feat(alerting): AGENT_STATE evaluator

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cameleer-server-app/src/main/java/com/cameleer/server/app/alerting/eval/AgentStateEvaluator.java

@@ -0,0 +1,61 @@
+package com.cameleer.server.app.alerting.eval;
+
+import com.cameleer.server.core.agent.AgentInfo;
+import com.cameleer.server.core.agent.AgentRegistryService;
+import com.cameleer.server.core.agent.AgentState;
+import com.cameleer.server.core.alerting.AgentStateCondition;
+import com.cameleer.server.core.alerting.AlertRule;
+import com.cameleer.server.core.alerting.AlertScope;
+import com.cameleer.server.core.alerting.ConditionKind;
+import org.springframework.stereotype.Component;
+
+import java.time.Instant;
+import java.util.List;
+import java.util.Map;
+
+@Component
+public class AgentStateEvaluator implements ConditionEvaluator<AgentStateCondition> {
+
+    private final AgentRegistryService registry;
+
+    public AgentStateEvaluator(AgentRegistryService registry) {
+        this.registry = registry;
+    }
+
+    @Override
+    public ConditionKind kind() { return ConditionKind.AGENT_STATE; }
+
+    @Override
+    public EvalResult evaluate(AgentStateCondition c, AlertRule rule, EvalContext ctx) {
+        AgentState target = AgentState.valueOf(c.state());
+        Instant cutoff = ctx.now().minusSeconds(c.forSeconds());
+
+        List<AgentInfo> hits = registry.findAll().stream()
+                .filter(a -> matchesScope(a, c.scope()))
+                .filter(a -> a.state() == target)
+                .filter(a -> a.lastHeartbeat() != null && a.lastHeartbeat().isBefore(cutoff))
+                .toList();
+
+        if (hits.isEmpty()) return EvalResult.Clear.INSTANCE;
+
+        AgentInfo first = hits.get(0);
+        return new EvalResult.Firing(
+                (double) hits.size(), null,
+                Map.of(
+                        "agent", Map.of(
+                                "id",    first.instanceId(),
+                                "name",  first.displayName(),
+                                "state", first.state().name()
+                        ),
+                        "app", Map.of("slug", first.applicationId())
+                )
+        );
+    }
+
+    private static boolean matchesScope(AgentInfo a, AlertScope s) {
+        if (s == null) return true;
+        if (s.appSlug() != null && !s.appSlug().equals(a.applicationId())) return false;
+        if (s.agentId() != null && !s.agentId().equals(a.instanceId())) return false;
+        return true;
+    }
+}

cameleer-server-app/src/test/java/com/cameleer/server/app/alerting/eval/AgentStateEvaluatorTest.java

@@ -0,0 +1,104 @@
+package com.cameleer.server.app.alerting.eval;
+
+import com.cameleer.server.core.agent.AgentInfo;
+import com.cameleer.server.core.agent.AgentRegistryService;
+import com.cameleer.server.core.agent.AgentState;
+import com.cameleer.server.core.alerting.*;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.time.Instant;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+class AgentStateEvaluatorTest {
+
+    private AgentRegistryService registry;
+    private AgentStateEvaluator eval;
+
+    private static final UUID ENV_ID  = UUID.fromString("bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb");
+    private static final UUID RULE_ID = UUID.fromString("aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa");
+    private static final Instant NOW  = Instant.parse("2026-04-19T10:00:00Z");
+
+    @BeforeEach
+    void setUp() {
+        registry = mock(AgentRegistryService.class);
+        eval = new AgentStateEvaluator(registry);
+    }
+
+    private AlertRule ruleWith(AlertCondition condition) {
+        return new AlertRule(RULE_ID, ENV_ID, "test", null,
+                AlertSeverity.WARNING, true, condition.kind(), condition,
+                60, 0, 0, null, null, List.of(), List.of(),
+                null, null, null, Map.of(), null, null, null, null);
+    }
+
+    @Test
+    void firesWhenAgentInTargetStateForScope() {
+        when(registry.findAll()).thenReturn(List.of(
+                new AgentInfo("a1", "Agent1", "orders", ENV_ID.toString(), "1.0",
+                        List.of(), Map.of(), AgentState.DEAD,
+                        NOW.minusSeconds(200), NOW.minusSeconds(120), null)
+        ));
+        var condition = new AgentStateCondition(new AlertScope("orders", null, null), "DEAD", 60);
+        var rule = ruleWith(condition);
+        EvalResult r = eval.evaluate(condition, rule, new EvalContext("default", NOW, new TickCache()));
+        assertThat(r).isInstanceOf(EvalResult.Firing.class);
+        var firing = (EvalResult.Firing) r;
+        assertThat(firing.currentValue()).isEqualTo(1.0);
+    }
+
+    @Test
+    void clearWhenNoMatchingAgents() {
+        when(registry.findAll()).thenReturn(List.of(
+                new AgentInfo("a1", "Agent1", "orders", ENV_ID.toString(), "1.0",
+                        List.of(), Map.of(), AgentState.LIVE,
+                        NOW.minusSeconds(200), NOW.minusSeconds(10), null)
+        ));
+        var condition = new AgentStateCondition(new AlertScope("orders", null, null), "DEAD", 60);
+        var rule = ruleWith(condition);
+        EvalResult r = eval.evaluate(condition, rule, new EvalContext("default", NOW, new TickCache()));
+        assertThat(r).isEqualTo(EvalResult.Clear.INSTANCE);
+    }
+
+    @Test
+    void clearWhenAgentInStateBelowForSecondsCutoff() {
+        // Agent is DEAD but only 30s ago — forSeconds=60 → not yet long enough
+        when(registry.findAll()).thenReturn(List.of(
+                new AgentInfo("a1", "Agent1", "orders", ENV_ID.toString(), "1.0",
+                        List.of(), Map.of(), AgentState.DEAD,
+                        NOW.minusSeconds(200), NOW.minusSeconds(30), null)
+        ));
+        var condition = new AgentStateCondition(new AlertScope("orders", null, null), "DEAD", 60);
+        var rule = ruleWith(condition);
+        EvalResult r = eval.evaluate(condition, rule, new EvalContext("default", NOW, new TickCache()));
+        assertThat(r).isEqualTo(EvalResult.Clear.INSTANCE);
+    }
+
+    @Test
+    void kindIsAgentState() {
+        assertThat(eval.kind()).isEqualTo(ConditionKind.AGENT_STATE);
+    }
+
+    @Test
+    void scopeFilterByAgentId() {
+        when(registry.findAll()).thenReturn(List.of(
+                new AgentInfo("a1", "Agent1", "orders", ENV_ID.toString(), "1.0",
+                        List.of(), Map.of(), AgentState.DEAD,
+                        NOW.minusSeconds(200), NOW.minusSeconds(120), null),
+                new AgentInfo("a2", "Agent2", "orders", ENV_ID.toString(), "1.0",
+                        List.of(), Map.of(), AgentState.DEAD,
+                        NOW.minusSeconds(200), NOW.minusSeconds(120), null)
+        ));
+        // filter to only a1
+        var condition = new AgentStateCondition(new AlertScope("orders", null, "a1"), "DEAD", 60);
+        EvalResult r = eval.evaluate(condition, ruleWith(condition), new EvalContext("default", NOW, new TickCache()));
+        assertThat(r).isInstanceOf(EvalResult.Firing.class);
+        assertThat(((EvalResult.Firing) r).currentValue()).isEqualTo(1.0);
+    }
+}