Domain block (#76)

* start work on admin domain blocking

* move stuff around + further work on domain blocks

* move + restructure processor

* prep work for deleting account

* tidy

* go fmt

* formatting

* domain blocking more work

* check domain blocks way earlier on

* progress on delete account

* delete more stuff when an account is gone

* and more...

* domain blocky block block

* get individual domain block, delete a block

internal/processing/admin/createdomainblock.go

@@ -0,0 +1,154 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 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 admin
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/sirupsen/logrus"
+	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"
+)
+
+func (p *processor) DomainBlockCreate(account *gtsmodel.Account, form *apimodel.DomainBlockCreateRequest) (*apimodel.DomainBlock, gtserror.WithCode) {
+	// first check if we already have a block -- if err == nil we already had a block so we can skip a whole lot of work
+	domainBlock := &gtsmodel.DomainBlock{}
+	err := p.db.GetWhere([]db.Where{{Key: "domain", Value: form.Domain, CaseInsensitive: true}}, domainBlock)
+	if err != nil {
+		if _, ok := err.(db.ErrNoEntries); !ok {
+			// something went wrong in the DB
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("DomainBlockCreate: db error checking for existence of domain block %s: %s", form.Domain, err))
+		}
+
+		// there's no block for this domain yet so create one
+		// note: we take a new ulid from timestamp here in case we need to sort blocks
+		blockID, err := id.NewULID()
+		if err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("DomainBlockCreate: error creating id for new domain block %s: %s", form.Domain, err))
+		}
+
+		domainBlock = &gtsmodel.DomainBlock{
+			ID:                 blockID,
+			Domain:             form.Domain,
+			CreatedByAccountID: account.ID,
+			PrivateComment:     form.PrivateComment,
+			PublicComment:      form.PublicComment,
+			Obfuscate:          form.Obfuscate,
+		}
+
+		// put the new block in the database
+		if err := p.db.Put(domainBlock); err != nil {
+			if _, ok := err.(db.ErrAlreadyExists); !ok {
+				// there's a real error creating the block
+				return nil, gtserror.NewErrorInternalError(fmt.Errorf("DomainBlockCreate: db error putting new domain block %s: %s", form.Domain, err))
+			}
+		}
+
+		// process the side effects of the domain block asynchronously since it might take a while
+		go p.initiateDomainBlockSideEffects(account, domainBlock) // TODO: add this to a queuing system so it can retry/resume
+	}
+
+	mastoDomainBlock, err := p.tc.DomainBlockToMasto(domainBlock, false)
+	if err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("DomainBlockCreate: error converting domain block to frontend/masto representation %s: %s", form.Domain, err))
+	}
+
+	return mastoDomainBlock, nil
+}
+
+// initiateDomainBlockSideEffects should be called asynchronously, to process the side effects of a domain block:
+//
+// 1. Strip most info away from the instance entry for the domain.
+// 2. Delete the instance account for that instance if it exists.
+// 3. Select all accounts from this instance and pass them through the delete functionality of the processor.
+func (p *processor) initiateDomainBlockSideEffects(account *gtsmodel.Account, block *gtsmodel.DomainBlock) {
+	l := p.log.WithFields(logrus.Fields{
+		"func":   "domainBlockProcessSideEffects",
+		"domain": block.Domain,
+	})
+
+	l.Debug("processing domain block side effects")
+
+	// if we have an instance entry for this domain, update it with the new block ID and clear all fields
+	instance := &gtsmodel.Instance{}
+	if err := p.db.GetWhere([]db.Where{{Key: "domain", Value: block.Domain, CaseInsensitive: true}}, instance); err == nil {
+		instance.Title = ""
+		instance.UpdatedAt = time.Now()
+		instance.SuspendedAt = time.Now()
+		instance.DomainBlockID = block.ID
+		instance.ShortDescription = ""
+		instance.Description = ""
+		instance.Terms = ""
+		instance.ContactEmail = ""
+		instance.ContactAccountUsername = ""
+		instance.ContactAccountID = ""
+		instance.Version = ""
+		if err := p.db.UpdateByID(instance.ID, instance); err != nil {
+			l.Errorf("domainBlockProcessSideEffects: db error updating instance: %s", err)
+		}
+		l.Debug("domainBlockProcessSideEffects: instance entry updated")
+	}
+
+	// if we have an instance account for this instance, delete it
+	if err := p.db.DeleteWhere([]db.Where{{Key: "username", Value: block.Domain, CaseInsensitive: true}}, &gtsmodel.Account{}); err != nil {
+		l.Errorf("domainBlockProcessSideEffects: db error removing instance account: %s", err)
+	}
+
+	// delete accounts through the normal account deletion system (which should also delete media + posts + remove posts from timelines)
+
+	limit := 20      // just select 20 accounts at a time so we don't nuke our DB/mem with one huge query
+	var maxID string // this is initially an empty string so we'll start at the top of accounts list (sorted by ID)
+
+selectAccountsLoop:
+	for {
+		accounts, err := p.db.GetAccountsForInstance(block.Domain, maxID, limit)
+		if err != nil {
+			if _, ok := err.(db.ErrNoEntries); ok {
+				// no accounts left for this instance so we're done
+				l.Infof("domainBlockProcessSideEffects: done iterating through accounts for domain %s", block.Domain)
+				break selectAccountsLoop
+			}
+			// an actual error has occurred
+			l.Errorf("domainBlockProcessSideEffects: db error selecting accounts for domain %s: %s", block.Domain, err)
+			break selectAccountsLoop
+		}
+
+		for i, a := range accounts {
+			l.Debugf("putting delete for account %s in the clientAPI channel", a.Username)
+
+			// pass the account delete through the client api channel for processing
+			p.fromClientAPI <- gtsmodel.FromClientAPI{
+				APObjectType:   gtsmodel.ActivityStreamsPerson,
+				APActivityType: gtsmodel.ActivityStreamsDelete,
+				GTSModel:       a,
+				OriginAccount:  account,
+				TargetAccount:  a,
+			}
+
+			// if this is the last account in the slice, set the maxID appropriately for the next query
+			if i == len(accounts)-1 {
+				maxID = a.ID
+			}
+		}
+	}
+}