perf(session): Remove connections from session list endpoint

Including the nested connection information in the session list response
had a negative impact on performance as it created a significant
multiplier on the number of rows that needed to be fetched from the
database.

It was also determined that this information was used by neither the
admin ui nor the desktop client.

Note that nested connection information can still be retrieved via a
read request for a specific session.

internal/daemon/controller/handlers/sessions/session_service_test.go

@@ -281,7 +281,7 @@ func TestList(t *testing.T) {
 			Endpoint:    "tcp://127.0.0.1:22",
 		})
 
-		c := session.TestConnection(t, conn, sess.PublicId, "127.0.0.1", 22, "127.0.0.2", 23, "127.0.0.1")
+		session.TestConnection(t, conn, sess.PublicId, "127.0.0.1", 22, "127.0.0.2", 23, "127.0.0.1")
 
 		status, states := convertStates(sess.States)
 
@@ -304,14 +304,7 @@ func TestList(t *testing.T) {
 			Certificate:       sess.Certificate,
 			Type:              tcp.Subtype.String(),
 			AuthorizedActions: testAuthorizedActions,
-			Connections: []*pb.Connection{
-				{
-					ClientTcpAddress:   c.ClientTcpAddress,
-					ClientTcpPort:      c.ClientTcpPort,
-					EndpointTcpAddress: c.EndpointTcpAddress,
-					EndpointTcpPort:    c.EndpointTcpPort,
-				},
-			},
+			Connections:       []*pb.Connection{}, // connections should not be returned for list
 		})
 
 		totalSession = append(totalSession, wantSession[i])
@@ -326,7 +319,7 @@ func TestList(t *testing.T) {
 			Endpoint:    "tcp://127.0.0.1:22",
 		})
 
-		c = session.TestConnection(t, conn, sess.PublicId, "127.0.0.1", 22, "127.0.0.2", 23, "127.0.0.1")
+		session.TestConnection(t, conn, sess.PublicId, "127.0.0.1", 22, "127.0.0.2", 23, "127.0.0.1")
 
 		status, states = convertStates(sess.States)
 
@@ -349,14 +342,7 @@ func TestList(t *testing.T) {
 			Certificate:       sess.Certificate,
 			Type:              tcp.Subtype.String(),
 			AuthorizedActions: testAuthorizedActions,
-			Connections: []*pb.Connection{
-				{
-					ClientTcpAddress:   c.ClientTcpAddress,
-					ClientTcpPort:      c.ClientTcpPort,
-					EndpointTcpAddress: c.EndpointTcpAddress,
-					EndpointTcpPort:    c.EndpointTcpPort,
-				},
-			},
+			Connections:       []*pb.Connection{}, // connections should not be returned for list
 		})
 	}
 
@@ -423,14 +409,8 @@ func TestList(t *testing.T) {
 				require.Equal(len(tc.res.GetItems()), len(got.GetItems()), "Didn't get expected number of sessions: %v", got.GetItems())
 				for i, wantSess := range tc.res.GetItems() {
 					assert.True(got.GetItems()[i].GetExpirationTime().AsTime().Sub(wantSess.GetExpirationTime().AsTime()) < 10*time.Millisecond)
-					assert.Equal(1, len(wantSess.GetConnections()))
+					assert.Equal(0, len(wantSess.GetConnections())) // no connections on list
 					wantSess.ExpirationTime = got.GetItems()[i].GetExpirationTime()
-					for _, c := range got.GetItems()[i].GetConnections() {
-						assert.Equal("127.0.0.1", c.ClientTcpAddress)
-						assert.Equal(uint32(22), c.ClientTcpPort)
-						assert.Equal("127.0.0.2", c.EndpointTcpAddress)
-						assert.Equal(uint32(23), c.EndpointTcpPort)
-					}
 				}
 			}
 			assert.Empty(cmp.Diff(got, tc.res, protocmp.Transform()), "ListSessions(%q) got response %q, wanted %q", tc.req, got, tc.res)