount *gtsmodel.Account, wantedMediaID string, owningAccountID string, mediaSize media.Size) (*apimodel.Content, gtserror.WithCode) {
 	attachmentContent := &apimodel.Content{}
 	var storagePath string
 
@@ -93,8 +94,8 @@ func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount
 		return nil, gtserror.NewErrorNotFound(fmt.Errorf("attachment %s could not be taken from the db: %s", wantedMediaID, err))
 	}
 
-	if a.AccountID != expectedAccountID {
-		return nil, gtserror.NewErrorNotFound(fmt.Errorf("attachment %s is not owned by %s", wantedMediaID, expectedAccountID))
+	if a.AccountID != owningAccountID {
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("attachment %s is not owned by %s", wantedMediaID, owningAccountID))
 	}
 
 	// get file information from the attachment depending on the requested media size
@@ -227,17 +228,23 @@ func (p *processor) getAttachmentContent(ctx context.Context, requestingAccount
 	return attachmentContent, nil
 }
 
-func (p *processor) getEmojiContent(ctx context.Context, wantedEmojiID string, emojiSize media.Size) (*apimodel.Content, gtserror.WithCode) {
+func (p *processor) getEmojiContent(ctx context.Context, fileName string, owningAccountID string, emojiSize media.Size) (*apimodel.Content, gtserror.WithCode) {
 	emojiContent := &apimodel.Content{}
 	var storagePath string
 
-	e, err := p.db.GetEmojiByID(ctx, wantedEmojiID)
+	// reconstruct the static emoji image url -- reason
+	// for using the static URL rather than full size url
+	// is that static emojis are always encoded as png,
+	// so this is more reliable than using full size url
+	imageStaticURL := uris.GenerateURIForAttachment(owningAccountID, string(media.TypeEmoji), string(media.SizeStatic), fileName, "png")
+
+	e, err := p.db.GetEmojiByStaticURL(ctx, imageStaticURL)
 	if err != nil {
-		return nil, gtserror.NewErrorNotFound(fmt.Errorf("emoji %s could not be taken from the db: %s", wantedEmojiID, err))
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("emoji %s could not be taken from the db: %s", fileName, err))
 	}
 
 	if *e.Disabled {
-		return nil, gtserror.NewErrorNotFound(fmt.Errorf("emoji %s has been disabled", wantedEmojiID))
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("emoji %s has been disabled", fileName))
 	}
 
 	switch emojiSize {