Enable stricter linting with golangci-lint (#316)

* update golangci-lint

* add golangci config file w/ more linters

* correct issues flagged by stricter linters

* add more generous timeout for golangci-lint

* add some style + formatting guidelines

* move timeout to config file

* go fmt

7 files changed, 35 insertions, 20 deletions

diff --git a/internal/federation/authenticate.go b/internal/federation/authenticate.go
index eb0e675c3..fea5a765a 100644
--- a/internal/federation/authenticate.go
+++ b/internal/federation/authenticate.go
@@ -149,7 +149,7 @@ func (f *federator) AuthenticateFederatedRequest(ctx context.Context, requestedU
 	requestingPublicKeyID, err := url.Parse(verifier.KeyId())
 	if err != nil {
 		l.Debug("couldn't parse public key URL")
-		return nil, false, nil // couldn't parse the public key ID url
+		return nil, false, err // couldn't parse the public key ID url
 	}
 
 	requestingRemoteAccount := &gtsmodel.Account{}
diff --git a/internal/federation/dereferencing/thread.go b/internal/federation/dereferencing/thread.go
index 4912bc591..db1d336c6 100644
--- a/internal/federation/dereferencing/thread.go
+++ b/internal/federation/dereferencing/thread.go
@@ -172,7 +172,7 @@ pageLoop:
 		l.Debugf("dereferencing page %s", currentPageIRI)
 		nextPage, err := d.DereferenceCollectionPage(ctx, username, currentPageIRI)
 		if err != nil {
-			return nil
+			return err
 		}
 
 		// next items could be either a list of URLs or a list of statuses
@@ -188,19 +188,19 @@ pageLoop:
 			// We're looking for a url to feed to GetRemoteStatus.
 			// Items can be either an IRI, or a Note.
 			// If a note, we grab the ID from it and call it, rather than parsing the note.
-
 			var itemURI *url.URL
-			if iter.IsIRI() {
+			switch {
+			case iter.IsIRI():
 				// iri, easy
 				itemURI = iter.GetIRI()
-			} else if iter.IsActivityStreamsNote() {
+			case iter.IsActivityStreamsNote():
 				// note, get the id from it to use as iri
 				n := iter.GetActivityStreamsNote()
 				id := n.GetJSONLDId()
 				if id != nil && id.IsIRI() {
 					itemURI = id.GetIRI()
 				}
-			} else {
+			default:
 				// if it's not an iri or a note, we don't know how to process it
 				continue
 			}
@@ -211,7 +211,7 @@ pageLoop:
 			}
 
 			// we can confidently say now that we found something
-			foundReplies = foundReplies + 1
+			foundReplies++
 
 			// get the remote statusable and put it in the db
 			_, statusable, new, err := d.GetRemoteStatus(ctx, username, itemURI, false, false)
diff --git a/internal/federation/federatingdb/accept.go b/internal/federation/federatingdb/accept.go
index 1509b37bc..8efb29b53 100644
--- a/internal/federation/federatingdb/accept.go
+++ b/internal/federation/federatingdb/accept.go
@@ -97,9 +97,7 @@ func (f *federatingDB) Accept(ctx context.Context, accept vocab.ActivityStreamsA
 		if iter.GetType() == nil {
 			continue
 		}
-		switch iter.GetType().GetTypeName() {
-		// we have the whole object so we can figure out what we're accepting
-		case ap.ActivityFollow:
+		if iter.GetType().GetTypeName() == ap.ActivityFollow {
 			// ACCEPT FOLLOW
 			asFollow, ok := iter.GetType().(vocab.ActivityStreamsFollow)
 			if !ok {
diff --git a/internal/federation/federatingdb/lock.go b/internal/federation/federatingdb/lock.go
index 0d35f337f..22be6c793 100644
--- a/internal/federation/federatingdb/lock.go
+++ b/internal/federation/federatingdb/lock.go
@@ -24,6 +24,8 @@ import (
 	"net/url"
 	"sync"
 	"sync/atomic"
+
+	"github.com/sirupsen/logrus"
 )
 
 // Lock takes a lock for the object at the specified id. If an error
@@ -54,7 +56,10 @@ func (f *federatingDB) Lock(c context.Context, id *url.URL) error {
 	// Get mutex, or create new
 	mu, ok := f.locks[idStr]
 	if !ok {
-		mu = f.pool.Get().(*mutex)
+		mu, ok = f.pool.Get().(*mutex)
+		if !ok {
+			logrus.Panic("Lock: pool entry was not a *mutex")
+		}
 		f.locks[idStr] = mu
 	}
 
diff --git a/internal/federation/federatingdb/reject.go b/internal/federation/federatingdb/reject.go
index 2d8687ee9..15d4a87ae 100644
--- a/internal/federation/federatingdb/reject.go
+++ b/internal/federation/federatingdb/reject.go
@@ -90,9 +90,8 @@ func (f *federatingDB) Reject(ctx context.Context, reject vocab.ActivityStreamsR
 			continue
 		}
 
-		switch iter.GetType().GetTypeName() {
-		// we have the whole object so we can figure out what we're rejecting
-		case ap.ActivityFollow:
+		if iter.GetType().GetTypeName() == ap.ActivityFollow {
+			// we have the whole object so we can figure out what we're rejecting
 			// REJECT FOLLOW
 			asFollow, ok := iter.GetType().(vocab.ActivityStreamsFollow)
 			if !ok {
diff --git a/internal/federation/federatingdb/util.go b/internal/federation/federatingdb/util.go
index 87b85aed6..f35fbbb2d 100644
--- a/internal/federation/federatingdb/util.go
+++ b/internal/federation/federatingdb/util.go
@@ -308,17 +308,29 @@ func (f *federatingDB) collectIRIs(ctx context.Context, iris []*url.URL) (vocab.
 func extractFromCtx(ctx context.Context) (receivingAccount, requestingAccount *gtsmodel.Account, fromFederatorChan chan messages.FromFederator) {
 	receivingAccountI := ctx.Value(util.APReceivingAccount)
 	if receivingAccountI != nil {
-		receivingAccount = receivingAccountI.(*gtsmodel.Account)
+		var ok bool
+		receivingAccount, ok = receivingAccountI.(*gtsmodel.Account)
+		if !ok {
+			logrus.Panicf("extractFromCtx: context entry with key %s could not be asserted to *gtsmodel.Account", util.APReceivingAccount)
+		}
 	}
 
 	requestingAcctI := ctx.Value(util.APRequestingAccount)
 	if requestingAcctI != nil {
-		requestingAccount = requestingAcctI.(*gtsmodel.Account)
+		var ok bool
+		requestingAccount, ok = requestingAcctI.(*gtsmodel.Account)
+		if !ok {
+			logrus.Panicf("extractFromCtx: context entry with key %s could not be asserted to *gtsmodel.Account", util.APRequestingAccount)
+		}
 	}
 
 	fromFederatorChanI := ctx.Value(util.APFromFederatorChanKey)
 	if fromFederatorChanI != nil {
-		fromFederatorChan = fromFederatorChanI.(chan messages.FromFederator)
+		var ok bool
+		fromFederatorChan, ok = fromFederatorChanI.(chan messages.FromFederator)
+		if !ok {
+			logrus.Panicf("extractFromCtx: context entry with key %s could not be asserted to chan messages.FromFederator", util.APFromFederatorChanKey)
+		}
 	}
 
 	return
diff --git a/internal/federation/transport.go b/internal/federation/transport.go
index 5b5afaad5..3287f6952 100644
--- a/internal/federation/transport.go
+++ b/internal/federation/transport.go
@@ -54,17 +54,18 @@ func (f *federator) NewTransport(ctx context.Context, actorBoxIRI *url.URL, gofe
 	var username string
 	var err error
 
-	if util.IsInboxPath(actorBoxIRI) {
+	switch {
+	case util.IsInboxPath(actorBoxIRI):
 		username, err = util.ParseInboxPath(actorBoxIRI)
 		if err != nil {
 			return nil, fmt.Errorf("couldn't parse path %s as an inbox: %s", actorBoxIRI.String(), err)
 		}
-	} else if util.IsOutboxPath(actorBoxIRI) {
+	case util.IsOutboxPath(actorBoxIRI):
 		username, err = util.ParseOutboxPath(actorBoxIRI)
 		if err != nil {
 			return nil, fmt.Errorf("couldn't parse path %s as an outbox: %s", actorBoxIRI.String(), err)
 		}
-	} else {
+	default:
 		return nil, fmt.Errorf("id %s was neither an inbox path nor an outbox path", actorBoxIRI.String())
 	}