[feature] Clean up/uncache remote media (#407)

* Add whereNotEmptyAndNotNull

* Add GetRemoteOlderThanDays

* Add GetRemoteOlderThanDays

* Add PruneRemote to Manager interface

* Start implementing PruneRemote

* add new attachment + status to tests

* fix up and test GetRemoteOlderThan

* fix bad import

* PruneRemote: return number pruned

* add Cached column to mediaattachment

* update + test pruneRemote

* update mediaTest

* use Cached column

* upstep bun to latest version

* embed structs in mediaAttachment

* migrate mediaAttachment to new format

* don't default cached to true

* select only remote media

* update db dependencies

* step bun back to last working version

* update pruneRemote to use Cached field

* fix storage path of test attachments

* add recache logic to manager

* fix trimmed aspect ratio

* test prune and recache

* return errwithcode

* tidy up different paths for emoji vs attachment

* fix incorrect thumbnail type being stored

* expose TransportController to media processor

* implement tee-ing recached content

* add thoughts of dog to test fedi attachments

* test get remote files

* add comment on PruneRemote

* add postData cleanup to recache

* test thumbnail fetching

* add incredible diagram

* go mod tidy

* buffer pipes for recache streaming

* test for client stops reading after 1kb

* add media-remote-cache-days to config

* add cron package

* wrap logrus so it's available to cron

* start and stop cron jobs gracefully

1 files changed, 208 insertions, 0 deletions

diff --git a/internal/processing/media/getfile_test.go b/internal/processing/media/getfile_test.go
new file mode 100644
index 000000000..4d7bc4621
--- /dev/null
+++ b/internal/processing/media/getfile_test.go
@@ -0,0 +1,208 @@
+/*
+   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_test
+
+import (
+	"context"
+	"io"
+	"path"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/suite"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/media"
+)
+
+type GetFileTestSuite struct {
+	MediaStandardTestSuite
+}
+
+func (suite *GetFileTestSuite) TestGetRemoteFileCached() {
+	ctx := context.Background()
+
+	testAttachment := suite.testAttachments["remote_account_1_status_1_attachment_1"]
+	fileName := path.Base(testAttachment.File.Path)
+	requestingAccount := suite.testAccounts["local_account_1"]
+
+	content, errWithCode := suite.mediaProcessor.GetFile(ctx, requestingAccount, &apimodel.GetContentRequestForm{
+		AccountID: testAttachment.AccountID,
+		MediaType: string(media.TypeAttachment),
+		MediaSize: string(media.SizeOriginal),
+		FileName:  fileName,
+	})
+
+	suite.NoError(errWithCode)
+	suite.NotNil(content)
+	b, err := io.ReadAll(content.Content)
+	suite.NoError(err)
+
+	if closer, ok := content.Content.(io.Closer); ok {
+		suite.NoError(closer.Close())
+	}
+
+	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].Data, b)
+	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].ContentType, content.ContentType)
+	suite.EqualValues(len(suite.testRemoteAttachments[testAttachment.RemoteURL].Data), content.ContentLength)
+}
+
+func (suite *GetFileTestSuite) TestGetRemoteFileUncached() {
+	ctx := context.Background()
+
+	// uncache the file from local
+	testAttachment := suite.testAttachments["remote_account_1_status_1_attachment_1"]
+	testAttachment.Cached = false
+	err := suite.db.UpdateByPrimaryKey(ctx, testAttachment)
+	suite.NoError(err)
+	err = suite.storage.Delete(testAttachment.File.Path)
+	suite.NoError(err)
+	err = suite.storage.Delete(testAttachment.Thumbnail.Path)
+	suite.NoError(err)
+
+	// now fetch it
+	fileName := path.Base(testAttachment.File.Path)
+	requestingAccount := suite.testAccounts["local_account_1"]
+
+	content, errWithCode := suite.mediaProcessor.GetFile(ctx, requestingAccount, &apimodel.GetContentRequestForm{
+		AccountID: testAttachment.AccountID,
+		MediaType: string(media.TypeAttachment),
+		MediaSize: string(media.SizeOriginal),
+		FileName:  fileName,
+	})
+
+	suite.NoError(errWithCode)
+	suite.NotNil(content)
+	b, err := io.ReadAll(content.Content)
+	suite.NoError(err)
+
+	if closer, ok := content.Content.(io.Closer); ok {
+		suite.NoError(closer.Close())
+	}
+
+	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].Data, b)
+	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].ContentType, content.ContentType)
+	suite.EqualValues(len(suite.testRemoteAttachments[testAttachment.RemoteURL].Data), content.ContentLength)
+	time.Sleep(2 * time.Second) // wait a few seconds for the media manager to finish doing stuff
+
+	// the attachment should be updated in the database
+	dbAttachment, err := suite.db.GetAttachmentByID(ctx, testAttachment.ID)
+	suite.NoError(err)
+	suite.True(dbAttachment.Cached)
+
+	// the file should be back in storage at the same path as before
+	refreshedBytes, err := suite.storage.Get(testAttachment.File.Path)
+	suite.NoError(err)
+	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].Data, refreshedBytes)
+}
+
+func (suite *GetFileTestSuite) TestGetRemoteFileUncachedInterrupted() {
+	ctx := context.Background()
+
+	// uncache the file from local
+	testAttachment := suite.testAttachments["remote_account_1_status_1_attachment_1"]
+	testAttachment.Cached = false
+	err := suite.db.UpdateByPrimaryKey(ctx, testAttachment)
+	suite.NoError(err)
+	err = suite.storage.Delete(testAttachment.File.Path)
+	suite.NoError(err)
+	err = suite.storage.Delete(testAttachment.Thumbnail.Path)
+	suite.NoError(err)
+
+	// now fetch it
+	fileName := path.Base(testAttachment.File.Path)
+	requestingAccount := suite.testAccounts["local_account_1"]
+
+	content, errWithCode := suite.mediaProcessor.GetFile(ctx, requestingAccount, &apimodel.GetContentRequestForm{
+		AccountID: testAttachment.AccountID,
+		MediaType: string(media.TypeAttachment),
+		MediaSize: string(media.SizeOriginal),
+		FileName:  fileName,
+	})
+
+	suite.NoError(errWithCode)
+	suite.NotNil(content)
+
+	// only read the first kilobyte and then stop
+	b := make([]byte, 1024)
+	_, err = content.Content.Read(b)
+	suite.NoError(err)
+
+	// close the reader
+	if closer, ok := content.Content.(io.Closer); ok {
+		suite.NoError(closer.Close())
+	}
+
+	time.Sleep(2 * time.Second) // wait a few seconds for the media manager to finish doing stuff
+
+	// the attachment should still be updated in the database even though the caller hung up
+	dbAttachment, err := suite.db.GetAttachmentByID(ctx, testAttachment.ID)
+	suite.NoError(err)
+	suite.True(dbAttachment.Cached)
+
+	// the file should be back in storage at the same path as before
+	refreshedBytes, err := suite.storage.Get(testAttachment.File.Path)
+	suite.NoError(err)
+	suite.Equal(suite.testRemoteAttachments[testAttachment.RemoteURL].Data, refreshedBytes)
+}
+
+func (suite *GetFileTestSuite) TestGetRemoteFileThumbnailUncached() {
+	ctx := context.Background()
+	testAttachment := suite.testAttachments["remote_account_1_status_1_attachment_1"]
+
+	// fetch the existing thumbnail bytes from storage first
+	thumbnailBytes, err := suite.storage.Get(testAttachment.Thumbnail.Path)
+	suite.NoError(err)
+
+	// uncache the file from local
+	testAttachment.Cached = false
+	err = suite.db.UpdateByPrimaryKey(ctx, testAttachment)
+	suite.NoError(err)
+	err = suite.storage.Delete(testAttachment.File.Path)
+	suite.NoError(err)
+	err = suite.storage.Delete(testAttachment.Thumbnail.Path)
+	suite.NoError(err)
+
+	// now fetch the thumbnail
+	fileName := path.Base(testAttachment.File.Path)
+	requestingAccount := suite.testAccounts["local_account_1"]
+
+	content, errWithCode := suite.mediaProcessor.GetFile(ctx, requestingAccount, &apimodel.GetContentRequestForm{
+		AccountID: testAttachment.AccountID,
+		MediaType: string(media.TypeAttachment),
+		MediaSize: string(media.SizeSmall),
+		FileName:  fileName,
+	})
+
+	suite.NoError(errWithCode)
+	suite.NotNil(content)
+	b, err := io.ReadAll(content.Content)
+	suite.NoError(err)
+
+	if closer, ok := content.Content.(io.Closer); ok {
+		suite.NoError(closer.Close())
+	}
+
+	suite.Equal(thumbnailBytes, b)
+	suite.Equal("image/jpeg", content.ContentType)
+	suite.EqualValues(testAttachment.Thumbnail.FileSize, content.ContentLength)
+}
+
+func TestGetFileTestSuite(t *testing.T) {
+	suite.Run(t, &GetFileTestSuite{})
+}