Examples with RoundRobinPicker io.grpc.grpclb.GrpclbLoadBalancer.RoundRobinPicker used on opensource projects

Example 1 with RoundRobinPicker

use of io.grpc.grpclb.GrpclbLoadBalancer.RoundRobinPicker in project grpc-java by grpc.

the class GrpclbLoadBalancerTest method roundRobinPicker.

@Test
public void roundRobinPicker() {
    Subchannel subchannel = mock(Subchannel.class);
    RoundRobinEntry r1 = new RoundRobinEntry(Status.UNAVAILABLE.withDescription("Just error"));
    RoundRobinEntry r2 = new RoundRobinEntry(subchannel, "LBTOKEN0001");
    RoundRobinEntry r3 = new RoundRobinEntry(subchannel, "LBTOKEN0002");
    List<RoundRobinEntry> list = Arrays.asList(r1, r2, r3);
    RoundRobinPicker picker = new RoundRobinPicker(list);
    PickSubchannelArgs args1 = mock(PickSubchannelArgs.class);
    Metadata headers1 = new Metadata();
    when(args1.getHeaders()).thenReturn(headers1);
    assertSame(r1.result, picker.pickSubchannel(args1));
    verify(args1).getHeaders();
    assertFalse(headers1.containsKey(GrpclbLoadBalancer.TOKEN_KEY));
    PickSubchannelArgs args2 = mock(PickSubchannelArgs.class);
    Metadata headers2 = new Metadata();
    // The existing token on the headers will be replaced
    headers2.put(GrpclbLoadBalancer.TOKEN_KEY, "LBTOKEN__OLD");
    when(args2.getHeaders()).thenReturn(headers2);
    assertSame(r2.result, picker.pickSubchannel(args2));
    verify(args2).getHeaders();
    assertThat(headers2.getAll(GrpclbLoadBalancer.TOKEN_KEY)).containsExactly("LBTOKEN0001");
    PickSubchannelArgs args3 = mock(PickSubchannelArgs.class);
    Metadata headers3 = new Metadata();
    when(args3.getHeaders()).thenReturn(headers3);
    assertSame(r3.result, picker.pickSubchannel(args3));
    verify(args3).getHeaders();
    assertThat(headers3.getAll(GrpclbLoadBalancer.TOKEN_KEY)).containsExactly("LBTOKEN0002");
    PickSubchannelArgs args4 = mock(PickSubchannelArgs.class);
    Metadata headers4 = new Metadata();
    when(args4.getHeaders()).thenReturn(headers4);
    assertSame(r1.result, picker.pickSubchannel(args4));
    verify(args4).getHeaders();
    assertFalse(headers4.containsKey(GrpclbLoadBalancer.TOKEN_KEY));
    verify(subchannel, never()).getAttributes();
}

Example 2 with RoundRobinPicker

use of io.grpc.grpclb.GrpclbLoadBalancer.RoundRobinPicker in project grpc-java by grpc.

the class GrpclbLoadBalancerTest method grpclbWorking.

@Test
public void grpclbWorking() {
    InOrder inOrder = inOrder(helper);
    List<ResolvedServerInfoGroup> grpclbResolutionList = createResolvedServerInfoGroupList(true, true);
    Attributes grpclbResolutionAttrs = Attributes.newBuilder().set(GrpclbConstants.ATTR_LB_POLICY, LbPolicy.GRPCLB).build();
    deliverResolvedAddresses(grpclbResolutionList, grpclbResolutionAttrs);
    assertSame(LbPolicy.GRPCLB, balancer.getLbPolicy());
    assertNull(balancer.getDelegate());
    verify(helper).createOobChannel(eq(grpclbResolutionList.get(0).toEquivalentAddressGroup()), eq(lbAuthority(0)));
    assertEquals(1, fakeOobChannels.size());
    ManagedChannel oobChannel = fakeOobChannels.poll();
    verify(mockLbService).balanceLoad(lbResponseObserverCaptor.capture());
    StreamObserver<LoadBalanceResponse> lbResponseObserver = lbResponseObserverCaptor.getValue();
    // Simulate receiving LB response
    List<ServerEntry> backends1 = Arrays.asList(new ServerEntry("127.0.0.1", 2000, "token0001"), new ServerEntry("127.0.0.1", 2010, "token0002"));
    inOrder.verify(helper, never()).updatePicker(any(SubchannelPicker.class));
    lbResponseObserver.onNext(buildInitialResponse());
    lbResponseObserver.onNext(buildLbResponse(backends1));
    inOrder.verify(helper).createSubchannel(eq(new EquivalentAddressGroup(backends1.get(0).addr)), any(Attributes.class));
    inOrder.verify(helper).createSubchannel(eq(new EquivalentAddressGroup(backends1.get(1).addr)), any(Attributes.class));
    assertEquals(2, mockSubchannels.size());
    Subchannel subchannel1 = mockSubchannels.poll();
    Subchannel subchannel2 = mockSubchannels.poll();
    verify(subchannel1).requestConnection();
    verify(subchannel2).requestConnection();
    assertEquals(new EquivalentAddressGroup(backends1.get(0).addr), subchannel1.getAddresses());
    assertEquals(new EquivalentAddressGroup(backends1.get(1).addr), subchannel2.getAddresses());
    // Before any subchannel is READY, a buffer picker will be provided
    inOrder.verify(helper).updatePicker(same(GrpclbLoadBalancer.BUFFER_PICKER));
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forNonError(CONNECTING));
    deliverSubchannelState(subchannel2, ConnectivityStateInfo.forNonError(CONNECTING));
    inOrder.verify(helper, times(2)).updatePicker(same(GrpclbLoadBalancer.BUFFER_PICKER));
    // Let subchannels be connected
    deliverSubchannelState(subchannel2, ConnectivityStateInfo.forNonError(READY));
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker1 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker1.list).containsExactly(new RoundRobinEntry(subchannel2, "token0002"));
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forNonError(READY));
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker2 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker2.list).containsExactly(new RoundRobinEntry(subchannel1, "token0001"), new RoundRobinEntry(subchannel2, "token0002")).inOrder();
    // Disconnected subchannels
    verify(subchannel1).requestConnection();
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forNonError(IDLE));
    verify(subchannel1, times(2)).requestConnection();
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker3 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker3.list).containsExactly(new RoundRobinEntry(subchannel2, "token0002"));
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forNonError(CONNECTING));
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker4 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker4.list).containsExactly(new RoundRobinEntry(subchannel2, "token0002"));
    // As long as there is at least one READY subchannel, round robin will work.
    Status error1 = Status.UNAVAILABLE.withDescription("error1");
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forTransientFailure(error1));
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker5 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker5.list).containsExactly(new RoundRobinEntry(subchannel2, "token0002"));
    // If no subchannel is READY, will propagate an error from an arbitrary subchannel (but here
    // only subchannel1 has error).
    verify(subchannel2).requestConnection();
    deliverSubchannelState(subchannel2, ConnectivityStateInfo.forNonError(IDLE));
    verify(subchannel2, times(2)).requestConnection();
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    ErrorPicker picker6 = (ErrorPicker) pickerCaptor.getValue();
    assertNull(picker6.result.getSubchannel());
    assertSame(error1, picker6.result.getStatus());
    // Update backends, with a drop entry
    List<ServerEntry> backends2 = Arrays.asList(// New address
    new ServerEntry("127.0.0.1", 2030, "token0003"), // drop
    null, // Existing address with token changed
    new ServerEntry("127.0.0.1", 2010, "token0004"), // New address appearing second time
    new ServerEntry("127.0.0.1", 2030, "token0005"));
    verify(subchannel1, never()).shutdown();
    lbResponseObserver.onNext(buildLbResponse(backends2));
    // not in backends2, closed
    verify(subchannel1).shutdown();
    // backends2[2], will be kept
    verify(subchannel2, never()).shutdown();
    inOrder.verify(helper, never()).createSubchannel(eq(new EquivalentAddressGroup(backends2.get(2).addr)), any(Attributes.class));
    inOrder.verify(helper).createSubchannel(eq(new EquivalentAddressGroup(backends2.get(0).addr)), any(Attributes.class));
    assertEquals(1, mockSubchannels.size());
    Subchannel subchannel3 = mockSubchannels.poll();
    verify(subchannel3).requestConnection();
    assertEquals(new EquivalentAddressGroup(backends2.get(0).addr), subchannel3.getAddresses());
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker7 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker7.list).containsExactly(GrpclbLoadBalancer.DROP_ENTRY);
    // State updates on obsolete subchannel1 will have no effect
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forNonError(READY));
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forTransientFailure(Status.UNAVAILABLE));
    deliverSubchannelState(subchannel1, ConnectivityStateInfo.forNonError(SHUTDOWN));
    inOrder.verifyNoMoreInteractions();
    deliverSubchannelState(subchannel3, ConnectivityStateInfo.forNonError(READY));
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker8 = (RoundRobinPicker) pickerCaptor.getValue();
    // subchannel2 is still IDLE, thus not in the active list
    assertThat(picker8.list).containsExactly(new RoundRobinEntry(subchannel3, "token0003"), GrpclbLoadBalancer.DROP_ENTRY, new RoundRobinEntry(subchannel3, "token0005")).inOrder();
    // subchannel2 becomes READY and makes it into the list
    deliverSubchannelState(subchannel2, ConnectivityStateInfo.forNonError(READY));
    inOrder.verify(helper).updatePicker(pickerCaptor.capture());
    RoundRobinPicker picker9 = (RoundRobinPicker) pickerCaptor.getValue();
    assertThat(picker9.list).containsExactly(new RoundRobinEntry(subchannel3, "token0003"), GrpclbLoadBalancer.DROP_ENTRY, new RoundRobinEntry(subchannel2, "token0004"), new RoundRobinEntry(subchannel3, "token0005")).inOrder();
    verify(subchannel3, never()).shutdown();
    assertFalse(oobChannel.isShutdown());
    assertEquals(1, lbRequestObservers.size());
    verify(lbRequestObservers.peek(), never()).onCompleted();
    verify(lbRequestObservers.peek(), never()).onError(any(Throwable.class));
}