fleetd #422 follow-up: make the model gate's own state observable

PeerLauncher.disabledModels() reported an empty set both when no models: block exists and when a block exists with nothing off, so fleet_profiles/GET /profiles and the startup log could not tell an inert gate from an armed one reporting zero. Add PeerLauncher.ModelGateState (configured + off), a modelGateState() default method disabledModels() now delegates to, and a CompositePeerLauncher override that reads models0() once and distinguishes the null-supplier case (no models: block) from a real, config-supplied block via identity against the NO_MODELS_CONFIGURED sentinel — reusing the exact accessor the spawn gate itself reads, per the fleetd #404 lesson. Wires the state into a new startup log line (Fleetd.modelGateCoverageLine) and a new modelGateArmed field in FleetMcp.profilesView, reported unconditionally alongside the existing modelsOff set.
2026-09-10 13:18:52 +07:00
parent 766772763f
commit 7fd914df1a
7 changed files with 388 additions and 10 deletions
@@ -69,6 +69,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.TreeSet;
 import java.util.concurrent.Executors;
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.TimeUnit;
@@ -231,6 +232,13 @@ public final class Fleetd {
                profileName -> liveCountRef.get().apply(profileName),
                quarantine,
                outagePolicy);
+        // fleetd #422 follow-up: say which of the three model-gate states the daemon booted into —
+        // no models: block at all, a block armed with nothing off, or a block with N off — the same
+        // way exhaustedPatternCoverageLine/errorPatternCoverageLine report CB-578 stage A/fleetd
+        // #201 Unit 5 coverage just below. Read from workers.modelGateState() (never a separate
+        // config.get().models() here) so this line and fleet_profiles' modelGateArmed can never
+        // disagree about what CompositePeerLauncher's spawn gate actually enforces.
+        log.info("model gate (fleetd #422): {}", modelGateCoverageLine(workers.modelGateState()));
        // CB-504: under supervision (launchd/systemd) fleetd can start before herdr's socket
        // exists. The client itself is lazy — it connects per call — but the orphan reap below is
        // the first thing that actually talks to herdr, so without this wait a boot-order race
@@ -844,6 +852,31 @@ public final class Fleetd {
                allProfiles, configuredProfiles);
    }

+    /**
+     * fleetd #422 follow-up: package-private factory for the startup line reporting which of the
+     * three central {@code models.allow:} gate states the daemon booted into. Extracted the same
+     * way {@link #exhaustedPatternCoverageLine}/{@link #errorPatternCoverageLine} are, so a
+     * dedicated test can call it directly rather than parsing log output, and so {@code main}'s
+     * only source for this line is {@link PeerLauncher#modelGateState()} — never a second,
+     * independently-derived read of {@code cfg.models()} that could disagree with what {@code
+     * CompositePeerLauncher}'s spawn gate actually enforces (the fleetd #404 lesson).
+     *
+     * <p>Unlike the two pattern-key lines above, there is no {@code UnsetMeaning} choice to make
+     * here: {@link PeerLauncher.ModelGateState#configured()} already states, unambiguously, whether
+     * an empty {@link PeerLauncher.ModelGateState#off()} means "no {@code models:} block to gate
+     * with" or "a block armed and currently reporting zero off" — the exact two states a bare
+     * {@code disabledModels()} read could not tell apart before this ticket.
+     */
+    static String modelGateCoverageLine(PeerLauncher.ModelGateState state) {
+        if (!state.configured()) {
+            return "not configured (no models: block — nothing is gated, and nothing can be)";
+        }
+        Set<String> off = state.off();
+        return off.isEmpty()
+                ? "armed (models: block present; 0 models currently turned off)"
+                : "armed (" + off.size() + " model(s) turned off: " + new TreeSet<>(off) + ")";
+    }
+
    /**
     * fleetd #416: production source for {@code fleet_list}'s per-profile capacity facts.
     *
@@ -1181,12 +1181,21 @@ public final class FleetMcp {
            result.put("coolingOff", coolingOff);
        }
        // fleetd #422: read the exact same accessor CompositePeerLauncher's spawn gate reads
-        // (PeerLauncher.disabledModels(), which for the composite is models0().offIds()) — never a
+        // (PeerLauncher.modelGateState(), which for the composite is models0() read live) — never a
        // separately-derived answer, so this status can never overstate or understate what the gate
        // actually enforces (the fleetd #404 lesson).
-        Set<String> modelsOff = workers.disabledModels();
-        if (!modelsOff.isEmpty()) {
-            result.put("modelsOff", new ArrayList<>(modelsOff));
+        //
+        // fleetd #422 follow-up: "armed" and "off" come from the ONE modelGateState() call below,
+        // never two independent reads of the gate — a reload landing between two separate reads
+        // could otherwise make them disagree. modelGateArmed is reported unconditionally (never
+        // omitted like quarantined/coolingOff above) precisely so a lead can tell "no models: block
+        // at all" (false) apart from "a models: block with nothing currently off" (true, with
+        // modelsOff simply absent below) — the two states PeerLauncher.disabledModels() alone
+        // cannot distinguish, both reporting an empty set.
+        PeerLauncher.ModelGateState modelGate = workers.modelGateState();
+        result.put("modelGateArmed", modelGate.configured());
+        if (!modelGate.off().isEmpty()) {
+            result.put("modelsOff", new ArrayList<>(modelGate.off()));
        }
        return result;
    }
@@ -644,14 +644,29 @@ public final class CompositePeerLauncher implements PeerLauncher {
    }

    /**
-     * fleetd #422: read live off {@link #models0()} — the exact same accessor {@link
+     * fleetd #422 follow-up: the single live read that answers both "is the models.allow: gate
+     * armed" and "which models are off", off the exact same accessor ({@link #models0()}) {@link
     * #enforceModelEnabled} and {@link #modelOffProfiles} read — so {@code fleet_profiles}/{@code
-     * GET /profiles} can never report a different answer than the gate enforces (the fleetd #404
-     * lesson).
+     * GET /profiles} (via {@link PeerLauncher#disabledModels()}, which now delegates here) can
+     * never report a different answer than the gate enforces (the fleetd #404 lesson), and the
+     * startup log line built from this can never disagree with either.
+     *
+     * <p>{@link #models0()} itself normalizes a {@code null} {@link #models} read to the shared
+     * {@link #NO_MODELS_CONFIGURED} sentinel — deliberately the one object no config-supplied
+     * {@code Models} instance can ever be identical to, since it is private to this class — so
+     * comparing by reference here recovers exactly the fact {@code models0()}'s normalization
+     * would otherwise erase: whether the live source was {@code null} (no {@code models:} block,
+     * armed = false) or a real, config-supplied block (armed = true, even one whose {@code allow:}
+     * is itself empty or absent — {@link FleetConfig.Models}'s "absent or empty allow: is off"
+     * wording governs config-load validation, a distinct question from whether this gate is armed
+     * for reporting).
     */
    @Override
-    public Set<String> disabledModels() {
-        return models0().offIds();
+    public PeerLauncher.ModelGateState modelGateState() {
+        FleetConfig.Models m = models0();
+        return m == NO_MODELS_CONFIGURED
+                ? PeerLauncher.ModelGateState.notConfigured()
+                : PeerLauncher.ModelGateState.armed(m.offIds());
    }

    @Override
@@ -202,8 +202,56 @@ public interface PeerLauncher {
     * can drift from what the gate ({@code CompositePeerLauncher.enforceModelEnabled} and its
     * candidate filter) actually enforces. A default of {@code Set.of()} keeps every other {@link
     * PeerLauncher} implementer (the herdr adapters, and the two test-fake implementers) unchanged.
+     *
+     * <p>fleetd #422 follow-up: this alone cannot tell "no {@code models:} block at all" from "a
+     * {@code models:} block where nothing is currently off" — both report an empty set here. Delegates
+     * to {@link #modelGateState()} so the two facts always come from the one read {@link
+     * #modelGateState()}'s implementer makes; do not override this method separately from that one.
     */
    default Set<String> disabledModels() {
-        return Set.of();
+        return modelGateState().off();
+    }
+
+    /**
+     * Whether the central {@code models.allow:} gate (fleetd #422) is armed at all, together with
+     * which model ids are currently off — fleetd #422 follow-up. {@link #disabledModels()} alone
+     * cannot distinguish two states that both report an empty set: a host with no {@code models:}
+     * block (nothing is gated, and nothing can be) and a host WITH a {@code models:} block where
+     * nothing is currently turned off (the gate is armed and reporting zero). This method exists so
+     * a caller — the startup log, {@code fleet_profiles}/{@code GET /profiles} — can tell the two
+     * apart, the same reason {@code CompletionResolver.UnsetMeaning} exists: an accessor that can
+     * legitimately report "empty" must never let a caller guess why.
+     *
+     * <p>Default {@link ModelGateState#notConfigured()} — every launcher without a {@code models:}
+     * block to read from (the herdr adapters, and the two test-fake implementers), matching {@link
+     * #disabledModels()}'s own default of an empty set.
+     */
+    default ModelGateState modelGateState() {
+        return ModelGateState.notConfigured();
+    }
+
+    /**
+     * fleetd #422 follow-up: the result of {@link #modelGateState()} — see that method's javadoc
+     * for why "armed" and "off" must be reported together from one read rather than as two
+     * separately-derived facts that a reload landing between them could make disagree.
+     *
+     * @param configured {@code true} when a {@code models:} block exists at all (armed), regardless
+     *                   of whether anything in it is currently turned off; {@code false} when there
+     *                   is no block to gate against
+     * @param off        the model ids currently turned off; always empty when {@code configured} is
+     *                   {@code false}
+     */
+    record ModelGateState(boolean configured, Set<String> off) {
+        public ModelGateState {
+            off = Set.copyOf(off);
+        }
+
+        public static ModelGateState notConfigured() {
+            return new ModelGateState(false, Set.of());
+        }
+
+        public static ModelGateState armed(Set<String> off) {
+            return new ModelGateState(true, off);
+        }
    }
 }
@@ -0,0 +1,62 @@
+package dev.ltms.fleet;
+
+import dev.ltms.fleet.peer.PeerLauncher;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+
+/**
+ * fleetd #422 follow-up: {@code Fleetd.modelGateCoverageLine} is the startup-log counterpart of
+ * {@code exhaustedPatternCoverageLine}/{@code errorPatternCoverageLine} — see {@code
+ * FleetdPatternCoverageLineTest} for the identical shape this follows — except here there is no
+ * {@code UnsetMeaning} choice for a caller to get backwards: {@link
+ * PeerLauncher.ModelGateState#configured()} already states, unambiguously, whether an empty
+ * {@link PeerLauncher.ModelGateState#off()} means "no {@code models:} block to gate with at all"
+ * or "a block armed and currently reporting zero off". This class proves {@code
+ * modelGateCoverageLine} words those two states — plus the third, N off — distinctly, so a
+ * mutation that made it ignore {@code configured()} either way is caught here.
+ */
+class FleetdModelGateCoverageLineTest {
+
+    @Test
+    @DisplayName("no models: block reports not configured, distinct from armed-with-zero")
+    void noModelsBlockReportsNotConfigured() {
+        String line = Fleetd.modelGateCoverageLine(PeerLauncher.ModelGateState.notConfigured());
+        assertEquals("not configured (no models: block — nothing is gated, and nothing can be)", line);
+    }
+
+    @Test
+    @DisplayName("a models: block armed with nothing off reports armed, distinct from not configured")
+    void armedWithNothingOffReportsArmed() {
+        String line = Fleetd.modelGateCoverageLine(PeerLauncher.ModelGateState.armed(Set.of()));
+        assertEquals("armed (models: block present; 0 models currently turned off)", line);
+    }
+
+    @Test
+    @DisplayName("a models: block with N off names the off models")
+    void armedWithModelsOffNamesThem() {
+        String line = Fleetd.modelGateCoverageLine(
+                PeerLauncher.ModelGateState.armed(Set.of("deepseek-v4-flash", "claude-opus-9000")));
+        assertEquals("armed (2 model(s) turned off: [claude-opus-9000, deepseek-v4-flash])", line);
+    }
+
+    @Test
+    @DisplayName("the three states produce pairwise-distinct wording for the same empty-looking input")
+    void theThreeStatesProduceDistinctWording() {
+        String notConfigured = Fleetd.modelGateCoverageLine(PeerLauncher.ModelGateState.notConfigured());
+        String armedZero = Fleetd.modelGateCoverageLine(PeerLauncher.ModelGateState.armed(Set.of()));
+        String armedOne = Fleetd.modelGateCoverageLine(PeerLauncher.ModelGateState.armed(Set.of("x")));
+
+        // Pinned individually above; restated here so this test alone still catches a regression
+        // even if one of the three tests above were ever deleted — the exact FleetdPatternCoverageLineTest
+        // pattern, adapted from "two keys" to "three states of one gate".
+        assertNotEquals(notConfigured, armedZero,
+                "collapsing 'no models: block' into 'armed, zero off' is fleetd #422 follow-up's exact defect");
+        assertNotEquals(armedZero, armedOne);
+        assertNotEquals(notConfigured, armedOne);
+    }
+}
@@ -0,0 +1,109 @@
+package dev.ltms.fleet.mcp;
+
+import dev.ltms.fleet.config.FleetConfig;
+import dev.ltms.fleet.guard.SubscriptionGuard;
+import dev.ltms.fleet.herdr.AgentControl;
+import dev.ltms.fleet.herdr.FakeHerdr;
+import dev.ltms.fleet.herdr.WorkspaceControl;
+import dev.ltms.fleet.member.ClaudeCodeLauncher;
+import dev.ltms.fleet.member.CompositePeerLauncher;
+import dev.ltms.fleet.member.HerdrPeerLauncher;
+import dev.ltms.fleet.peer.PeerLauncher;
+import dev.ltms.fleet.placement.BackendOutagePolicy;
+import dev.ltms.fleet.placement.BackendQuarantine;
+import dev.ltms.fleet.placement.PlacementPolicies;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
+/**
+ * fleetd #422 follow-up: {@code fleet_profiles}/{@code GET /profiles} — the reporting surface a
+ * lead actually reads — must let it tell apart the three states {@link
+ * dev.ltms.fleet.peer.PeerLauncher#disabledModels()} alone collapses into one empty set: no
+ * {@code models:} block at all, a block armed with nothing currently off, and a block with N
+ * models off. See {@link dev.ltms.fleet.peer.PeerLauncher.ModelGateState}'s javadoc for why a
+ * bare {@code disabledModels()} read cannot make this distinction, and {@link
+ * FleetMcp#profilesView} for where {@code modelGateArmed} is added alongside the existing {@code
+ * modelsOff} key.
+ *
+ * <p>Every assertion here goes through {@link FleetMcp#profilesView}, never {@code
+ * PeerLauncher.modelGateState()} directly — {@code CompositePeerLauncherTest} already proves the
+ * accessor itself; this class proves the surface a lead reads (fleet_profiles / GET /profiles)
+ * renders what that accessor reports.
+ */
+class FleetProfilesModelGateStateTest {
+
+    private static FleetConfig.Profile profile(String name, String model) {
+        return new FleetConfig.Profile(name, "http://gx00.gw:8000", model, null, "FLEETD_WORKER_TOKEN",
+                null, "tab", "fleetd-workers", "worker: {profile} #{n}", null, null, null);
+    }
+
+    private static FleetMcp.QuarantineSource noQuarantine() {
+        return new FleetMcp.QuarantineSource(_ -> null, BackendQuarantine.none(), _ -> false);
+    }
+
+    private static HerdrPeerLauncher claudeAdapter(FakeHerdr h, Map<String, FleetConfig.Profile> profiles) {
+        return new ClaudeCodeLauncher(new AgentControl(h), new WorkspaceControl(h),
+                new SubscriptionGuard(Set.of("gx00.gw")), profiles, "local", _ -> "tok");
+    }
+
+    /**
+     * State 1: no {@code models:} block at all — a plain {@code ClaudeCodeLauncher} (no {@code
+     * models:} supplier exists for it to read) has nothing to gate against, matching the fleet01
+     * host measured for this ticket: {@code grep -c '^models:' fleetd.yaml} returns 0 there.
+     */
+    @Test
+    void noModelsBlockReportsGateNotArmed() {
+        FakeHerdr h = new FakeHerdr();
+        Map<String, FleetConfig.Profile> profiles = Map.of("local", profile("local", "deepseek-v4-flash"));
+        PeerLauncher workers = claudeAdapter(h, profiles);
+
+        Map<String, Object> view = FleetMcp.profilesView(workers, noQuarantine(), FleetMcp.OutageSource.none());
+
+        assertEquals(Boolean.FALSE, view.get("modelGateArmed"),
+                "no models: block to read from — nothing is gated, and nothing can be");
+        assertFalse(view.containsKey("modelsOff"), "nothing configured, so no off set to report either");
+    }
+
+    /** State 2: a {@code models:} block is present, but nothing in it is currently turned off. */
+    @Test
+    void modelsBlockWithNothingOffReportsGateArmedAndZeroOff() {
+        FakeHerdr h = new FakeHerdr();
+        Map<String, FleetConfig.Profile> profiles = Map.of("local", profile("local", "deepseek-v4-flash"));
+        FleetConfig.Models models = new FleetConfig.Models(
+                List.of(new FleetConfig.Models.ModelEntry("deepseek-v4-flash", true)));
+        PeerLauncher workers = new CompositePeerLauncher(List.of(claudeAdapter(h, profiles)), "local", profiles,
+                PlacementPolicies.fixed(), _ -> 0, null, BackendQuarantine.none(),
+                new BackendOutagePolicy(System::nanoTime), () -> models);
+
+        Map<String, Object> view = FleetMcp.profilesView(workers, noQuarantine(), FleetMcp.OutageSource.none());
+
+        assertEquals(Boolean.TRUE, view.get("modelGateArmed"),
+                "a models: block is present, so the gate is armed even though nothing is off yet");
+        assertFalse(view.containsKey("modelsOff"),
+                "nothing is off, so the key stays absent — an empty list here would be indistinguishable "
+                        + "from today's modelsOff omission, exactly the ambiguity modelGateArmed exists to remove");
+    }
+
+    /** State 3: a {@code models:} block is present with one model currently turned off. */
+    @Test
+    void modelsBlockWithModelsOffReportsGateArmedAndTheOffSet() {
+        FakeHerdr h = new FakeHerdr();
+        Map<String, FleetConfig.Profile> profiles = Map.of("local", profile("local", "deepseek-v4-flash"));
+        FleetConfig.Models models = new FleetConfig.Models(
+                List.of(new FleetConfig.Models.ModelEntry("deepseek-v4-flash", false)));
+        PeerLauncher workers = new CompositePeerLauncher(List.of(claudeAdapter(h, profiles)), "local", profiles,
+                PlacementPolicies.fixed(), _ -> 0, null, BackendQuarantine.none(),
+                new BackendOutagePolicy(System::nanoTime), () -> models);
+
+        Map<String, Object> view = FleetMcp.profilesView(workers, noQuarantine(), FleetMcp.OutageSource.none());
+
+        assertEquals(Boolean.TRUE, view.get("modelGateArmed"));
+        assertEquals(List.of("deepseek-v4-flash"), view.get("modelsOff"));
+    }
+}
@@ -1453,6 +1453,108 @@ class CompositePeerLauncherTest {
        assertEquals(2, adapter.spawnCount("local"));
    }

+    /**
+     * fleetd #422 follow-up, acceptance criterion 2: {@link CompositePeerLauncher#modelGateState()}
+     * is LIVE — no restart — proven through a REAL {@link ConfigRef#reload()}, exactly like {@link
+     * #modelOnOffIsHotReloadedThroughARealConfigRef} above proves for the on/off gate itself. This
+     * single reload sequence walks through all three states the ticket asks for: no {@code models:}
+     * block, a block armed with nothing off, and a block with one model off — so a reload that flips
+     * between any of the three is proven live, not just the on/off edit within an already-armed block.
+     */
+    @Test
+    void modelGateStateIsHotReloadedThroughARealConfigRef(@TempDir Path dir) throws Exception {
+        Path yaml = dir.resolve("fleetd.yaml");
+        Files.writeString(yaml, """
+                bind:
+                  port: 8080
+                profiles:
+                  local:
+                    baseUrl: http://local.gw:8000
+                    model: deepseek-v4-flash
+                """);
+        FleetConfig initial = FleetConfig.load(yaml);
+        ConfigRef configRef = new ConfigRef(yaml, initial);
+
+        FakeHerdr herdr = new FakeHerdr();
+        StubLauncher adapter = new StubLauncher("claude", herdr,
+                Map.of("local", stubWorker("local")), "local", Set.of());
+        CompositePeerLauncher composite = new CompositePeerLauncher(
+                List.of(adapter), "local", configRef, _ -> 0, BackendQuarantine.none(), NO_OUTAGE);
+
+        PeerLauncher.ModelGateState notConfigured = composite.modelGateState();
+        assertFalse(notConfigured.configured(), "no models: block in the config at all");
+        assertEquals(Set.of(), notConfigured.off());
+
+        Files.writeString(yaml, """
+                bind:
+                  port: 8080
+                profiles:
+                  local:
+                    baseUrl: http://local.gw:8000
+                    model: deepseek-v4-flash
+                models:
+                  allow:
+                    - model: deepseek-v4-flash
+                      enabled: false
+                """);
+        assertTrue(configRef.reload().applied(), "adding a models: block must apply live, no restart");
+        PeerLauncher.ModelGateState armedWithOneOff = composite.modelGateState();
+        assertTrue(armedWithOneOff.configured(), "a models: block now exists — the gate is armed");
+        assertEquals(Set.of("deepseek-v4-flash"), armedWithOneOff.off());
+
+        Files.writeString(yaml, """
+                bind:
+                  port: 8080
+                profiles:
+                  local:
+                    baseUrl: http://local.gw:8000
+                    model: deepseek-v4-flash
+                models:
+                  allow:
+                    - model: deepseek-v4-flash
+                      enabled: true
+                """);
+        assertTrue(configRef.reload().applied(), "flipping the entry back on must apply live too");
+        PeerLauncher.ModelGateState armedWithZeroOff = composite.modelGateState();
+        assertTrue(armedWithZeroOff.configured(),
+                "the block is still present — armed and reporting zero, not the same as no block at all");
+        assertEquals(Set.of(), armedWithZeroOff.off());
+    }
+
+    /**
+     * fleetd #422 follow-up, acceptance criterion 3: the invariant is that an absent {@code
+     * models:} block stays permitted and must never be fatal. Proved, not assumed — a config
+     * without one loads, validates, reports the gate as not configured, AND still spawns normally
+     * (no {@link PlacementException} from a gate that has nothing to check against), using the same
+     * production-shaped {@code Supplier<FleetConfig>} wiring {@code Fleetd.main} actually uses.
+     */
+    @Test
+    void noModelsBlockConfigStillLoadsAndSpawnsNormally(@TempDir Path dir) throws Exception {
+        Path yaml = dir.resolve("fleetd.yaml");
+        Files.writeString(yaml, """
+                bind:
+                  port: 8080
+                profiles:
+                  local:
+                    baseUrl: http://local.gw:8000
+                    model: deepseek-v4-flash
+                """);
+        FleetConfig cfg = FleetConfig.load(yaml);
+        assertDoesNotThrow(cfg::validateAll, "a config with no models: block must load and validate cleanly");
+        ConfigRef configRef = new ConfigRef(yaml, cfg);
+
+        FakeHerdr herdr = new FakeHerdr();
+        StubLauncher adapter = new StubLauncher("claude", herdr,
+                Map.of("local", stubWorker("local")), "local", Set.of());
+        CompositePeerLauncher composite = new CompositePeerLauncher(
+                List.of(adapter), "local", configRef, _ -> 0, BackendQuarantine.none(), NO_OUTAGE);
+
+        assertFalse(composite.modelGateState().configured());
+        assertDoesNotThrow(() -> composite.spawn(new SpawnRequest("local", null, null)),
+                "no models: block means nothing to gate against — the spawn must go through");
+        assertEquals(1, adapter.spawnCount("local"));
+    }
+
    /** {@code fleet_profiles}/{@code GET /profiles} must read the exact same live source the gate reads. */
    @Test
    void disabledModelsReportsWhatTheGateActuallyEnforces() {