[feature] Allow import of following and blocks via CSV (#3150)

* [feature] Import follows + blocks via settings panel

* test import follows

1 files changed, 374 insertions, 0 deletions

diff --git a/internal/processing/account/import.go b/internal/processing/account/import.go
new file mode 100644
index 000000000..200d971b8
--- /dev/null
+++ b/internal/processing/account/import.go
@@ -0,0 +1,374 @@
+// 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 account
+
+import (
+	"context"
+	"encoding/csv"
+	"errors"
+	"fmt"
+	"mime/multipart"
+
+	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/log"
+)
+
+func (p *Processor) ImportData(
+	ctx context.Context,
+	requester *gtsmodel.Account,
+	data *multipart.FileHeader,
+	importType string,
+	overwrite bool,
+) gtserror.WithCode {
+	switch importType {
+
+	case "following":
+		return p.importFollowing(
+			ctx,
+			requester,
+			data,
+			overwrite,
+		)
+
+	case "blocks":
+		return p.importBlocks(
+			ctx,
+			requester,
+			data,
+			overwrite,
+		)
+
+	default:
+		const text = "import type not yet supported"
+		return gtserror.NewErrorUnprocessableEntity(errors.New(text), text)
+	}
+}
+
+func (p *Processor) importFollowing(
+	ctx context.Context,
+	requester *gtsmodel.Account,
+	followingData *multipart.FileHeader,
+	overwrite bool,
+) gtserror.WithCode {
+	file, err := followingData.Open()
+	if err != nil {
+		err := fmt.Errorf("error opening following data file: %w", err)
+		return gtserror.NewErrorBadRequest(err, err.Error())
+	}
+	defer file.Close()
+
+	// Parse records out of the file.
+	records, err := csv.NewReader(file).ReadAll()
+	if err != nil {
+		err := fmt.Errorf("error reading following data file: %w", err)
+		return gtserror.NewErrorBadRequest(err, err.Error())
+	}
+
+	// Convert the records into a slice of barebones follows.
+	//
+	// Only TargetAccount.Username, TargetAccount.Domain,
+	// and ShowReblogs will be set on each Follow.
+	follows, err := p.converter.CSVToFollowing(ctx, records)
+	if err != nil {
+		err := fmt.Errorf("error converting records to follows: %w", err)
+		return gtserror.NewErrorBadRequest(err, err.Error())
+	}
+
+	// Do remaining processing of this import asynchronously.
+	f := importFollowingAsyncF(p, requester, follows, overwrite)
+	p.state.Workers.Processing.Queue.Push(f)
+
+	return nil
+}
+
+func importFollowingAsyncF(
+	p *Processor,
+	requester *gtsmodel.Account,
+	follows []*gtsmodel.Follow,
+	overwrite bool,
+) func(context.Context) {
+	return func(ctx context.Context) {
+		// Map used to store wanted
+		// follow targets (if overwriting).
+		var wantedFollows map[string]struct{}
+
+		if overwrite {
+			// If we're overwriting, we need to get current
+			// follow(-req)s owned by requester *before*
+			// making any changes, so that we can remove
+			// unwanted follows after we've created new ones.
+			prevFollows, err := p.state.DB.GetAccountFollows(ctx, requester.ID, nil)
+			if err != nil {
+				log.Errorf(ctx, "db error getting following: %v", err)
+				return
+			}
+
+			prevFollowReqs, err := p.state.DB.GetAccountFollowRequesting(ctx, requester.ID, nil)
+			if err != nil {
+				log.Errorf(ctx, "db error getting follow requesting: %v", err)
+				return
+			}
+
+			// Initialize new follows map.
+			wantedFollows = make(map[string]struct{}, len(follows))
+
+			// Once we've created (or tried to create)
+			// the required follows, go through previous
+			// follow(-request)s and remove unwanted ones.
+			defer func() {
+
+				// AccountIDs to unfollow.
+				toRemove := []string{}
+
+				// Check previous follows.
+				for _, prev := range prevFollows {
+					username := prev.TargetAccount.Username
+					domain := prev.TargetAccount.Domain
+
+					_, wanted := wantedFollows[username+"@"+domain]
+					if !wanted {
+						toRemove = append(toRemove, prev.TargetAccountID)
+					}
+				}
+
+				// Now any pending follow requests.
+				for _, prev := range prevFollowReqs {
+					username := prev.TargetAccount.Username
+					domain := prev.TargetAccount.Domain
+
+					_, wanted := wantedFollows[username+"@"+domain]
+					if !wanted {
+						toRemove = append(toRemove, prev.TargetAccountID)
+					}
+				}
+
+				// Remove each discovered
+				// unwanted follow.
+				for _, accountID := range toRemove {
+					if _, errWithCode := p.FollowRemove(
+						ctx,
+						requester,
+						accountID,
+					); errWithCode != nil {
+						log.Errorf(ctx, "could not unfollow account: %v", errWithCode.Unwrap())
+						continue
+					}
+				}
+			}()
+		}
+
+		// Go through the follows parsed from CSV
+		// file, and create / update each one.
+		for _, follow := range follows {
+			var (
+				// Username of the target.
+				username = follow.TargetAccount.Username
+
+				// Domain of the target.
+				// Empty for our domain.
+				domain = follow.TargetAccount.Domain
+
+				// Show reblogs on
+				// the new follow.
+				showReblogs = follow.ShowReblogs
+			)
+
+			if overwrite {
+				// We'll be overwriting, so store
+				// this new follow in our handy map.
+				wantedFollows[username+"@"+domain] = struct{}{}
+			}
+
+			// Get the target account, dereferencing it if necessary.
+			targetAcct, _, err := p.federator.Dereferencer.GetAccountByUsernameDomain(
+				ctx,
+				requester.Username,
+				username,
+				domain,
+			)
+			if err != nil {
+				log.Errorf(ctx, "could not retrieve account: %v", err)
+				continue
+			}
+
+			// Use the processor's FollowCreate function
+			// to create or update the follow. This takes
+			// account of existing follows, and also sends
+			// the follow to the FromClientAPI processor.
+			if _, errWithCode := p.FollowCreate(
+				ctx,
+				requester,
+				&apimodel.AccountFollowRequest{
+					ID:      targetAcct.ID,
+					Reblogs: showReblogs,
+				},
+			); errWithCode != nil {
+				log.Errorf(ctx, "could not follow account: %v", errWithCode.Unwrap())
+				continue
+			}
+		}
+	}
+}
+
+func (p *Processor) importBlocks(
+	ctx context.Context,
+	requester *gtsmodel.Account,
+	blocksData *multipart.FileHeader,
+	overwrite bool,
+) gtserror.WithCode {
+	file, err := blocksData.Open()
+	if err != nil {
+		err := fmt.Errorf("error opening blocks data file: %w", err)
+		return gtserror.NewErrorBadRequest(err, err.Error())
+	}
+	defer file.Close()
+
+	// Parse records out of the file.
+	records, err := csv.NewReader(file).ReadAll()
+	if err != nil {
+		err := fmt.Errorf("error reading blocks data file: %w", err)
+		return gtserror.NewErrorBadRequest(err, err.Error())
+	}
+
+	// Convert the records into a slice of barebones blocks.
+	//
+	// Only TargetAccount.Username and TargetAccount.Domain,
+	// will be set on each Block.
+	blocks, err := p.converter.CSVToBlocks(ctx, records)
+	if err != nil {
+		err := fmt.Errorf("error converting records to blocks: %w", err)
+		return gtserror.NewErrorBadRequest(err, err.Error())
+	}
+
+	// Do remaining processing of this import asynchronously.
+	f := importBlocksAsyncF(p, requester, blocks, overwrite)
+	p.state.Workers.Processing.Queue.Push(f)
+
+	return nil
+}
+
+func importBlocksAsyncF(
+	p *Processor,
+	requester *gtsmodel.Account,
+	blocks []*gtsmodel.Block,
+	overwrite bool,
+) func(context.Context) {
+	return func(ctx context.Context) {
+		// Map used to store wanted
+		// block targets (if overwriting).
+		var wantedBlocks map[string]struct{}
+
+		if overwrite {
+			// If we're overwriting, we need to get current
+			// blocks owned by requester *before* making any
+			// changes, so that we can remove unwanted blocks
+			// after we've created new ones.
+			var (
+				prevBlocks []*gtsmodel.Block
+				err        error
+			)
+
+			prevBlocks, err = p.state.DB.GetAccountBlocks(ctx, requester.ID, nil)
+			if err != nil {
+				log.Errorf(ctx, "db error getting blocks: %v", err)
+				return
+			}
+
+			// Initialize new blocks map.
+			wantedBlocks = make(map[string]struct{}, len(blocks))
+
+			// Once we've created (or tried to create)
+			// the required blocks, go through previous
+			// blocks and remove unwanted ones.
+			defer func() {
+				for _, prev := range prevBlocks {
+					username := prev.TargetAccount.Username
+					domain := prev.TargetAccount.Domain
+
+					_, wanted := wantedBlocks[username+"@"+domain]
+					if wanted {
+						// Leave this
+						// one alone.
+						continue
+					}
+
+					if _, errWithCode := p.BlockRemove(
+						ctx,
+						requester,
+						prev.TargetAccountID,
+					); errWithCode != nil {
+						log.Errorf(ctx, "could not unblock account: %v", errWithCode.Unwrap())
+						continue
+					}
+				}
+			}()
+		}
+
+		// Go through the blocks parsed from CSV
+		// file, and create / update each one.
+		for _, block := range blocks {
+			var (
+				// Username of the target.
+				username = block.TargetAccount.Username
+
+				// Domain of the target.
+				// Empty for our domain.
+				domain = block.TargetAccount.Domain
+			)
+
+			if overwrite {
+				// We'll be overwriting, so store
+				// this new block in our handy map.
+				wantedBlocks[username+"@"+domain] = struct{}{}
+			}
+
+			// Get the target account, dereferencing it if necessary.
+			targetAcct, _, err := p.federator.Dereferencer.GetAccountByUsernameDomain(
+				ctx,
+				// Provide empty request user to use the
+				// instance account to deref the account.
+				//
+				// It's pointless to make lots of calls
+				// to a remote from an account that's about
+				// to block that account.
+				"",
+				username,
+				domain,
+			)
+			if err != nil {
+				log.Errorf(ctx, "could not retrieve account: %v", err)
+				continue
+			}
+
+			// Use the processor's BlockCreate function
+			// to create or update the block. This takes
+			// account of existing blocks, and also sends
+			// the block to the FromClientAPI processor.
+			if _, errWithCode := p.BlockCreate(
+				ctx,
+				requester,
+				targetAcct.ID,
+			); errWithCode != nil {
+				log.Errorf(ctx, "could not block account: %v", errWithCode.Unwrap())
+				continue
+			}
+		}
+	}
+}