feat(web): add xtext websocket client

1 files changed, 47 insertions, 0 deletions

diff --git a/language-web/src/main/js/editor/PendingRequest.ts b/language-web/src/main/js/editor/PendingRequest.ts
new file mode 100644
index 00000000..784f06ec
--- /dev/null
+++ b/language-web/src/main/js/editor/PendingRequest.ts
@@ -0,0 +1,47 @@
+import { getLogger } from '../logging';
+
+const REQUEST_TIMEOUT_MS = 1000;
+
+const log = getLogger('PendingRequest');
+
+export class PendingRequest {
+  private readonly resolveCallback: (value: unknown) => void;
+
+  private readonly rejectCallback: (reason?: unknown) => void;
+
+  private resolved = false;
+
+  private timeoutId: NodeJS.Timeout;
+
+  constructor(resolve: (value: unknown) => void, reject: (reason?: unknown) => void) {
+    this.resolveCallback = resolve;
+    this.rejectCallback = reject;
+    this.timeoutId = setTimeout(() => {
+      if (!this.resolved) {
+        this.reject(new Error('Request timed out'));
+      }
+    }, REQUEST_TIMEOUT_MS);
+  }
+
+  resolve(value: unknown): void {
+    if (this.resolved) {
+      log.warn('Trying to resolve already resolved promise');
+      return;
+    }
+    this.markResolved();
+    this.resolveCallback(value);
+  }
+
+  reject(reason?: unknown): void {
+    if (this.resolved) {
+      log.warn('Trying to reject already resolved promise');
+    }
+    this.markResolved();
+    this.rejectCallback(reason);
+  }
+
+  private markResolved() {
+    this.resolved = true;
+    clearTimeout(this.timeoutId);
+  }
+}