protocol: move metadata to response body. Fixes #193

jeffkaufman · Jan 25, 2021 · 382e09c · 382e09c
1 parent 77863db
commit 382e09c
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Showing 3 changed files with 21 additions and 10 deletions.
diff --git a/html/demo.js b/html/demo.js
@@ -108,8 +108,7 @@ function updateCurrentUsers() {
   xhr.open('POST', server_api_path() + "?action=status", true);
   xhr.onreadystatechange = function () {
     if (this.readyState === XMLHttpRequest.DONE && this.status === 200) {
-      const x_audio_metadata = JSON.parse(this.getResponseHeader(
-        "X-Audio-Metadata"));
+      const x_audio_metadata = JSON.parse(this.response);
 
       if (x_audio_metadata.n_connected_users >= x_audio_metadata.max_users) {
         switch_app_state(APP_ROOM_FULL);
@@ -348,7 +347,7 @@ window.lyricsEntryCancel.addEventListener("click", () => {
 });
 
 window.lyricsEntryOk.addEventListener("click", () => {
-  if (window.lyricsEntryBox.value.length > 2500) {
+  if (window.lyricsEntryBox.value.length > 8500) {
     window.lyricsTooLong.style.display = "block";
   } else {
     window.lyricsEntry.style.display = "none";

diff --git a/html/net.js b/html/net.js
@@ -457,16 +457,22 @@ function handle_xhr_result(xhr, resolve, reject) {
   --xhrs_inflight;
 
   if (xhr.status == 200) {
-    var metadata = JSON.parse(xhr.getResponseHeader("X-Audio-Metadata"));
+    let metadata = JSON.parse(xhr.getResponseHeader("X-Audio-Metadata"));
+    let data = xhr.response;
+
+    const metadata_len = metadata.metadata_len;
+    if (metadata_len) {
+      metadata = JSON.parse(new TextDecoder('utf8').decode(
+        data.slice(0, metadata_len)));
+      data = data.slice(metadata_len);
+    }
+
     if (LOG_ULTRA_VERBOSE) {
       console.debug("SPAM", "metadata:", metadata);
       console.debug("SPAM", "Got XHR response w/ ID:", xhr.debug_id, "result:", xhr.response, " -- still in flight:", xhrs_inflight);
     }
 
-    return resolve({
-      metadata: metadata,
-      data: xhr.response
-    });
+    return resolve({metadata, data});
   } else {
     console.error("XHR failed w/ ID:", xhr.debug_id, "stopping:", xhr, " -- still in flight:", xhrs_inflight);
     var metadata_raw = xhr.getResponseHeader("X-Audio-Metadata");

diff --git a/server_wrapper.py b/server_wrapper.py
@@ -317,14 +317,20 @@ def do_POST(environ, start_response) -> None:
         print("Request raised exception!\nParams:", query_string, "\n", traceback.format_exc(), file=sys.stderr)
         return die500(start_response, e)
 
+    combined_data = x_audio_metadata.encode('utf-8') + data
+
+    simple_x_audio_metadata = json.dumps({
+        "metadata_len": len(x_audio_metadata)
+    })
+
     start_response(
         '200 OK',
         [("Access-Control-Allow-Origin", "*"),
          ("Access-Control-Max-Age", "86400"),
          ("Access-Control-Expose-Headers", "X-Audio-Metadata"),
-         ("X-Audio-Metadata", x_audio_metadata),
+         ("X-Audio-Metadata", simple_x_audio_metadata),
          ("Content-Type", "application/octet-stream")])
-    return data,
+    return combined_data,
 
 def application(environ, start_response):
     global backend