[chore] Deinterface processor and subprocessors (#1501)

* [chore] Deinterface processor and subprocessors

* expose subprocessors via function calls

* missing license header

internal/processing/account/follow.go

@@ -0,0 +1,205 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2023 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 account
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/superseriousbusiness/gotosocial/internal/ap"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/id"
+	"github.com/superseriousbusiness/gotosocial/internal/messages"
+	"github.com/superseriousbusiness/gotosocial/internal/uris"
+)
+
+// FollowCreate handles a follow request to an account, either remote or local.
+func (p *Processor) FollowCreate(ctx context.Context, requestingAccount *gtsmodel.Account, form *apimodel.AccountFollowRequest) (*apimodel.Relationship, gtserror.WithCode) {
+	// if there's a block between the accounts we shouldn't create the request ofc
+	if blocked, err := p.db.IsBlocked(ctx, requestingAccount.ID, form.ID, true); err != nil {
+		return nil, gtserror.NewErrorInternalError(err)
+	} else if blocked {
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("block exists between accounts"))
+	}
+
+	// make sure the target account actually exists in our db
+	targetAcct, err := p.db.GetAccountByID(ctx, form.ID)
+	if err != nil {
+		if err == db.ErrNoEntries {
+			return nil, gtserror.NewErrorNotFound(fmt.Errorf("accountfollowcreate: account %s not found in the db: %s", form.ID, err))
+		}
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	// check if a follow exists already
+	if follows, err := p.db.IsFollowing(ctx, requestingAccount, targetAcct); err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("accountfollowcreate: error checking follow in db: %s", err))
+	} else if follows {
+		// already follows so just return the relationship
+		return p.RelationshipGet(ctx, requestingAccount, form.ID)
+	}
+
+	// check if a follow request exists already
+	if followRequested, err := p.db.IsFollowRequested(ctx, requestingAccount, targetAcct); err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("accountfollowcreate: error checking follow request in db: %s", err))
+	} else if followRequested {
+		// already follow requested so just return the relationship
+		return p.RelationshipGet(ctx, requestingAccount, form.ID)
+	}
+
+	// check for attempt to follow self
+	if requestingAccount.ID == targetAcct.ID {
+		return nil, gtserror.NewErrorNotAcceptable(fmt.Errorf("accountfollowcreate: account %s cannot follow itself", requestingAccount.ID))
+	}
+
+	// make the follow request
+	newFollowID, err := id.NewRandomULID()
+	if err != nil {
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	showReblogs := true
+	notify := false
+	fr := &gtsmodel.FollowRequest{
+		ID:              newFollowID,
+		AccountID:       requestingAccount.ID,
+		TargetAccountID: form.ID,
+		ShowReblogs:     &showReblogs,
+		URI:             uris.GenerateURIForFollow(requestingAccount.Username, newFollowID),
+		Notify:          &notify,
+	}
+	if form.Reblogs != nil {
+		fr.ShowReblogs = form.Reblogs
+	}
+	if form.Notify != nil {
+		fr.Notify = form.Notify
+	}
+
+	// whack it in the database
+	if err := p.db.Put(ctx, fr); err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("accountfollowcreate: error creating follow request in db: %s", err))
+	}
+
+	// if it's a local account that's not locked we can just straight up accept the follow request
+	if !*targetAcct.Locked && targetAcct.Domain == "" {
+		if _, err := p.db.AcceptFollowRequest(ctx, requestingAccount.ID, form.ID); err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("accountfollowcreate: error accepting folow request for local unlocked account: %s", err))
+		}
+		// return the new relationship
+		return p.RelationshipGet(ctx, requestingAccount, form.ID)
+	}
+
+	// otherwise we leave the follow request as it is and we handle the rest of the process asynchronously
+	p.clientWorker.Queue(messages.FromClientAPI{
+		APObjectType:   ap.ActivityFollow,
+		APActivityType: ap.ActivityCreate,
+		GTSModel:       fr,
+		OriginAccount:  requestingAccount,
+		TargetAccount:  targetAcct,
+	})
+
+	// return whatever relationship results from this
+	return p.RelationshipGet(ctx, requestingAccount, form.ID)
+}
+
+// FollowRemove handles the removal of a follow/follow request to an account, either remote or local.
+func (p *Processor) FollowRemove(ctx context.Context, requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode) {
+	// if there's a block between the accounts we shouldn't do anything
+	blocked, err := p.db.IsBlocked(ctx, requestingAccount.ID, targetAccountID, true)
+	if err != nil {
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+	if blocked {
+		return nil, gtserror.NewErrorNotFound(fmt.Errorf("AccountFollowRemove: block exists between accounts"))
+	}
+
+	// make sure the target account actually exists in our db
+	targetAcct, err := p.db.GetAccountByID(ctx, targetAccountID)
+	if err != nil {
+		if err == db.ErrNoEntries {
+			return nil, gtserror.NewErrorNotFound(fmt.Errorf("AccountFollowRemove: account %s not found in the db: %s", targetAccountID, err))
+		}
+	}
+
+	// check if a follow request exists, and remove it if it does (storing the URI for later)
+	var frChanged bool
+	var frURI string
+	fr := &gtsmodel.FollowRequest{}
+	if err := p.db.GetWhere(ctx, []db.Where{
+		{Key: "account_id", Value: requestingAccount.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, fr); err == nil {
+		frURI = fr.URI
+		if err := p.db.DeleteByID(ctx, fr.ID, fr); err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("AccountFollowRemove: error removing follow request from db: %s", err))
+		}
+		frChanged = true
+	}
+
+	// now do the same thing for any existing follow
+	var fChanged bool
+	var fURI string
+	f := &gtsmodel.Follow{}
+	if err := p.db.GetWhere(ctx, []db.Where{
+		{Key: "account_id", Value: requestingAccount.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, f); err == nil {
+		fURI = f.URI
+		if err := p.db.DeleteByID(ctx, f.ID, f); err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("AccountFollowRemove: error removing follow from db: %s", err))
+		}
+		fChanged = true
+	}
+
+	// follow request status changed so send the UNDO activity to the channel for async processing
+	if frChanged {
+		p.clientWorker.Queue(messages.FromClientAPI{
+			APObjectType:   ap.ActivityFollow,
+			APActivityType: ap.ActivityUndo,
+			GTSModel: &gtsmodel.Follow{
+				AccountID:       requestingAccount.ID,
+				TargetAccountID: targetAccountID,
+				URI:             frURI,
+			},
+			OriginAccount: requestingAccount,
+			TargetAccount: targetAcct,
+		})
+	}
+
+	// follow status changed so send the UNDO activity to the channel for async processing
+	if fChanged {
+		p.clientWorker.Queue(messages.FromClientAPI{
+			APObjectType:   ap.ActivityFollow,
+			APActivityType: ap.ActivityUndo,
+			GTSModel: &gtsmodel.Follow{
+				AccountID:       requestingAccount.ID,
+				TargetAccountID: targetAccountID,
+				URI:             fURI,
+			},
+			OriginAccount: requestingAccount,
+			TargetAccount: targetAcct,
+		})
+	}
+
+	// return whatever relationship results from all this
+	return p.RelationshipGet(ctx, requestingAccount, targetAccountID)
+}