[feature] Conversations API (#3013)

* Implement conversations API

* Sort and page conversations by last status ID

* Appease linter

* Fix deleting conversations and statuses

* Refactor to make migrations automatic

* Lint

* Update tests post-merge

* Fixes from live-fire testing

* Linter caught a format problem

* Refactor tests, fix cache

* Negative test for non-DMs

* Run conversations advanced migration on testrig startup as well as regular server startup

* Document (lack of) side effects of API method for deleting a conversation

* Make not-found check less nested for readability

* Rename PutConversation to UpsertConversation

* Use util.Ptr instead of IIFE

* Reduce cache used by conversations

* Remove unnecessary TableExpr/ColumnExpr

* Use struct tags for both unique constraints on Conversation

* Make it clear how paging with GetDirectStatusIDsBatch should be used

* Let conversation paging skip conversations it can't render

* Use Bun NewDropTable

* Convert delete raw query to Bun

* Convert update raw query to Bun

* Convert latestConversationStatusesTempTable raw query partially to Bun

* Convert conversationStatusesTempTable raw query partially to Bun

* Rename field used to store result of MaxDirectStatusID

* Move advanced migrations to their own tiny processor

* Catch up util function name with main

* Remove json.… wrappers

* Remove redundant check

* Combine error checks

* Replace map with slice of structs

* Address processor/type converter comments

- Add context info for errors
- Extract some common processor code into shared methods
- Move conversation eligibility check ahead of populating conversation

* Add error context when dropping temp tables

1 files changed, 65 insertions, 0 deletions

diff --git a/internal/processing/conversations/read.go b/internal/processing/conversations/read.go
new file mode 100644
index 000000000..512a004a3
--- /dev/null
+++ b/internal/processing/conversations/read.go
@@ -0,0 +1,65 @@
+// 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 conversations
+
+import (
+	"context"
+
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/util"
+)
+
+func (p *Processor) Read(
+	ctx context.Context,
+	requestingAccount *gtsmodel.Account,
+	id string,
+) (*apimodel.Conversation, gtserror.WithCode) {
+	// Get the conversation, including participating accounts and last status.
+	conversation, errWithCode := p.getConversationOwnedBy(ctx, id, requestingAccount)
+	if errWithCode != nil {
+		return nil, errWithCode
+	}
+
+	// Mark the conversation as read.
+	conversation.Read = util.Ptr(true)
+	if err := p.state.DB.UpsertConversation(ctx, conversation, "read"); err != nil {
+		err = gtserror.Newf("DB error updating conversation %s: %w", id, err)
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	filters, mutes, errWithCode := p.getFiltersAndMutes(ctx, requestingAccount)
+	if errWithCode != nil {
+		return nil, errWithCode
+	}
+
+	apiConversation, err := p.converter.ConversationToAPIConversation(
+		ctx,
+		conversation,
+		requestingAccount,
+		filters,
+		mutes,
+	)
+	if err != nil {
+		err = gtserror.Newf("error converting conversation %s to API representation: %w", id, err)
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	return apiConversation, nil
+}