🎉 初始化项目

web-app/public/scripts/util/SimpleMutex.js

@@ -0,0 +1,44 @@
+/**
+ * A simple mutex class to prevent concurrent updates.
+ */
+export class SimpleMutex {
+    /**
+     * @type {boolean}
+     */
+    isBusy = false;
+
+    /**
+     * @type {Function}
+     */
+    callback = () => {};
+
+    /**
+     * Constructs a SimpleMutex.
+     * @param {Function} callback Callback function.
+     */
+    constructor(callback) {
+        this.isBusy = false;
+        this.callback = callback;
+    }
+
+    /**
+     * Updates the mutex by calling the callback if not busy.
+     * @param  {...any} args Callback args
+     * @returns {Promise<void>}
+     */
+    async update(...args) {
+        // Don't touch me I'm busy...
+        if (this.isBusy) {
+            return;
+        }
+
+        // I'm free. Let's update!
+        try {
+            this.isBusy = true;
+            await this.callback(...args);
+        }
+        finally {
+            this.isBusy = false;
+        }
+    }
+}