diff --git a/internal/distributor/distributor.go b/internal/distributor/distributor.go new file mode 100644 index 0000000..9cfe9be --- /dev/null +++ b/internal/distributor/distributor.go @@ -0,0 +1,96 @@ +/* + 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 . +*/ + +package distributor + +import ( + "github.com/go-fed/activity/pub" + "github.com/sirupsen/logrus" +) + +// Distributor should be passed to api modules (see internal/module/...). It is used for +// passing messages back and forth from the client API and the federating interface, via channels. +// It also contains logic for filtering which messages should end up where. +// It is designed to be used asynchronously: the client API and the federating API should just be able to +// fire messages into the distributor and not wait for a reply before proceeding with other work. This allows +// for clean distribution of messages without slowing down the client API and harming the user experience. +type Distributor interface { + // ClientAPIIn returns a channel for accepting messages that come from the gts client API. + ClientAPIIn() chan interface{} + // ClientAPIOut returns a channel for putting in messages that need to go to the gts client API. + ClientAPIOut() chan interface{} + // Start starts the Distributor, reading from its channels and passing messages back and forth. + Start() error + // Stop stops the distributor cleanly, finishing handling any remaining messages before closing down. + Stop() error +} + +// distributor just implements the Distributor interface +type distributor struct { + federator pub.FederatingActor + clientAPIIn chan interface{} + clientAPIOut chan interface{} + stop chan interface{} + log *logrus.Logger +} + +// New returns a new Distributor that uses the given federator and logger +func New(federator pub.FederatingActor, log *logrus.Logger) Distributor { + return &distributor{ + federator: federator, + clientAPIIn: make(chan interface{}, 100), + clientAPIOut: make(chan interface{}, 100), + stop: make(chan interface{}), + log: log, + } +} + +// ClientAPIIn returns a channel for accepting messages that come from the gts client API. +func (d *distributor) ClientAPIIn() chan interface{} { + return d.clientAPIIn +} + +// ClientAPIOut returns a channel for putting in messages that need to go to the gts client API. +func (d *distributor) ClientAPIOut() chan interface{} { + return d.clientAPIOut +} + +// Start starts the Distributor, reading from its channels and passing messages back and forth. +func (d *distributor) Start() error { + go func() { + DistLoop: + for { + select { + case clientMsgIn := <-d.clientAPIIn: + d.log.Infof("received clientMsgIn: %+v", clientMsgIn) + case clientMsgOut := <-d.clientAPIOut: + d.log.Infof("received clientMsgOut: %+v", clientMsgOut) + case <-d.stop: + break DistLoop + } + } + }() + return nil +} + +// Stop stops the distributor cleanly, finishing handling any remaining messages before closing down. +// TODO: empty message buffer properly before stopping otherwise we'll lose federating messages. +func (d *distributor) Stop() error { + close(d.stop) + return nil +}