Follows and relationships (#27)

* Follows -- create and undo, both remote and local
* Statuses -- federate new posts, including media, attachments, CWs and image descriptions.

9 files changed, 672 insertions, 68 deletions

diff --git a/internal/message/accountprocess.go b/internal/message/accountprocess.go
index a10f6d016..29fd55034 100644
--- a/internal/message/accountprocess.go
+++ b/internal/message/accountprocess.go
@@ -78,6 +78,15 @@ func (p *processor) AccountGet(authed *oauth.Auth, targetAccountID string) (*api
 		return nil, fmt.Errorf("db error: %s", err)
 	}
 
+	// lazily dereference things on the account if it hasn't been done yet
+	var requestingUsername string
+	if authed.Account != nil {
+		requestingUsername = authed.Account.Username
+	}
+	if err := p.dereferenceAccountFields(targetAccount, requestingUsername); err != nil {
+		p.log.WithField("func", "AccountGet").Debugf("dereferencing account: %s", err)
+	}
+
 	var mastoAccount *apimodel.Account
 	var err error
 	if authed.Account != nil && targetAccount.ID == authed.Account.ID {
@@ -285,6 +294,12 @@ func (p *processor) AccountFollowersGet(authed *oauth.Auth, targetAccountID stri
 			return nil, NewErrorInternalError(err)
 		}
 
+		// derefence account fields in case we haven't done it already
+		if err := p.dereferenceAccountFields(a, authed.Account.Username); err != nil {
+			// don't bail if we can't fetch them, we'll try another time
+			p.log.WithField("func", "AccountFollowersGet").Debugf("error dereferencing account fields: %s", err)
+		}
+
 		account, err := p.tc.AccountToMastoPublic(a)
 		if err != nil {
 			return nil, NewErrorInternalError(err)
@@ -293,3 +308,238 @@ func (p *processor) AccountFollowersGet(authed *oauth.Auth, targetAccountID stri
 	}
 	return accounts, nil
 }
+
+func (p *processor) AccountFollowingGet(authed *oauth.Auth, targetAccountID string) ([]apimodel.Account, ErrorWithCode) {
+	blocked, err := p.db.Blocked(authed.Account.ID, targetAccountID)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	if blocked {
+		return nil, NewErrorNotFound(fmt.Errorf("block exists between accounts"))
+	}
+
+	following := []gtsmodel.Follow{}
+	accounts := []apimodel.Account{}
+	if err := p.db.GetFollowingByAccountID(targetAccountID, &following); err != nil {
+		if _, ok := err.(db.ErrNoEntries); ok {
+			return accounts, nil
+		}
+		return nil, NewErrorInternalError(err)
+	}
+
+	for _, f := range following {
+		blocked, err := p.db.Blocked(authed.Account.ID, f.AccountID)
+		if err != nil {
+			return nil, NewErrorInternalError(err)
+		}
+		if blocked {
+			continue
+		}
+
+		a := &gtsmodel.Account{}
+		if err := p.db.GetByID(f.TargetAccountID, a); err != nil {
+			if _, ok := err.(db.ErrNoEntries); ok {
+				continue
+			}
+			return nil, NewErrorInternalError(err)
+		}
+
+		// derefence account fields in case we haven't done it already
+		if err := p.dereferenceAccountFields(a, authed.Account.Username); err != nil {
+			// don't bail if we can't fetch them, we'll try another time
+			p.log.WithField("func", "AccountFollowingGet").Debugf("error dereferencing account fields: %s", err)
+		}
+
+		account, err := p.tc.AccountToMastoPublic(a)
+		if err != nil {
+			return nil, NewErrorInternalError(err)
+		}
+		accounts = append(accounts, *account)
+	}
+	return accounts, nil
+}
+
+func (p *processor) AccountRelationshipGet(authed *oauth.Auth, targetAccountID string) (*apimodel.Relationship, ErrorWithCode) {
+	if authed == nil || authed.Account == nil {
+		return nil, NewErrorForbidden(errors.New("not authed"))
+	}
+
+	gtsR, err := p.db.GetRelationship(authed.Account.ID, targetAccountID)
+	if err != nil {
+		return nil, NewErrorInternalError(fmt.Errorf("error getting relationship: %s", err))
+	}
+
+	r, err := p.tc.RelationshipToMasto(gtsR)
+	if err != nil {
+		return nil, NewErrorInternalError(fmt.Errorf("error converting relationship: %s", err))
+	}
+
+	return r, nil
+}
+
+func (p *processor) AccountFollowCreate(authed *oauth.Auth, form *apimodel.AccountFollowRequest) (*apimodel.Relationship, ErrorWithCode) {
+	// if there's a block between the accounts we shouldn't create the request ofc
+	blocked, err := p.db.Blocked(authed.Account.ID, form.TargetAccountID)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+	if blocked {
+		return nil, NewErrorNotFound(fmt.Errorf("accountfollowcreate: block exists between accounts"))
+	}
+
+	// make sure the target account actually exists in our db
+	targetAcct := &gtsmodel.Account{}
+	if err := p.db.GetByID(form.TargetAccountID, targetAcct); err != nil {
+		if _, ok := err.(db.ErrNoEntries); ok {
+			return nil, NewErrorNotFound(fmt.Errorf("accountfollowcreate: account %s not found in the db: %s", form.TargetAccountID, err))
+		}
+	}
+
+	// check if a follow exists already
+	follows, err := p.db.Follows(authed.Account, targetAcct)
+	if err != nil {
+		return nil, NewErrorInternalError(fmt.Errorf("accountfollowcreate: error checking follow in db: %s", err))
+	}
+	if follows {
+		// already follows so just return the relationship
+		return p.AccountRelationshipGet(authed, form.TargetAccountID)
+	}
+
+	// check if a follow exists already
+	followRequested, err := p.db.FollowRequested(authed.Account, targetAcct)
+	if err != nil {
+		return nil, NewErrorInternalError(fmt.Errorf("accountfollowcreate: error checking follow request in db: %s", err))
+	}
+	if followRequested {
+		// already follow requested so just return the relationship
+		return p.AccountRelationshipGet(authed, form.TargetAccountID)
+	}
+
+	// make the follow request
+	fr := &gtsmodel.FollowRequest{
+		AccountID:       authed.Account.ID,
+		TargetAccountID: form.TargetAccountID,
+		ShowReblogs:     true,
+		URI:             util.GenerateURIForFollow(authed.Account.Username, p.config.Protocol, p.config.Host),
+		Notify:          false,
+	}
+	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(fr); err != nil {
+		return nil, 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(authed.Account.ID, form.TargetAccountID); err != nil {
+			return nil, NewErrorInternalError(fmt.Errorf("accountfollowcreate: error accepting folow request for local unlocked account: %s", err))
+		}
+		// return the new relationship
+		return p.AccountRelationshipGet(authed, form.TargetAccountID)
+	}
+
+	// otherwise we leave the follow request as it is and we handle the rest of the process asynchronously
+	p.fromClientAPI <- gtsmodel.FromClientAPI{
+		APObjectType:   gtsmodel.ActivityStreamsFollow,
+		APActivityType: gtsmodel.ActivityStreamsCreate,
+		GTSModel: &gtsmodel.Follow{
+			AccountID:       authed.Account.ID,
+			TargetAccountID: form.TargetAccountID,
+			URI:             fr.URI,
+		},
+		OriginAccount: authed.Account,
+		TargetAccount: targetAcct,
+	}
+
+	// return whatever relationship results from this
+	return p.AccountRelationshipGet(authed, form.TargetAccountID)
+}
+
+func (p *processor) AccountFollowRemove(authed *oauth.Auth, targetAccountID string) (*apimodel.Relationship, ErrorWithCode) {
+	// if there's a block between the accounts we shouldn't do anything
+	blocked, err := p.db.Blocked(authed.Account.ID, targetAccountID)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+	if blocked {
+		return nil, NewErrorNotFound(fmt.Errorf("AccountFollowRemove: block exists between accounts"))
+	}
+
+	// make sure the target account actually exists in our db
+	targetAcct := &gtsmodel.Account{}
+	if err := p.db.GetByID(targetAccountID, targetAcct); err != nil {
+		if _, ok := err.(db.ErrNoEntries); ok {
+			return nil, 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([]db.Where{
+		{Key: "account_id", Value: authed.Account.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, fr); err == nil {
+		frURI = fr.URI
+		if err := p.db.DeleteByID(fr.ID, fr); err != nil {
+			return nil, 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([]db.Where{
+		{Key: "account_id", Value: authed.Account.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, f); err == nil {
+		fURI = f.URI
+		if err := p.db.DeleteByID(f.ID, f); err != nil {
+			return nil, 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.fromClientAPI <- gtsmodel.FromClientAPI{
+			APObjectType:   gtsmodel.ActivityStreamsFollow,
+			APActivityType: gtsmodel.ActivityStreamsUndo,
+			GTSModel: &gtsmodel.Follow{
+				AccountID:       authed.Account.ID,
+				TargetAccountID: targetAccountID,
+				URI:             frURI,
+			},
+			OriginAccount: authed.Account,
+			TargetAccount: targetAcct,
+		}
+	}
+
+	// follow status changed so send the UNDO activity to the channel for async processing
+	if fChanged {
+		p.fromClientAPI <- gtsmodel.FromClientAPI{
+			APObjectType:   gtsmodel.ActivityStreamsFollow,
+			APActivityType: gtsmodel.ActivityStreamsUndo,
+			GTSModel: &gtsmodel.Follow{
+				AccountID:       authed.Account.ID,
+				TargetAccountID: targetAccountID,
+				URI:             fURI,
+			},
+			OriginAccount: authed.Account,
+			TargetAccount: targetAcct,
+		}
+	}
+
+	// return whatever relationship results from all this
+	return p.AccountRelationshipGet(authed, targetAccountID)
+}
diff --git a/internal/message/fediprocess.go b/internal/message/fediprocess.go
index 3c7c30e27..eb6e8b6d6 100644
--- a/internal/message/fediprocess.go
+++ b/internal/message/fediprocess.go
@@ -22,6 +22,7 @@ import (
 	"context"
 	"fmt"
 	"net/http"
+	"net/url"
 
 	"github.com/go-fed/activity/streams"
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
@@ -46,7 +47,7 @@ func (p *processor) authenticateAndDereferenceFediRequest(username string, r *ht
 	// we might already have an entry for this account so check that first
 	requestingAccount := &gtsmodel.Account{}
 
-	err = p.db.GetWhere("uri", requestingAccountURI.String(), requestingAccount)
+	err = p.db.GetWhere([]db.Where{{Key: "uri", Value: requestingAccountURI.String()}}, requestingAccount)
 	if err == nil {
 		// we do have it yay, return it
 		return requestingAccount, nil
@@ -122,6 +123,89 @@ func (p *processor) GetFediUser(requestedUsername string, request *http.Request)
 	return data, nil
 }
 
+func (p *processor) GetFediFollowers(requestedUsername string, request *http.Request) (interface{}, ErrorWithCode) {
+	// get the account the request is referring to
+	requestedAccount := &gtsmodel.Account{}
+	if err := p.db.GetLocalAccountByUsername(requestedUsername, requestedAccount); err != nil {
+		return nil, NewErrorNotFound(fmt.Errorf("database error getting account with username %s: %s", requestedUsername, err))
+	}
+
+	// authenticate the request
+	requestingAccount, err := p.authenticateAndDereferenceFediRequest(requestedUsername, request)
+	if err != nil {
+		return nil, NewErrorNotAuthorized(err)
+	}
+
+	blocked, err := p.db.Blocked(requestedAccount.ID, requestingAccount.ID)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	if blocked {
+		return nil, NewErrorNotAuthorized(fmt.Errorf("block exists between accounts %s and %s", requestedAccount.ID, requestingAccount.ID))
+	}
+
+	requestedAccountURI, err := url.Parse(requestedAccount.URI)
+	if err != nil {
+		return nil, NewErrorInternalError(fmt.Errorf("error parsing url %s: %s", requestedAccount.URI, err))
+	}
+
+	requestedFollowers, err := p.federator.FederatingDB().Followers(context.Background(), requestedAccountURI)
+	if err != nil {
+		return nil, NewErrorInternalError(fmt.Errorf("error fetching followers for uri %s: %s", requestedAccountURI.String(), err))
+	}
+
+	data, err := streams.Serialize(requestedFollowers)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	return data, nil
+}
+
+func (p *processor) GetFediStatus(requestedUsername string, requestedStatusID string, request *http.Request) (interface{}, ErrorWithCode) {
+		// get the account the request is referring to
+		requestedAccount := &gtsmodel.Account{}
+		if err := p.db.GetLocalAccountByUsername(requestedUsername, requestedAccount); err != nil {
+			return nil, NewErrorNotFound(fmt.Errorf("database error getting account with username %s: %s", requestedUsername, err))
+		}
+
+		// authenticate the request
+		requestingAccount, err := p.authenticateAndDereferenceFediRequest(requestedUsername, request)
+		if err != nil {
+			return nil, NewErrorNotAuthorized(err)
+		}
+
+		blocked, err := p.db.Blocked(requestedAccount.ID, requestingAccount.ID)
+		if err != nil {
+			return nil, NewErrorInternalError(err)
+		}
+
+		if blocked {
+			return nil, NewErrorNotAuthorized(fmt.Errorf("block exists between accounts %s and %s", requestedAccount.ID, requestingAccount.ID))
+		}
+
+		s := &gtsmodel.Status{}
+		if err := p.db.GetWhere([]db.Where{
+			{Key: "id", Value: requestedStatusID},
+			{Key: "account_id", Value: requestedAccount.ID},
+		}, s); err != nil {
+			return nil, NewErrorNotFound(fmt.Errorf("database error getting status with id %s and account id %s: %s", requestedStatusID, requestedAccount.ID, err))
+		}
+
+		asStatus, err := p.tc.StatusToAS(s)
+		if err != nil {
+			return nil, NewErrorInternalError(err)
+		}
+
+		data, err := streams.Serialize(asStatus)
+		if err != nil {
+			return nil, NewErrorInternalError(err)
+		}
+
+		return data, nil
+}
+
 func (p *processor) GetWebfingerAccount(requestedUsername string, request *http.Request) (*apimodel.WebfingerAccountResponse, ErrorWithCode) {
 	// get the account the request is referring to
 	requestedAccount := &gtsmodel.Account{}
diff --git a/internal/message/fromclientapiprocess.go b/internal/message/fromclientapiprocess.go
index 1a12216e7..e91bd6ce4 100644
--- a/internal/message/fromclientapiprocess.go
+++ b/internal/message/fromclientapiprocess.go
@@ -19,55 +19,198 @@
 package message
 
 import (
+	"context"
 	"errors"
 	"fmt"
+	"net/url"
 
+	"github.com/go-fed/activity/streams"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 )
 
 func (p *processor) processFromClientAPI(clientMsg gtsmodel.FromClientAPI) error {
-	switch clientMsg.APObjectType {
-	case gtsmodel.ActivityStreamsNote:
-		status, ok := clientMsg.GTSModel.(*gtsmodel.Status)
-		if !ok {
-			return errors.New("note was not parseable as *gtsmodel.Status")
-		}
+	switch clientMsg.APActivityType {
+	case gtsmodel.ActivityStreamsCreate:
+		// CREATE
+		switch clientMsg.APObjectType {
+		case gtsmodel.ActivityStreamsNote:
+			// CREATE NOTE
+			status, ok := clientMsg.GTSModel.(*gtsmodel.Status)
+			if !ok {
+				return errors.New("note was not parseable as *gtsmodel.Status")
+			}
 
-		if err := p.notifyStatus(status); err != nil {
-			return err
-		}
+			if err := p.notifyStatus(status); err != nil {
+				return err
+			}
+
+			if status.VisibilityAdvanced.Federated {
+				return p.federateStatus(status)
+			}
+			return nil
+		case gtsmodel.ActivityStreamsFollow:
+			// CREATE FOLLOW (request)
+			follow, ok := clientMsg.GTSModel.(*gtsmodel.Follow)
+			if !ok {
+				return errors.New("follow was not parseable as *gtsmodel.Follow")
+			}
+
+			if err := p.notifyFollow(follow); err != nil {
+				return err
+			}
 
-		if status.VisibilityAdvanced.Federated {
-			return p.federateStatus(status)
+			return p.federateFollow(follow, clientMsg.OriginAccount, clientMsg.TargetAccount)
+		}
+	case gtsmodel.ActivityStreamsUpdate:
+		// UPDATE
+	case gtsmodel.ActivityStreamsAccept:
+		// ACCEPT
+		switch clientMsg.APObjectType {
+		case gtsmodel.ActivityStreamsFollow:
+			// ACCEPT FOLLOW
+			follow, ok := clientMsg.GTSModel.(*gtsmodel.Follow)
+			if !ok {
+				return errors.New("accept was not parseable as *gtsmodel.Follow")
+			}
+			return p.federateAcceptFollowRequest(follow, clientMsg.OriginAccount, clientMsg.TargetAccount)
+		}
+	case gtsmodel.ActivityStreamsUndo:
+		// UNDO
+		switch clientMsg.APObjectType {
+		case gtsmodel.ActivityStreamsFollow:
+			// UNDO FOLLOW
+			follow, ok := clientMsg.GTSModel.(*gtsmodel.Follow)
+			if !ok {
+				return errors.New("undo was not parseable as *gtsmodel.Follow")
+			}
+			return p.federateUnfollow(follow, clientMsg.OriginAccount, clientMsg.TargetAccount)
 		}
-		return nil
 	}
-	return fmt.Errorf("message type unprocessable: %+v", clientMsg)
+	return nil
 }
 
 func (p *processor) federateStatus(status *gtsmodel.Status) error {
-	// // derive the sending account -- it might be attached to the status already
-	// sendingAcct := &gtsmodel.Account{}
-	// if status.GTSAccount != nil {
-	// 	sendingAcct = status.GTSAccount
-	// } else {
-	// 	// it wasn't attached so get it from the db instead
-	// 	if err := p.db.GetByID(status.AccountID, sendingAcct); err != nil {
-	// 		return err
-	// 	}
-	// }
-
-	// outboxURI, err := url.Parse(sendingAcct.OutboxURI)
-	// if err != nil {
-	// 	return err
-	// }
-
-	// // convert the status to AS format Note
-	// note, err := p.tc.StatusToAS(status)
-	// if err != nil {
-	// 	return err
-	// }
-
-	// _, err = p.federator.FederatingActor().Send(context.Background(), outboxURI, note)
-	return nil
+	asStatus, err := p.tc.StatusToAS(status)
+	if err != nil {
+		return fmt.Errorf("federateStatus: error converting status to as format: %s", err)
+	}
+
+	outboxIRI, err := url.Parse(status.GTSAccount.OutboxURI)
+	if err != nil {
+		return fmt.Errorf("federateStatus: error parsing outboxURI %s: %s", status.GTSAccount.OutboxURI, err)
+	}
+
+	_, err = p.federator.FederatingActor().Send(context.Background(), outboxIRI, asStatus)
+	return err
+}
+
+func (p *processor) federateFollow(follow *gtsmodel.Follow, originAccount *gtsmodel.Account, targetAccount *gtsmodel.Account) error {
+	// if both accounts are local there's nothing to do here
+	if originAccount.Domain == "" && targetAccount.Domain == "" {
+		return nil
+	}
+
+	asFollow, err := p.tc.FollowToAS(follow, originAccount, targetAccount)
+	if err != nil {
+		return fmt.Errorf("federateFollow: error converting follow to as format: %s", err)
+	}
+
+	outboxIRI, err := url.Parse(originAccount.OutboxURI)
+	if err != nil {
+		return fmt.Errorf("federateFollow: error parsing outboxURI %s: %s", originAccount.OutboxURI, err)
+	}
+
+	_, err = p.federator.FederatingActor().Send(context.Background(), outboxIRI, asFollow)
+	return err
+}
+
+func (p *processor) federateUnfollow(follow *gtsmodel.Follow, originAccount *gtsmodel.Account, targetAccount *gtsmodel.Account) error {
+	// if both accounts are local there's nothing to do here
+	if originAccount.Domain == "" && targetAccount.Domain == "" {
+		return nil
+	}
+
+	// recreate the follow
+	asFollow, err := p.tc.FollowToAS(follow, originAccount, targetAccount)
+	if err != nil {
+		return fmt.Errorf("federateUnfollow: error converting follow to as format: %s", err)
+	}
+
+	targetAccountURI, err := url.Parse(targetAccount.URI)
+	if err != nil {
+		return fmt.Errorf("error parsing uri %s: %s", targetAccount.URI, err)
+	}
+
+	// create an Undo and set the appropriate actor on it
+	undo := streams.NewActivityStreamsUndo()
+	undo.SetActivityStreamsActor(asFollow.GetActivityStreamsActor())
+
+	// Set the recreated follow as the 'object' property.
+	undoObject := streams.NewActivityStreamsObjectProperty()
+	undoObject.AppendActivityStreamsFollow(asFollow)
+	undo.SetActivityStreamsObject(undoObject)
+
+	// Set the To of the undo as the target of the recreated follow
+	undoTo := streams.NewActivityStreamsToProperty()
+	undoTo.AppendIRI(targetAccountURI)
+	undo.SetActivityStreamsTo(undoTo)
+
+	outboxIRI, err := url.Parse(originAccount.OutboxURI)
+	if err != nil {
+		return fmt.Errorf("federateUnfollow: error parsing outboxURI %s: %s", originAccount.OutboxURI, err)
+	}
+
+	// send off the Undo
+	_, err = p.federator.FederatingActor().Send(context.Background(), outboxIRI, undo)
+	return err
+}
+
+func (p *processor) federateAcceptFollowRequest(follow *gtsmodel.Follow, originAccount *gtsmodel.Account, targetAccount *gtsmodel.Account) error {
+	// if both accounts are local there's nothing to do here
+	if originAccount.Domain == "" && targetAccount.Domain == "" {
+		return nil
+	}
+
+	// recreate the AS follow
+	asFollow, err := p.tc.FollowToAS(follow, originAccount, targetAccount)
+	if err != nil {
+		return fmt.Errorf("federateUnfollow: error converting follow to as format: %s", err)
+	}
+
+	acceptingAccountURI, err := url.Parse(targetAccount.URI)
+	if err != nil {
+		return fmt.Errorf("error parsing uri %s: %s", targetAccount.URI, err)
+	}
+
+	requestingAccountURI, err := url.Parse(originAccount.URI)
+	if err != nil {
+		return fmt.Errorf("error parsing uri %s: %s", targetAccount.URI, err)
+	}
+
+	// create an Accept
+	accept := streams.NewActivityStreamsAccept()
+
+	// set the accepting actor on it
+	acceptActorProp := streams.NewActivityStreamsActorProperty()
+	acceptActorProp.AppendIRI(acceptingAccountURI)
+	accept.SetActivityStreamsActor(acceptActorProp)
+
+	// Set the recreated follow as the 'object' property.
+	acceptObject := streams.NewActivityStreamsObjectProperty()
+	acceptObject.AppendActivityStreamsFollow(asFollow)
+	accept.SetActivityStreamsObject(acceptObject)
+
+	// Set the To of the accept as the originator of the follow
+	acceptTo := streams.NewActivityStreamsToProperty()
+	acceptTo.AppendIRI(requestingAccountURI)
+	accept.SetActivityStreamsTo(acceptTo)
+
+	outboxIRI, err := url.Parse(targetAccount.OutboxURI)
+	if err != nil {
+		return fmt.Errorf("federateAcceptFollowRequest: error parsing outboxURI %s: %s", originAccount.OutboxURI, err)
+	}
+
+	// send off the accept using the accepter's outbox
+	_, err = p.federator.FederatingActor().Send(context.Background(), outboxIRI, accept)
+	return err
 }
diff --git a/internal/message/fromcommonprocess.go b/internal/message/fromcommonprocess.go
index 14f145df9..d557b7962 100644
--- a/internal/message/fromcommonprocess.go
+++ b/internal/message/fromcommonprocess.go
@@ -23,3 +23,7 @@ import "github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 func (p *processor) notifyStatus(status *gtsmodel.Status) error {
 	return nil
 }
+
+func (p *processor) notifyFollow(follow *gtsmodel.Follow) error {
+   return nil
+}
diff --git a/internal/message/fromfederatorprocess.go b/internal/message/fromfederatorprocess.go
index 2dd8e9e3b..ffaa1b93b 100644
--- a/internal/message/fromfederatorprocess.go
+++ b/internal/message/fromfederatorprocess.go
@@ -38,24 +38,60 @@ func (p *processor) processFromFederator(federatorMsg gtsmodel.FromFederator) er
 
 	l.Debug("entering function PROCESS FROM FEDERATOR")
 
-	switch federatorMsg.APObjectType {
-	case gtsmodel.ActivityStreamsNote:
+	switch federatorMsg.APActivityType {
+	case gtsmodel.ActivityStreamsCreate:
+		// CREATE
+		switch federatorMsg.APObjectType {
+		case gtsmodel.ActivityStreamsNote:
+			// CREATE A STATUS
+			incomingStatus, ok := federatorMsg.GTSModel.(*gtsmodel.Status)
+			if !ok {
+				return errors.New("note was not parseable as *gtsmodel.Status")
+			}
 
-		incomingStatus, ok := federatorMsg.GTSModel.(*gtsmodel.Status)
-		if !ok {
-			return errors.New("note was not parseable as *gtsmodel.Status")
-		}
+			l.Debug("will now derefence incoming status")
+			if err := p.dereferenceStatusFields(incomingStatus); err != nil {
+				return fmt.Errorf("error dereferencing status from federator: %s", err)
+			}
+			if err := p.db.UpdateByID(incomingStatus.ID, incomingStatus); err != nil {
+				return fmt.Errorf("error updating dereferenced status in the db: %s", err)
+			}
 
-		l.Debug("will now derefence incoming status")
-		if err := p.dereferenceStatusFields(incomingStatus); err != nil {
-			return fmt.Errorf("error dereferencing status from federator: %s", err)
-		}
-		if err := p.db.UpdateByID(incomingStatus.ID, incomingStatus); err != nil {
-			return fmt.Errorf("error updating dereferenced status in the db: %s", err)
+			if err := p.notifyStatus(incomingStatus); err != nil {
+				return err
+			}
+		case gtsmodel.ActivityStreamsProfile:
+			// CREATE AN ACCOUNT
+			incomingAccount, ok := federatorMsg.GTSModel.(*gtsmodel.Account)
+			if !ok {
+				return errors.New("profile was not parseable as *gtsmodel.Account")
+			}
+
+			l.Debug("will now derefence incoming account")
+			if err := p.dereferenceAccountFields(incomingAccount, ""); err != nil {
+				return fmt.Errorf("error dereferencing account from federator: %s", err)
+			}
+			if err := p.db.UpdateByID(incomingAccount.ID, incomingAccount); err != nil {
+				return fmt.Errorf("error updating dereferenced account in the db: %s", err)
+			}
 		}
+	case gtsmodel.ActivityStreamsUpdate:
+		// UPDATE
+		switch federatorMsg.APObjectType {
+		case gtsmodel.ActivityStreamsProfile:
+			// UPDATE AN ACCOUNT
+			incomingAccount, ok := federatorMsg.GTSModel.(*gtsmodel.Account)
+			if !ok {
+				return errors.New("profile was not parseable as *gtsmodel.Account")
+			}
 
-		if err := p.notifyStatus(incomingStatus); err != nil {
-			return err
+			l.Debug("will now derefence incoming account")
+			if err := p.dereferenceAccountFields(incomingAccount, ""); err != nil {
+				return fmt.Errorf("error dereferencing account from federator: %s", err)
+			}
+			if err := p.db.UpdateByID(incomingAccount.ID, incomingAccount); err != nil {
+				return fmt.Errorf("error updating dereferenced account in the db: %s", err)
+			}
 		}
 	}
 
@@ -121,7 +157,7 @@ func (p *processor) dereferenceStatusFields(status *gtsmodel.Status) error {
 
 		// it might have been processed elsewhere so check first if it's already in the database or not
 		maybeAttachment := &gtsmodel.MediaAttachment{}
-		err := p.db.GetWhere("remote_url", a.RemoteURL, maybeAttachment)
+		err := p.db.GetWhere([]db.Where{{Key: "remote_url", Value: a.RemoteURL}}, maybeAttachment)
 		if err == nil {
 			// we already have it in the db, dereferenced, no need to do it again
 			l.Debugf("attachment already exists with id %s", maybeAttachment.ID)
@@ -170,7 +206,7 @@ func (p *processor) dereferenceStatusFields(status *gtsmodel.Status) error {
 		m.OriginAccountURI = status.GTSAccount.URI
 
 		targetAccount := &gtsmodel.Account{}
-		if err := p.db.GetWhere("uri", uri.String(), targetAccount); err != nil {
+		if err := p.db.GetWhere([]db.Where{{Key: "uri", Value: uri.String()}}, targetAccount); err != nil {
 			// proper error
 			if _, ok := err.(db.ErrNoEntries); !ok {
 				return fmt.Errorf("db error checking for account with uri %s", uri.String())
@@ -206,3 +242,27 @@ func (p *processor) dereferenceStatusFields(status *gtsmodel.Status) error {
 
 	return nil
 }
+
+func (p *processor) dereferenceAccountFields(account *gtsmodel.Account, requestingUsername string) error {
+	l := p.log.WithFields(logrus.Fields{
+		"func":               "dereferenceAccountFields",
+		"requestingUsername": requestingUsername,
+	})
+
+	t, err := p.federator.GetTransportForUser(requestingUsername)
+	if err != nil {
+		return fmt.Errorf("error getting transport for user: %s", err)
+	}
+
+	// fetch the header and avatar
+	if err := p.fetchHeaderAndAviForAccount(account, t); err != nil {
+		// if this doesn't work, just skip it -- we can do it later
+		l.Debugf("error fetching header/avi for account: %s", err)
+	}
+
+	if err := p.db.UpdateByID(account.ID, account); err != nil {
+		return fmt.Errorf("error updating account in database: %s", err)
+	}
+
+	return nil
+}
diff --git a/internal/message/frprocess.go b/internal/message/frprocess.go
index cc3838598..fd64b4c50 100644
--- a/internal/message/frprocess.go
+++ b/internal/message/frprocess.go
@@ -48,11 +48,28 @@ func (p *processor) FollowRequestsGet(auth *oauth.Auth) ([]apimodel.Account, Err
 	return accts, nil
 }
 
-func (p *processor) FollowRequestAccept(auth *oauth.Auth, accountID string) ErrorWithCode {
-	if err := p.db.AcceptFollowRequest(accountID, auth.Account.ID); err != nil {
-		return NewErrorNotFound(err)
+func (p *processor) FollowRequestAccept(auth *oauth.Auth, accountID string) (*apimodel.Relationship, ErrorWithCode) {
+	follow, err := p.db.AcceptFollowRequest(accountID, auth.Account.ID)
+	if err != nil {
+		return nil, NewErrorNotFound(err)
 	}
-	return nil
+
+	p.fromClientAPI <- gtsmodel.FromClientAPI{
+		APActivityType: gtsmodel.ActivityStreamsAccept,
+		GTSModel: follow,
+	}
+
+	gtsR, err := p.db.GetRelationship(auth.Account.ID, accountID)
+	if err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	r, err := p.tc.RelationshipToMasto(gtsR)
+	if  err != nil {
+		return nil, NewErrorInternalError(err)
+	}
+
+	return r, nil
 }
 
 func (p *processor) FollowRequestDeny(auth *oauth.Auth) ErrorWithCode {
diff --git a/internal/message/instanceprocess.go b/internal/message/instanceprocess.go
index 05ea103fd..f544fbf30 100644
--- a/internal/message/instanceprocess.go
+++ b/internal/message/instanceprocess.go
@@ -22,12 +22,13 @@ import (
 	"fmt"
 
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 )
 
 func (p *processor) InstanceGet(domain string) (*apimodel.Instance, ErrorWithCode) {
 	i := &gtsmodel.Instance{}
-	if err := p.db.GetWhere("domain", domain, i); err != nil {
+	if err := p.db.GetWhere([]db.Where{{Key: "domain", Value: domain}}, i); err != nil {
 		return nil, NewErrorInternalError(fmt.Errorf("db error fetching instance %s: %s", p.config.Host, err))
 	}
 
diff --git a/internal/message/processor.go b/internal/message/processor.go
index c9ba5f858..e9888d647 100644
--- a/internal/message/processor.go
+++ b/internal/message/processor.go
@@ -71,8 +71,16 @@ type Processor interface {
 	// AccountStatusesGet fetches a number of statuses (in time descending order) from the given account, filtered by visibility for
 	// the account given in authed.
 	AccountStatusesGet(authed *oauth.Auth, targetAccountID string, limit int, excludeReplies bool, maxID string, pinned bool, mediaOnly bool) ([]apimodel.Status, ErrorWithCode)
-	// AccountFollowersGet
+	// AccountFollowersGet fetches a list of the target account's followers.
 	AccountFollowersGet(authed *oauth.Auth, targetAccountID string) ([]apimodel.Account, ErrorWithCode)
+	// AccountFollowingGet fetches a list of the accounts that target account is following.
+	AccountFollowingGet(authed *oauth.Auth, targetAccountID string) ([]apimodel.Account, ErrorWithCode)
+	// AccountRelationshipGet returns a relationship model describing the relationship of the targetAccount to the Authed account.
+	AccountRelationshipGet(authed *oauth.Auth, targetAccountID string) (*apimodel.Relationship, ErrorWithCode)
+	// AccountFollowCreate handles a follow request to an account, either remote or local.
+	AccountFollowCreate(authed *oauth.Auth, form *apimodel.AccountFollowRequest) (*apimodel.Relationship, ErrorWithCode)
+	// AccountFollowRemove handles the removal of a follow/follow request to an account, either remote or local.
+	AccountFollowRemove(authed *oauth.Auth, targetAccountID string) (*apimodel.Relationship, ErrorWithCode)
 
 	// AdminEmojiCreate handles the creation of a new instance emoji by an admin, using the given form.
 	AdminEmojiCreate(authed *oauth.Auth, form *apimodel.EmojiCreateRequest) (*apimodel.Emoji, error)
@@ -86,7 +94,7 @@ type Processor interface {
 	// FollowRequestsGet handles the getting of the authed account's incoming follow requests
 	FollowRequestsGet(auth *oauth.Auth) ([]apimodel.Account, ErrorWithCode)
 	// FollowRequestAccept handles the acceptance of a follow request from the given account ID
-	FollowRequestAccept(auth *oauth.Auth, accountID string) ErrorWithCode
+	FollowRequestAccept(auth *oauth.Auth, accountID string) (*apimodel.Relationship, ErrorWithCode)
 
 	// InstanceGet retrieves instance information for serving at api/v1/instance
 	InstanceGet(domain string) (*apimodel.Instance, ErrorWithCode)
@@ -125,6 +133,14 @@ type Processor interface {
 	// before returning a JSON serializable interface to the caller.
 	GetFediUser(requestedUsername string, request *http.Request) (interface{}, ErrorWithCode)
 
+	// GetFediFollowers handles the getting of a fedi/activitypub representation of a user/account's followers, performing appropriate
+	// authentication before returning a JSON serializable interface to the caller.
+	GetFediFollowers(requestedUsername string, request *http.Request) (interface{}, ErrorWithCode)
+
+	// GetFediStatus handles the getting of a fedi/activitypub representation of a particular status, performing appropriate
+	// authentication before returning a JSON serializable interface to the caller.
+	GetFediStatus(requestedUsername string, requestedStatusID string, request *http.Request) (interface{}, ErrorWithCode)
+
 	// GetWebfingerAccount handles the GET for a webfinger resource. Most commonly, it will be used for returning account lookups.
 	GetWebfingerAccount(requestedUsername string, request *http.Request) (*apimodel.WebfingerAccountResponse, ErrorWithCode)
 
@@ -200,15 +216,11 @@ func (p *processor) Start() error {
 	DistLoop:
 		for {
 			select {
-			// case clientMsg := <-p.toClientAPI:
-			// 	p.log.Infof("received message TO client API: %+v", clientMsg)
 			case clientMsg := <-p.fromClientAPI:
 				p.log.Infof("received message FROM client API: %+v", clientMsg)
 				if err := p.processFromClientAPI(clientMsg); err != nil {
 					p.log.Error(err)
 				}
-			// case federatorMsg := <-p.toFederator:
-			// 	p.log.Infof("received message TO federator: %+v", federatorMsg)
 			case federatorMsg := <-p.fromFederator:
 				p.log.Infof("received message FROM federator: %+v", federatorMsg)
 				if err := p.processFromFederator(federatorMsg); err != nil {
diff --git a/internal/message/processorutil.go b/internal/message/processorutil.go
index 676635a51..67c96abe0 100644
--- a/internal/message/processorutil.go
+++ b/internal/message/processorutil.go
@@ -29,6 +29,7 @@ import (
 	"github.com/superseriousbusiness/gotosocial/internal/db"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 	"github.com/superseriousbusiness/gotosocial/internal/media"
+	"github.com/superseriousbusiness/gotosocial/internal/transport"
 	"github.com/superseriousbusiness/gotosocial/internal/util"
 )
 
@@ -205,7 +206,7 @@ func (p *processor) processMentions(form *apimodel.AdvancedStatusCreateForm, acc
 		if err := p.db.Put(menchie); err != nil {
 			return fmt.Errorf("error putting mentions in db: %s", err)
 		}
-		menchies = append(menchies, menchie.TargetAccountID)
+		menchies = append(menchies, menchie.ID)
 	}
 	// add full populated gts menchies to the status for passing them around conveniently
 	status.GTSMentions = gtsMenchies
@@ -280,7 +281,7 @@ func (p *processor) updateAccountAvatar(avatar *multipart.FileHeader, accountID
 	}
 
 	// do the setting
-	avatarInfo, err := p.mediaHandler.ProcessHeaderOrAvatar(buf.Bytes(), accountID, media.Avatar)
+	avatarInfo, err := p.mediaHandler.ProcessHeaderOrAvatar(buf.Bytes(), accountID, media.Avatar, "")
 	if err != nil {
 		return nil, fmt.Errorf("error processing avatar: %s", err)
 	}
@@ -313,10 +314,42 @@ func (p *processor) updateAccountHeader(header *multipart.FileHeader, accountID
 	}
 
 	// do the setting
-	headerInfo, err := p.mediaHandler.ProcessHeaderOrAvatar(buf.Bytes(), accountID, media.Header)
+	headerInfo, err := p.mediaHandler.ProcessHeaderOrAvatar(buf.Bytes(), accountID, media.Header, "")
 	if err != nil {
 		return nil, fmt.Errorf("error processing header: %s", err)
 	}
 
 	return headerInfo, f.Close()
 }
+
+// fetchHeaderAndAviForAccount fetches the header and avatar for a remote account, using a transport
+// on behalf of requestingUsername.
+//
+// targetAccount's AvatarMediaAttachmentID and HeaderMediaAttachmentID will be updated as necessary.
+//
+// SIDE EFFECTS: remote header and avatar will be stored in local storage, and the database will be updated
+// to reflect the creation of these new attachments.
+func (p *processor) fetchHeaderAndAviForAccount(targetAccount *gtsmodel.Account, t transport.Transport) error {
+	if targetAccount.AvatarRemoteURL != "" && targetAccount.AvatarMediaAttachmentID == "" {
+		a, err := p.mediaHandler.ProcessRemoteHeaderOrAvatar(t, &gtsmodel.MediaAttachment{
+			RemoteURL: targetAccount.AvatarRemoteURL,
+			Avatar:    true,
+		}, targetAccount.ID)
+		if err != nil {
+			return fmt.Errorf("error processing avatar for user: %s", err)
+		}
+		targetAccount.AvatarMediaAttachmentID = a.ID
+	}
+
+	if targetAccount.HeaderRemoteURL != "" && targetAccount.HeaderMediaAttachmentID == "" {
+		a, err := p.mediaHandler.ProcessRemoteHeaderOrAvatar(t, &gtsmodel.MediaAttachment{
+			RemoteURL: targetAccount.HeaderRemoteURL,
+			Header:    true,
+		}, targetAccount.ID)
+		if err != nil {
+			return fmt.Errorf("error processing header for user: %s", err)
+		}
+		targetAccount.HeaderMediaAttachmentID = a.ID
+	}
+	return nil
+}