From 68af95d927064149f4fdec6a70ad955b083ece81 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Wed, 29 Apr 2020 12:27:51 -0400
Subject: [PATCH 01/14] Create server-sent-events.js

---
 core/modules/server/server-sent-events.js | 68 +++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 core/modules/server/server-sent-events.js

diff --git a/core/modules/server/server-sent-events.js b/core/modules/server/server-sent-events.js
new file mode 100644
index 00000000000..3f0308b1dfe
--- /dev/null
+++ b/core/modules/server/server-sent-events.js
@@ -0,0 +1,68 @@
+/*\
+title: $:/core/modules/server/server-sent-events.js
+type: application/javascript
+module-type: library
+\*/
+class ServerSentEvents {
+  /**
+   * @param {string} prefix 
+   * Usually the plugin path, such as `plugins/tiddlywiki/tiddlyweb`. 
+   * The route will match `/events/${prefix}` exactly.
+   * @param {(
+   *   request: import("http").IncomingMessage, 
+   *   state, 
+   *   emit: (event: string, data: string) => void, 
+   *   end: () => void
+   * ) => void} handler 
+   * A function that will be called each time a request 
+   * comes in with the request and state from the 
+   * route and an emit function to call.
+   */
+  constructor(prefix, handler) {
+    this.handler = handler;
+    this.prefix = prefix;
+  }
+  getExports() {
+    return {
+      bodyFormat: "stream",
+      method: "GET",
+      path: new RegExp("^/events/" + this.prefix + "$"),
+      handler: this.handleEventRequest.bind(this)
+    }
+  }
+  /**
+   * 
+   * @param {import("http").IncomingMessage} request 
+   * @param {import("http").ServerResponse} response 
+   * @param {*} state 
+   */
+  handleEventRequest(request, response, state) {
+    if (request.headers.accept && request.headers.accept.startsWith('text/event-stream')) {
+      response.writeHead(200, {
+        'Content-Type': 'text/event-stream',
+        'Cache-Control': 'no-cache',
+        'Connection': 'keep-alive'
+      });
+      response.write("\n", "utf8");
+      this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
+    } else {
+      response.writeHead(406, "Not Acceptable", {});
+      response.end();
+    }
+  }
+  emit(response, event, data) {
+
+    if (typeof event !== "string" || event.indexOf("\n") !== -1)
+      throw new Error("type must be a single-line string");
+
+    if (typeof data !== "string" || data.indexOf("\n") !== -1)
+      throw new Error("data must be a single-line string");
+
+    response.write("event: " + type + "\n", "utf8");
+    response.write("data: " + data + "\n\n", "utf8");
+  }
+  end(response) {
+    response.end();
+  }
+}
+exports.ServerSentEvents = ServerSentEvents;

From 3d59bd2862b9eb6a4adf478a74defb92f3aba0af Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Wed, 29 Apr 2020 12:29:45 -0400
Subject: [PATCH 02/14] Create sse-change-listener.js

---
 .../tiddlyweb/sse-change-listener.js          | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 plugins/tiddlywiki/tiddlyweb/sse-change-listener.js

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-change-listener.js b/plugins/tiddlywiki/tiddlyweb/sse-change-listener.js
new file mode 100644
index 00000000000..c56988bcee6
--- /dev/null
+++ b/plugins/tiddlywiki/tiddlyweb/sse-change-listener.js
@@ -0,0 +1,21 @@
+const { ServerSentEvents } = require("$:/core/modules/server/server-sent-events.js");
+/** @type {Record<any, {
+ *   request: import("http").IncomingMessage, 
+ *   state, 
+ *   emit: (event: string, data: string) => void, 
+ *   end: () => void
+ * }[]>} */
+const wikis = {};
+function setupWiki(wiki) {
+  wikis[state.wiki] = [];
+  state.wiki.addEventListener("change", (changes) => {
+    wikis[state.wiki].forEach(({ request, state, emit, end }) => {
+      emit("change", JSON.stringify(changes));
+    });
+  });
+}
+const events = new ServerSentEvents("test", (request, state, emit, end) => {
+  if (!wikis[state.wiki]) setupWiki(state.wiki);
+  wikis[state.wiki].push({ request, state, emit, end });
+});
+module.exports = events.getExports();

From 8da6630aee05d5f6fbfc04d58c73d84a86fb6f0c Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Wed, 29 Apr 2020 12:49:59 -0400
Subject: [PATCH 03/14] Implement server sent events

---
 core/modules/server/server-sent-events.js     |  5 ++--
 .../tiddlyweb/sse-change-listener.js          | 21 --------------
 plugins/tiddlywiki/tiddlyweb/sse-client.js    | 18 ++++++++++++
 plugins/tiddlywiki/tiddlyweb/sse-server.js    | 29 +++++++++++++++++++
 4 files changed, 49 insertions(+), 24 deletions(-)
 delete mode 100644 plugins/tiddlywiki/tiddlyweb/sse-change-listener.js
 create mode 100644 plugins/tiddlywiki/tiddlyweb/sse-client.js
 create mode 100644 plugins/tiddlywiki/tiddlyweb/sse-server.js

diff --git a/core/modules/server/server-sent-events.js b/core/modules/server/server-sent-events.js
index 3f0308b1dfe..bfe7a19a8e9 100644
--- a/core/modules/server/server-sent-events.js
+++ b/core/modules/server/server-sent-events.js
@@ -43,7 +43,7 @@ class ServerSentEvents {
         'Cache-Control': 'no-cache',
         'Connection': 'keep-alive'
       });
-      response.write("\n", "utf8");
+
       this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
     } else {
       response.writeHead(406, "Not Acceptable", {});
@@ -58,8 +58,7 @@ class ServerSentEvents {
     if (typeof data !== "string" || data.indexOf("\n") !== -1)
       throw new Error("data must be a single-line string");
 
-    response.write("event: " + type + "\n", "utf8");
-    response.write("data: " + data + "\n\n", "utf8");
+    response.write(`event: ${event}\ndata: ${data}\n\n`, "utf8");
   }
   end(response) {
     response.end();
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-change-listener.js b/plugins/tiddlywiki/tiddlyweb/sse-change-listener.js
deleted file mode 100644
index c56988bcee6..00000000000
--- a/plugins/tiddlywiki/tiddlyweb/sse-change-listener.js
+++ /dev/null
@@ -1,21 +0,0 @@
-const { ServerSentEvents } = require("$:/core/modules/server/server-sent-events.js");
-/** @type {Record<any, {
- *   request: import("http").IncomingMessage, 
- *   state, 
- *   emit: (event: string, data: string) => void, 
- *   end: () => void
- * }[]>} */
-const wikis = {};
-function setupWiki(wiki) {
-  wikis[state.wiki] = [];
-  state.wiki.addEventListener("change", (changes) => {
-    wikis[state.wiki].forEach(({ request, state, emit, end }) => {
-      emit("change", JSON.stringify(changes));
-    });
-  });
-}
-const events = new ServerSentEvents("test", (request, state, emit, end) => {
-  if (!wikis[state.wiki]) setupWiki(state.wiki);
-  wikis[state.wiki].push({ request, state, emit, end });
-});
-module.exports = events.getExports();
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
new file mode 100644
index 00000000000..7301bf43096
--- /dev/null
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -0,0 +1,18 @@
+/*\
+title: $:/plugins/tiddlywiki/tiddlyweb/sse-client.js
+type: application/javascript
+module-type: startup
+
+GET /recipes/default/tiddlers/:title
+
+\*/
+exports.name = "/events/plugins/tiddlywiki/tiddlyweb";
+exports.after = ["startup"];
+exports.synchronous = true;
+exports.platforms = ["browser"];
+exports.startup = function () {
+  var events = new EventSource("/events/plugins/tiddlywiki/tiddlyweb");
+  events.addEventListener("change", function () {
+    $tw.syncer.syncFromServer();
+  });
+}
\ No newline at end of file
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
new file mode 100644
index 00000000000..0c2a1bd72e3
--- /dev/null
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -0,0 +1,29 @@
+/*\
+title: $:/plugins/tiddlywiki/tiddlyweb/sse-server.js
+type: application/javascript
+module-type: route
+
+GET /events/plugins/tiddlywiki/tiddlyweb
+
+\*/
+var ServerSentEvents = require("$:/core/modules/server/server-sent-events.js").ServerSentEvents;
+/** @type {Record<any, {
+ *   request: import("http").IncomingMessage, 
+ *   state, 
+ *   emit: (event: string, data: string) => void, 
+ *   end: () => void
+ * }[]>} */
+var wikis = {};
+function setupWiki(wiki) {
+  wikis[wiki] = [];
+  wiki.addEventListener("change", function (changes) {
+    wikis[wiki].forEach(function (item) {
+      item.emit("change", JSON.stringify(changes));
+    });
+  });
+}
+var events = new ServerSentEvents("plugins/tiddlywiki/tiddlyweb", (request, state, emit, end) => {
+  if (!wikis[state.wiki]) setupWiki(state.wiki);
+  wikis[state.wiki].push({ request: request, state: state, emit: emit, end: end });
+});
+module.exports = events.getExports();

From c013a90db8718a8e640e00387a79107f6736963e Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Wed, 29 Apr 2020 13:02:09 -0400
Subject: [PATCH 04/14] Convert to ES5 and wrap in function

---
 core/modules/server/server-sent-events.js  | 80 ++++++++++++----------
 plugins/tiddlywiki/tiddlyweb/sse-client.js | 10 ++-
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 19 +++--
 3 files changed, 67 insertions(+), 42 deletions(-)

diff --git a/core/modules/server/server-sent-events.js b/core/modules/server/server-sent-events.js
index bfe7a19a8e9..fd3b3331078 100644
--- a/core/modules/server/server-sent-events.js
+++ b/core/modules/server/server-sent-events.js
@@ -3,65 +3,73 @@ title: $:/core/modules/server/server-sent-events.js
 type: application/javascript
 module-type: library
 \*/
-class ServerSentEvents {
-  /**
-   * @param {string} prefix 
-   * Usually the plugin path, such as `plugins/tiddlywiki/tiddlyweb`. 
-   * The route will match `/events/${prefix}` exactly.
-   * @param {(
-   *   request: import("http").IncomingMessage, 
-   *   state, 
-   *   emit: (event: string, data: string) => void, 
-   *   end: () => void
-   * ) => void} handler 
-   * A function that will be called each time a request 
-   * comes in with the request and state from the 
-   * route and an emit function to call.
-   */
-  constructor(prefix, handler) {
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
+/**
+ * @param {string} prefix
+ * Usually the plugin path, such as `plugins/tiddlywiki/tiddlyweb`.
+ * The route will match `/events/${prefix}` exactly.
+ * @param {(
+ *   request: import("http").IncomingMessage,
+ *   state,
+ *   emit: (event: string, data: string) => void,
+ *   end: () => void
+ * ) => void} handler
+ * A function that will be called each time a request
+ * comes in with the request and state from the
+ * route and an emit function to call.
+ */
+var ServerSentEvents = /** @class */ (function () {
+
+  function ServerSentEvents(prefix, handler) {
     this.handler = handler;
     this.prefix = prefix;
   }
-  getExports() {
+  ServerSentEvents.prototype.getExports = function () {
     return {
       bodyFormat: "stream",
       method: "GET",
       path: new RegExp("^/events/" + this.prefix + "$"),
       handler: this.handleEventRequest.bind(this)
-    }
-  }
+    };
+  };
   /**
-   * 
-   * @param {import("http").IncomingMessage} request 
-   * @param {import("http").ServerResponse} response 
-   * @param {*} state 
+   *
+   * @param {import("http").IncomingMessage} request
+   * @param {import("http").ServerResponse} response
+   * @param {*} state
    */
-  handleEventRequest(request, response, state) {
+  ServerSentEvents.prototype.handleEventRequest = function (request, response, state) {
     if (request.headers.accept && request.headers.accept.startsWith('text/event-stream')) {
       response.writeHead(200, {
         'Content-Type': 'text/event-stream',
         'Cache-Control': 'no-cache',
         'Connection': 'keep-alive'
       });
-
       this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
-    } else {
+    }
+    else {
       response.writeHead(406, "Not Acceptable", {});
       response.end();
     }
-  }
-  emit(response, event, data) {
-
+  };
+  ServerSentEvents.prototype.emit = function (response, event, data) {
     if (typeof event !== "string" || event.indexOf("\n") !== -1)
       throw new Error("type must be a single-line string");
-
     if (typeof data !== "string" || data.indexOf("\n") !== -1)
       throw new Error("data must be a single-line string");
-
-    response.write(`event: ${event}\ndata: ${data}\n\n`, "utf8");
-  }
-  end(response) {
+    response.write("event: " + event + "\ndata: " + data + "\n\n", "utf8");
+  };
+  ServerSentEvents.prototype.end = function (response) {
     response.end();
-  }
-}
+  };
+  return ServerSentEvents;
+}());
+
 exports.ServerSentEvents = ServerSentEvents;
+
+})();
\ No newline at end of file
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index 7301bf43096..6aa89caccd6 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -6,6 +6,12 @@ module-type: startup
 GET /recipes/default/tiddlers/:title
 
 \*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
 exports.name = "/events/plugins/tiddlywiki/tiddlyweb";
 exports.after = ["startup"];
 exports.synchronous = true;
@@ -15,4 +21,6 @@ exports.startup = function () {
   events.addEventListener("change", function () {
     $tw.syncer.syncFromServer();
   });
-}
\ No newline at end of file
+}
+
+})();
\ No newline at end of file
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index 0c2a1bd72e3..18c4a751185 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -6,11 +6,17 @@ module-type: route
 GET /events/plugins/tiddlywiki/tiddlyweb
 
 \*/
+(function(){
+
+/*jslint node: true, browser: true */
+/*global $tw: false */
+"use strict";
+
 var ServerSentEvents = require("$:/core/modules/server/server-sent-events.js").ServerSentEvents;
 /** @type {Record<any, {
- *   request: import("http").IncomingMessage, 
- *   state, 
- *   emit: (event: string, data: string) => void, 
+ *   request: import("http").IncomingMessage,
+ *   state,
+ *   emit: (event: string, data: string) => void,
  *   end: () => void
  * }[]>} */
 var wikis = {};
@@ -22,8 +28,11 @@ function setupWiki(wiki) {
     });
   });
 }
-var events = new ServerSentEvents("plugins/tiddlywiki/tiddlyweb", (request, state, emit, end) => {
-  if (!wikis[state.wiki]) setupWiki(state.wiki);
+var events = new ServerSentEvents("plugins/tiddlywiki/tiddlyweb", function (request, state, emit, end) {
+  if (!wikis[state.wiki])
+    setupWiki(state.wiki);
   wikis[state.wiki].push({ request: request, state: state, emit: emit, end: end });
 });
 module.exports = events.getExports();
+
+})();
\ No newline at end of file

From 85c55883274b53cf99bf037f398309f9d13dca40 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Wed, 29 Apr 2020 13:24:30 -0400
Subject: [PATCH 05/14] Use the host string from tiddlyweb

---
 plugins/tiddlywiki/tiddlyweb/sse-client.js | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index 6aa89caccd6..5f73788b427 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -17,7 +17,14 @@ exports.after = ["startup"];
 exports.synchronous = true;
 exports.platforms = ["browser"];
 exports.startup = function () {
-  var events = new EventSource("/events/plugins/tiddlywiki/tiddlyweb");
+  //make sure we're actually being used
+  if($tw.syncadaptor.name !== "tiddlyweb") return;
+  //get the mount point in case a path prefix is used
+  var host = $tw.syncadaptor.getHost();
+  //make sure it ends with a slash (it usually does)
+  if(!host.endsWith("/")) host += "/";
+  //setup the event listener 
+  var events = new EventSource(host + "events/plugins/tiddlywiki/tiddlyweb");
   events.addEventListener("change", function () {
     $tw.syncer.syncFromServer();
   });

From 63b5710f6b831dafbabefe4c64cb08792118bf3d Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Mon, 11 May 2020 20:51:51 -0400
Subject: [PATCH 06/14] Improve comments in sse-server.js

---
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 38 ++++++++++++++++++----
 1 file changed, 31 insertions(+), 7 deletions(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index 18c4a751185..9c5a9900b3b 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -12,27 +12,51 @@ GET /events/plugins/tiddlywiki/tiddlyweb
 /*global $tw: false */
 "use strict";
 
-var ServerSentEvents = require("$:/core/modules/server/server-sent-events.js").ServerSentEvents;
 /** @type {Record<any, {
  *   request: import("http").IncomingMessage,
- *   state,
+ *   state: {wiki,pathPrefix},
  *   emit: (event: string, data: string) => void,
  *   end: () => void
  * }[]>} */
 var wikis = {};
+/**
+ * Setups up the array for this wiki and adds the change listener
+ * 
+ * @param {$tw.Wiki} wiki The wiki object to listen to changes on
+ */
 function setupWiki(wiki) {
+  // add a new array for this wiki (object references work as keys)
   wikis[wiki] = [];
+  // add the change listener for this wiki
   wiki.addEventListener("change", function (changes) {
     wikis[wiki].forEach(function (item) {
       item.emit("change", JSON.stringify(changes));
     });
   });
 }
-var events = new ServerSentEvents("plugins/tiddlywiki/tiddlyweb", function (request, state, emit, end) {
-  if (!wikis[state.wiki])
-    setupWiki(state.wiki);
-  wikis[state.wiki].push({ request: request, state: state, emit: emit, end: end });
-});
+/**
+ * 
+ * @param {import("http").IncomingMessage} request 
+ * @param {{wiki,pathPrefix}} state 
+ * @param {(event: string, data: string) => void} emit 
+ * @param {() => void} end 
+ */
+function handleConnection(request, state, emit, end) {
+  // setup this particular wiki if we haven't seen it before
+  if (!wikis[state.wiki]) setupWiki(state.wiki);
+  // add the connection to the list of connections for this wiki
+  var item = { request: request, state: state, emit: emit, end: end };
+  wikis[state.wiki].push(item);
+  // remove the connection when it closes
+  request.on("close",function(){
+    wikis[state.wiki].splice(wikis[state.wiki].indexOf(item),1);
+  });
+}
+// import the ServerSentEvents class
+var ServerSentEvents = require("$:/core/modules/server/server-sent-events.js").ServerSentEvents;
+// instantiate the class
+var events = new ServerSentEvents("plugins/tiddlywiki/tiddlyweb", handleConnection);
+// export the route definition for this server sent events instance
 module.exports = events.getExports();
 
 })();
\ No newline at end of file

From 65a5daee4ce051a56230dabc8f30472dc937ff97 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Fri, 15 May 2020 09:43:39 -0400
Subject: [PATCH 07/14] Can't use object reference as key

---
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index 9c5a9900b3b..e34423eaca1 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -18,21 +18,25 @@ GET /events/plugins/tiddlywiki/tiddlyweb
  *   emit: (event: string, data: string) => void,
  *   end: () => void
  * }[]>} */
-var wikis = {};
+var wikis = [];
+var conns = [];
 /**
  * Setups up the array for this wiki and adds the change listener
  * 
  * @param {$tw.Wiki} wiki The wiki object to listen to changes on
  */
 function setupWiki(wiki) {
+  var index = wikis.length;
   // add a new array for this wiki (object references work as keys)
-  wikis[wiki] = [];
+  wikis.push(wiki);
+  conns.push([]);
   // add the change listener for this wiki
   wiki.addEventListener("change", function (changes) {
-    wikis[wiki].forEach(function (item) {
+    conns[index].forEach(function (item) {
       item.emit("change", JSON.stringify(changes));
     });
   });
+  return index;
 }
 /**
  * 
@@ -42,14 +46,15 @@ function setupWiki(wiki) {
  * @param {() => void} end 
  */
 function handleConnection(request, state, emit, end) {
+  var index = wikis.indexOf(state.wiki);
   // setup this particular wiki if we haven't seen it before
-  if (!wikis[state.wiki]) setupWiki(state.wiki);
+  if (index === -1) index = setupWiki(state.wiki);
   // add the connection to the list of connections for this wiki
   var item = { request: request, state: state, emit: emit, end: end };
-  wikis[state.wiki].push(item);
+  conns[index].push(item);
   // remove the connection when it closes
   request.on("close",function(){
-    wikis[state.wiki].splice(wikis[state.wiki].indexOf(item),1);
+    conns[index].splice(wikis[state.wiki].indexOf(item),1);
   });
 }
 // import the ServerSentEvents class

From 2632661245eae9d3da834df238273196438232d5 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Fri, 15 May 2020 12:05:36 -0400
Subject: [PATCH 08/14] Add retry timeout

---
 core/modules/server/server-sent-events.js  |  3 +--
 plugins/tiddlywiki/tiddlyweb/sse-client.js | 10 +++++++++-
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/core/modules/server/server-sent-events.js b/core/modules/server/server-sent-events.js
index fd3b3331078..00c047800d5 100644
--- a/core/modules/server/server-sent-events.js
+++ b/core/modules/server/server-sent-events.js
@@ -51,8 +51,7 @@ var ServerSentEvents = /** @class */ (function () {
         'Connection': 'keep-alive'
       });
       this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
-    }
-    else {
+    } else {
       response.writeHead(406, "Not Acceptable", {});
       response.end();
     }
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index 5f73788b427..573d7a015fc 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -24,10 +24,18 @@ exports.startup = function () {
   //make sure it ends with a slash (it usually does)
   if(!host.endsWith("/")) host += "/";
   //setup the event listener 
+  setupEvents(host);
+}
+function setupEvents(host){
   var events = new EventSource(host + "events/plugins/tiddlywiki/tiddlyweb");
   events.addEventListener("change", function () {
     $tw.syncer.syncFromServer();
   });
+  events.onerror = function() {
+    events.close();
+    setTimeout(function() { 
+      setupEvents(host); 
+    }, $tw.syncer.errorRetryInterval)
+  };
 }
-
 })();
\ No newline at end of file

From e8d62fe5571df9a8c0d62b0798ad79678de9ffe3 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Wed, 20 May 2020 17:47:59 -0400
Subject: [PATCH 09/14] Fix a bug

---
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index e34423eaca1..e54470693ca 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -12,13 +12,14 @@ GET /events/plugins/tiddlywiki/tiddlyweb
 /*global $tw: false */
 "use strict";
 
-/** @type {Record<any, {
+/** @type {any[]} */
+var wikis = [];
+/** @type {{
  *   request: import("http").IncomingMessage,
  *   state: {wiki,pathPrefix},
  *   emit: (event: string, data: string) => void,
  *   end: () => void
- * }[]>} */
-var wikis = [];
+ * }[][]} */
 var conns = [];
 /**
  * Setups up the array for this wiki and adds the change listener
@@ -54,7 +55,8 @@ function handleConnection(request, state, emit, end) {
   conns[index].push(item);
   // remove the connection when it closes
   request.on("close",function(){
-    conns[index].splice(wikis[state.wiki].indexOf(item),1);
+    var remIndex = wikis[index].indexOf(item);
+    if(remIndex > -1) conns[index].splice(remIndex,1);
   });
 }
 // import the ServerSentEvents class

From 06009b04d9d03fcd9ee845246bc02faef908ee22 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Sat, 23 May 2020 13:31:55 -0400
Subject: [PATCH 10/14] bug fix

---
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index e54470693ca..43a787465d8 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -28,12 +28,13 @@ var conns = [];
  */
 function setupWiki(wiki) {
   var index = wikis.length;
+  var connections = [];
   // add a new array for this wiki (object references work as keys)
   wikis.push(wiki);
-  conns.push([]);
+  conns.push(connections);
   // add the change listener for this wiki
   wiki.addEventListener("change", function (changes) {
-    conns[index].forEach(function (item) {
+    connections.forEach(function (item) {
       item.emit("change", JSON.stringify(changes));
     });
   });
@@ -55,7 +56,7 @@ function handleConnection(request, state, emit, end) {
   conns[index].push(item);
   // remove the connection when it closes
   request.on("close",function(){
-    var remIndex = wikis[index].indexOf(item);
+    var remIndex = conns[index].indexOf(item);
     if(remIndex > -1) conns[index].splice(remIndex,1);
   });
 }

From b861b5886682a9ff46e1635dc76c082d9d3650ff Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Thu, 29 Oct 2020 14:31:17 -0400
Subject: [PATCH 11/14] Fix formatting

---
 core/modules/server/server-sent-events.js  | 84 +++++++++++-----------
 plugins/tiddlywiki/tiddlyweb/sse-client.js | 10 ++-
 plugins/tiddlywiki/tiddlyweb/sse-server.js |  4 +-
 3 files changed, 51 insertions(+), 47 deletions(-)

diff --git a/core/modules/server/server-sent-events.js b/core/modules/server/server-sent-events.js
index 00c047800d5..088d8522169 100644
--- a/core/modules/server/server-sent-events.js
+++ b/core/modules/server/server-sent-events.js
@@ -23,52 +23,52 @@ module-type: library
  * comes in with the request and state from the
  * route and an emit function to call.
  */
-var ServerSentEvents = /** @class */ (function () {
+var ServerSentEvents = function ServerSentEvents(prefix, handler) {
+  this.handler = handler;
+  this.prefix = prefix;
+}
 
-  function ServerSentEvents(prefix, handler) {
-    this.handler = handler;
-    this.prefix = prefix;
-  }
-  ServerSentEvents.prototype.getExports = function () {
-    return {
-      bodyFormat: "stream",
-      method: "GET",
-      path: new RegExp("^/events/" + this.prefix + "$"),
-      handler: this.handleEventRequest.bind(this)
-    };
-  };
-  /**
-   *
-   * @param {import("http").IncomingMessage} request
-   * @param {import("http").ServerResponse} response
-   * @param {*} state
-   */
-  ServerSentEvents.prototype.handleEventRequest = function (request, response, state) {
-    if (request.headers.accept && request.headers.accept.startsWith('text/event-stream')) {
-      response.writeHead(200, {
-        'Content-Type': 'text/event-stream',
-        'Cache-Control': 'no-cache',
-        'Connection': 'keep-alive'
-      });
-      this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
-    } else {
-      response.writeHead(406, "Not Acceptable", {});
-      response.end();
-    }
-  };
-  ServerSentEvents.prototype.emit = function (response, event, data) {
-    if (typeof event !== "string" || event.indexOf("\n") !== -1)
-      throw new Error("type must be a single-line string");
-    if (typeof data !== "string" || data.indexOf("\n") !== -1)
-      throw new Error("data must be a single-line string");
-    response.write("event: " + event + "\ndata: " + data + "\n\n", "utf8");
+ServerSentEvents.prototype.getExports = function() {
+  return {
+    bodyFormat: "stream",
+    method: "GET",
+    path: new RegExp("^/events/" + this.prefix + "$"),
+    handler: this.handleEventRequest.bind(this)
   };
-  ServerSentEvents.prototype.end = function (response) {
+};
+
+/**
+ *
+ * @param {import("http").IncomingMessage} request
+ * @param {import("http").ServerResponse} response
+ * @param {*} state
+ */
+ServerSentEvents.prototype.handleEventRequest = function(request, response, state) {
+  if (request.headers.accept && request.headers.accept.startsWith('text/event-stream')) {
+    response.writeHead(200, {
+      'Content-Type': 'text/event-stream',
+      'Cache-Control': 'no-cache',
+      'Connection': 'keep-alive'
+    });
+    this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
+  } else {
+    response.writeHead(406, "Not Acceptable", {});
     response.end();
-  };
-  return ServerSentEvents;
-}());
+  }
+};
+
+ServerSentEvents.prototype.emit = function(response, event, data) {
+  if (typeof event !== "string" || event.indexOf("\n") !== -1)
+    throw new Error("type must be a single-line string");
+  if (typeof data !== "string" || data.indexOf("\n") !== -1)
+    throw new Error("data must be a single-line string");
+  response.write("event: " + event + "\ndata: " + data + "\n\n", "utf8");
+};
 
+ServerSentEvents.prototype.end = function(response) {
+  response.end();
+};
+  
 exports.ServerSentEvents = ServerSentEvents;
 
 })();
\ No newline at end of file
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index 573d7a015fc..31f820cb4d2 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -16,7 +16,7 @@ exports.name = "/events/plugins/tiddlywiki/tiddlyweb";
 exports.after = ["startup"];
 exports.synchronous = true;
 exports.platforms = ["browser"];
-exports.startup = function () {
+exports.startup = function() {
   //make sure we're actually being used
   if($tw.syncadaptor.name !== "tiddlyweb") return;
   //get the mount point in case a path prefix is used
@@ -28,8 +28,12 @@ exports.startup = function () {
 }
 function setupEvents(host){
   var events = new EventSource(host + "events/plugins/tiddlywiki/tiddlyweb");
-  events.addEventListener("change", function () {
-    $tw.syncer.syncFromServer();
+  var timeout = null;
+  events.addEventListener("change", function() {
+    if(timeout) clearTimeout(timeout);
+    timeout = setTimeout(function(){
+      $tw.syncer.syncFromServer();
+    }, $tw.syncer.throttleInterval);
   });
   events.onerror = function() {
     events.close();
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index 43a787465d8..a1207ea189d 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -33,8 +33,8 @@ function setupWiki(wiki) {
   wikis.push(wiki);
   conns.push(connections);
   // add the change listener for this wiki
-  wiki.addEventListener("change", function (changes) {
-    connections.forEach(function (item) {
+  wiki.addEventListener("change", function(changes) {
+    connections.forEach(function(item) {
       item.emit("change", JSON.stringify(changes));
     });
   });

From 5fb2c5cd88967e57894bf8397cc7acb003c3f761 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Thu, 29 Oct 2020 14:33:50 -0400
Subject: [PATCH 12/14] Fix ES5 compat

---
 plugins/tiddlywiki/tiddlyweb/sse-client.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index 31f820cb4d2..1e57dbfa89c 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -22,7 +22,7 @@ exports.startup = function() {
   //get the mount point in case a path prefix is used
   var host = $tw.syncadaptor.getHost();
   //make sure it ends with a slash (it usually does)
-  if(!host.endsWith("/")) host += "/";
+  if(host[host.length - 1] !== "/") host += "/";
   //setup the event listener 
   setupEvents(host);
 }

From eed4c1829486e5c93345b3b18b7c35b03385081a Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Thu, 29 Oct 2020 14:35:14 -0400
Subject: [PATCH 13/14] capitalize comments

---
 plugins/tiddlywiki/tiddlyweb/sse-client.js | 8 ++++----
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 6 +++---
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index 1e57dbfa89c..a9819eceb63 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -17,13 +17,13 @@ exports.after = ["startup"];
 exports.synchronous = true;
 exports.platforms = ["browser"];
 exports.startup = function() {
-  //make sure we're actually being used
+  // Make sure we're actually being used
   if($tw.syncadaptor.name !== "tiddlyweb") return;
-  //get the mount point in case a path prefix is used
+  // Get the mount point in case a path prefix is used
   var host = $tw.syncadaptor.getHost();
-  //make sure it ends with a slash (it usually does)
+  // Make sure it ends with a slash (it usually does)
   if(host[host.length - 1] !== "/") host += "/";
-  //setup the event listener 
+  // Setup the event listener 
   setupEvents(host);
 }
 function setupEvents(host){
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index a1207ea189d..c03d0085ab4 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -60,11 +60,11 @@ function handleConnection(request, state, emit, end) {
     if(remIndex > -1) conns[index].splice(remIndex,1);
   });
 }
-// import the ServerSentEvents class
+// Import the ServerSentEvents class
 var ServerSentEvents = require("$:/core/modules/server/server-sent-events.js").ServerSentEvents;
-// instantiate the class
+// Instantiate the class
 var events = new ServerSentEvents("plugins/tiddlywiki/tiddlyweb", handleConnection);
-// export the route definition for this server sent events instance
+// Export the route definition for this server sent events instance
 module.exports = events.getExports();
 
 })();
\ No newline at end of file

From 2264946bb4d5cd2181f782b617adf38825613ca8 Mon Sep 17 00:00:00 2001
From: Arlen22 <arlenbee@gmail.com>
Date: Thu, 29 Oct 2020 14:41:22 -0400
Subject: [PATCH 14/14] more fixes

---
 core/modules/server/server-sent-events.js  | 18 ++++++++++--------
 plugins/tiddlywiki/tiddlyweb/sse-client.js |  1 +
 plugins/tiddlywiki/tiddlyweb/sse-server.js | 12 +++++++-----
 3 files changed, 18 insertions(+), 13 deletions(-)

diff --git a/core/modules/server/server-sent-events.js b/core/modules/server/server-sent-events.js
index 088d8522169..061f1182d27 100644
--- a/core/modules/server/server-sent-events.js
+++ b/core/modules/server/server-sent-events.js
@@ -44,11 +44,11 @@ ServerSentEvents.prototype.getExports = function() {
  * @param {*} state
  */
 ServerSentEvents.prototype.handleEventRequest = function(request, response, state) {
-  if (request.headers.accept && request.headers.accept.startsWith('text/event-stream')) {
+  if(request.headers.accept && request.headers.accept.startsWith("text/event-stream")) {
     response.writeHead(200, {
-      'Content-Type': 'text/event-stream',
-      'Cache-Control': 'no-cache',
-      'Connection': 'keep-alive'
+      "Content-Type": "text/event-stream",
+      "Cache-Control": "no-cache",
+      "Connection": "keep-alive"
     });
     this.handler(request, state, this.emit.bind(this, response), this.end.bind(this, response));
   } else {
@@ -58,10 +58,12 @@ ServerSentEvents.prototype.handleEventRequest = function(request, response, stat
 };
 
 ServerSentEvents.prototype.emit = function(response, event, data) {
-  if (typeof event !== "string" || event.indexOf("\n") !== -1)
-    throw new Error("type must be a single-line string");
-  if (typeof data !== "string" || data.indexOf("\n") !== -1)
-    throw new Error("data must be a single-line string");
+  if(typeof event !== "string" || event.indexOf("\n") !== -1) {
+    throw new Error("Type must be a single-line string");
+  }
+  if(typeof data !== "string" || data.indexOf("\n") !== -1) {
+    throw new Error("Data must be a single-line string");
+  }
   response.write("event: " + event + "\ndata: " + data + "\n\n", "utf8");
 };
 
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-client.js b/plugins/tiddlywiki/tiddlyweb/sse-client.js
index a9819eceb63..a8639f8e3d3 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-client.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-client.js
@@ -26,6 +26,7 @@ exports.startup = function() {
   // Setup the event listener 
   setupEvents(host);
 }
+
 function setupEvents(host){
   var events = new EventSource(host + "events/plugins/tiddlywiki/tiddlyweb");
   var timeout = null;
diff --git a/plugins/tiddlywiki/tiddlyweb/sse-server.js b/plugins/tiddlywiki/tiddlyweb/sse-server.js
index c03d0085ab4..129b19f6936 100644
--- a/plugins/tiddlywiki/tiddlyweb/sse-server.js
+++ b/plugins/tiddlywiki/tiddlyweb/sse-server.js
@@ -29,10 +29,10 @@ var conns = [];
 function setupWiki(wiki) {
   var index = wikis.length;
   var connections = [];
-  // add a new array for this wiki (object references work as keys)
+  // Add a new array for this wiki (object references work as keys)
   wikis.push(wiki);
   conns.push(connections);
-  // add the change listener for this wiki
+  // Add the change listener for this wiki
   wiki.addEventListener("change", function(changes) {
     connections.forEach(function(item) {
       item.emit("change", JSON.stringify(changes));
@@ -40,6 +40,7 @@ function setupWiki(wiki) {
   });
   return index;
 }
+
 /**
  * 
  * @param {import("http").IncomingMessage} request 
@@ -49,17 +50,18 @@ function setupWiki(wiki) {
  */
 function handleConnection(request, state, emit, end) {
   var index = wikis.indexOf(state.wiki);
-  // setup this particular wiki if we haven't seen it before
+  // Setup this particular wiki if we haven't seen it before
   if (index === -1) index = setupWiki(state.wiki);
-  // add the connection to the list of connections for this wiki
+  // Add the connection to the list of connections for this wiki
   var item = { request: request, state: state, emit: emit, end: end };
   conns[index].push(item);
-  // remove the connection when it closes
+  // Remove the connection when it closes
   request.on("close",function(){
     var remIndex = conns[index].indexOf(item);
     if(remIndex > -1) conns[index].splice(remIndex,1);
   });
 }
+
 // Import the ServerSentEvents class
 var ServerSentEvents = require("$:/core/modules/server/server-sent-events.js").ServerSentEvents;
 // Instantiate the class