Overhaul sharding broadcast/send

src/sharding/Shard.js

@@ -28,6 +28,20 @@ class Shard {
      */
     this.process = childProcess.fork(path.resolve(this.manager.file), [id, this.manager.shards.size]);
   }
+
+  /**
+   * Sends a message to the shard's process.
+   * @param {*} message Message to send to the shard
+   * @returns {Promise<Shard>}
+   */
+  send(message) {
+    return new Promise((resolve, reject) => {
+      const sent = this.process.send(message, err => {
+        if (err) reject(err); else resolve(this);
+      });
+      if (!sent) throw new Error('Failed to send message to shard\'s process.');
+    });
+  }
 }
 
 module.exports = Shard;

src/sharding/ShardingManager.js

@@ -75,21 +75,14 @@ class ShardingManager extends EventEmitter {
   }
 
   /**
-   * Sends a message to a shard by ID.
-   * @param {number} id ID of the shard to send the message to
-   * @param {*} message Message to send to the shard
-   */
-  send(id, message) {
-    if (!this.shards.has(id)) throw new Error('Shard ID is invalid!');
-    this.shards.get(id).process.send(message);
-  }
-
-  /**
-   * Broadcast a message to all shards.
+   * Send a message to all shards.
    * @param {*} message Message to be sent to the shards
+   * @returns {Promise<Shard[]>}
    */
   broadcast(message) {
-    for (const shard of this.shards.values()) shard.process.send(message);
+    const promises = [];
+    for (const shard of this.shards.values()) promises.push(shard.send(message));
+    return Promise.all(promises);
   }
 }