refactor: remove unused selection factory (#3180)

This commit cleansup the broadcaster and NewSessionManager code by
removing the selection factory that has been unused since
fea5673.

server/broadcast.go

@@ -453,7 +453,7 @@ func (bsm *BroadcastSessionsManager) shouldSkipVerification(sessions []*Broadcas
 	return common.RandomUintUnder(bsm.VerificationFreq) != 0
 }
 
-func NewSessionManager(ctx context.Context, node *core.LivepeerNode, params *core.StreamParameters, sel BroadcastSessionsSelectorFactory) *BroadcastSessionsManager {
+func NewSessionManager(ctx context.Context, node *core.LivepeerNode, params *core.StreamParameters) *BroadcastSessionsManager {
 	if node.Capabilities != nil {
 		params.Capabilities.SetMinVersionConstraint(node.Capabilities.MinVersionConstraint())
 	}

server/broadcast_test.go

@@ -65,10 +65,6 @@ func StubBroadcastSession(transcoder string) *BroadcastSession {
 	}
 }
 
-func selFactoryEmpty() BroadcastSessionsSelector {
-	return &LIFOSelector{}
-}
-
 func bsmWithSessList(sessList []*BroadcastSession) *BroadcastSessionsManager {
 	return bsmWithSessListExt(sessList, nil, false)
 }
@@ -299,7 +295,7 @@ func TestNewSessionManager(t *testing.T) {
 
 	// Check empty pool produces expected numOrchs
 
-	sess := NewSessionManager(context.TODO(), n, params, selFactoryEmpty)
+	sess := NewSessionManager(context.TODO(), n, params)
 	assert.Equal(0, sess.trustedPool.numOrchs)
 	assert.Equal(0, sess.untrustedPool.numOrchs)
 
@@ -308,7 +304,7 @@ func TestNewSessionManager(t *testing.T) {
 	n.OrchestratorPool = sd
 	max := int(common.HTTPTimeout.Seconds()/SegLen.Seconds()) * 2
 	for i := 0; i < 10; i++ {
-		sess = NewSessionManager(context.TODO(), n, params, selFactoryEmpty)
+		sess = NewSessionManager(context.TODO(), n, params)
 		if i < max {
 			assert.Equal(i, sess.trustedPool.numOrchs)
 		} else {

server/mediaserver.go

@@ -524,17 +524,8 @@ func (s *LivepeerServer) registerConnection(ctx context.Context, rtmpStrm stream
 	// do not obtain this lock again while initializing channel is open, it will cause deadlock if other goroutine already obtained the lock and called getActiveRtmpConnectionUnsafe()
 	s.connectionLock.Unlock()
 
-	// initialize session manager
-	var stakeRdr stakeReader
-	if s.LivepeerNode.Eth != nil {
-		stakeRdr = &storeStakeReader{store: s.LivepeerNode.Database}
-	}
-	selFactory := func() BroadcastSessionsSelector {
-		return NewMinLSSelector(stakeRdr, SELECTOR_LATENCY_SCORE_THRESHOLD, s.LivepeerNode.SelectionAlgorithm, s.LivepeerNode.OrchPerfScore)
-	}
-
 	// safe, because other goroutines should be waiting on initializing channel
-	cxn.sessManager = NewSessionManager(ctx, s.LivepeerNode, params, selFactory)
+	cxn.sessManager = NewSessionManager(ctx, s.LivepeerNode, params)
 
 	// populate fields and signal initializing channel
 	s.serverLock.Lock()