refactor: stricter domain: server-directory

toju-app/src/app/domains/server-directory/infrastructure/services/server-endpoint-health.service.ts

@@ -0,0 +1,80 @@
+import { Injectable, inject } from '@angular/core';
+import { SERVER_HEALTH_CHECK_TIMEOUT_MS } from '../constants/server-directory.infrastructure.constants';
+import type {
+  ServerEndpoint,
+  ServerEndpointHealthResult,
+  ServerHealthCheckPayload
+} from '../../domain/models/server-directory.model';
+import { ServerEndpointCompatibilityService } from './server-endpoint-compatibility.service';
+
+@Injectable({ providedIn: 'root' })
+export class ServerEndpointHealthService {
+  private readonly endpointCompatibility = inject(ServerEndpointCompatibilityService);
+
+  async probeEndpoint(
+    endpoint: Pick<ServerEndpoint, 'url'>,
+    clientVersion: string | null
+  ): Promise<ServerEndpointHealthResult> {
+    const startTime = Date.now();
+
+    try {
+      const response = await fetch(`${endpoint.url}/api/health`, {
+        method: 'GET',
+        signal: AbortSignal.timeout(SERVER_HEALTH_CHECK_TIMEOUT_MS)
+      });
+      const latency = Date.now() - startTime;
+
+      if (response.ok) {
+        const payload = await response.json() as ServerHealthCheckPayload;
+        const versionCompatibility = this.endpointCompatibility.evaluateServerVersion(
+          payload.serverVersion,
+          clientVersion
+        );
+        const serverInstanceId = typeof payload.serverInstanceId === 'string' && payload.serverInstanceId.trim().length > 0
+          ? payload.serverInstanceId.trim()
+          : undefined;
+
+        if (!versionCompatibility.isCompatible) {
+          return {
+            status: 'incompatible',
+            latency,
+            versions: {
+              serverInstanceId,
+              serverVersion: versionCompatibility.serverVersion,
+              clientVersion
+            }
+          };
+        }
+
+        return {
+          status: 'online',
+          latency,
+          versions: {
+            serverInstanceId,
+            serverVersion: versionCompatibility.serverVersion,
+            clientVersion
+          }
+        };
+      }
+
+      return { status: 'offline' };
+    } catch {
+      try {
+        const response = await fetch(`${endpoint.url}/api/servers`, {
+          method: 'GET',
+          signal: AbortSignal.timeout(SERVER_HEALTH_CHECK_TIMEOUT_MS)
+        });
+        const latency = Date.now() - startTime;
+
+        if (response.ok) {
+          return {
+            status: 'online',
+            latency
+          };
+        }
+      } catch { /* both checks failed */ }
+
+      return { status: 'offline' };
+    }
+  }
+}