1 files changed, 40 insertions, 38 deletions
diff --git a/std/ws/example_server.ts b/std/ws/example_server.ts
index 947b807ca..3a9815957 100644
--- a/std/ws/example_server.ts
+++ b/std/ws/example_server.ts
@@ -6,50 +6,52 @@ import {
   isWebSocketPingEvent,
 } from "./mod.ts";
 
-/** websocket echo server */
-const port = Deno.args[0] || "8080";
-console.log(`websocket server is running on :${port}`);
-for await (const req of serve(`:${port}`)) {
-  const { conn, r: bufReader, w: bufWriter, headers } = req;
+if (import.meta.main) {
+  /** websocket echo server */
+  const port = Deno.args[0] || "8080";
+  console.log(`websocket server is running on :${port}`);
+  for await (const req of serve(`:${port}`)) {
+    const { conn, r: bufReader, w: bufWriter, headers } = req;
 
-  try {
-    const sock = await acceptWebSocket({
-      conn,
-      bufReader,
-      bufWriter,
-      headers,
-    });
+    try {
+      const sock = await acceptWebSocket({
+        conn,
+        bufReader,
+        bufWriter,
+        headers,
+      });
 
-    console.log("socket connected!");
+      console.log("socket connected!");
 
-    try {
-      for await (const ev of sock) {
-        if (typeof ev === "string") {
-          // text message
-          console.log("ws:Text", ev);
-          await sock.send(ev);
-        } else if (ev instanceof Uint8Array) {
-          // binary message
-          console.log("ws:Binary", ev);
-        } else if (isWebSocketPingEvent(ev)) {
-          const [, body] = ev;
-          // ping
-          console.log("ws:Ping", body);
-        } else if (isWebSocketCloseEvent(ev)) {
-          // close
-          const { code, reason } = ev;
-          console.log("ws:Close", code, reason);
+      try {
+        for await (const ev of sock) {
+          if (typeof ev === "string") {
+            // text message
+            console.log("ws:Text", ev);
+            await sock.send(ev);
+          } else if (ev instanceof Uint8Array) {
+            // binary message
+            console.log("ws:Binary", ev);
+          } else if (isWebSocketPingEvent(ev)) {
+            const [, body] = ev;
+            // ping
+            console.log("ws:Ping", body);
+          } else if (isWebSocketCloseEvent(ev)) {
+            // close
+            const { code, reason } = ev;
+            console.log("ws:Close", code, reason);
+          }
         }
-      }
-    } catch (err) {
-      console.error(`failed to receive frame: ${err}`);
+      } catch (err) {
+        console.error(`failed to receive frame: ${err}`);
 
-      if (!sock.isClosed) {
-        await sock.close(1000).catch(console.error);
+        if (!sock.isClosed) {
+          await sock.close(1000).catch(console.error);
+        }
       }
+    } catch (err) {
+      console.error(`failed to accept websocket: ${err}`);
+      await req.respond({ status: 400 });
     }
-  } catch (err) {
-    console.error(`failed to accept websocket: ${err}`);
-    await req.respond({ status: 400 });
   }
 }