create session class and refactor js to use it

client/javascript/ftp.js

@@ -27,7 +27,7 @@ class FTPSession {
       };
       let headers_callback = () => {this.headers_callback()};
 
-      http_handle = create_handle(url, data_callback, finish_callback, headers_callback);
+      http_handle = create_request(url, data_callback, finish_callback, headers_callback);
       _ftp_set_options(http_handle, url, 1);
       start_request(http_handle);
     });

client/javascript/http.js

@@ -0,0 +1,141 @@
+class HTTPSession extends CurlSession {
+  constructor() {
+    super();
+    this.set_connections(50, 40);
+  }
+
+  request_async(url, params, body) {
+    return new Promise((resolve, reject) => {
+      let stream_controller;
+      let http_handle;
+      let response_obj;
+      let aborted = false;
+  
+      //handle abort signals
+      if (params.signal instanceof AbortSignal) {
+        params.signal.addEventListener("abort", () => {
+          if (aborted) return;
+          aborted = true;
+          _cleanup_handle(http_handle);
+          if (!response_obj) {
+            reject(new DOMException("The operation was aborted."));
+          }
+          else {
+            stream_controller.error("The operation was aborted.");
+          }
+        });
+      }
+  
+      let stream = new ReadableStream({
+        start(controller) {
+          stream_controller = controller;
+        }
+      });
+      
+      let data_callback = (new_data) => {
+        try {
+          stream_controller.enqueue(new_data);  
+        }
+        catch (e) {
+          //the readable stream has been closed elsewhere, so cancel the request
+          if (e instanceof TypeError) {
+            _cleanup_handle(http_handle);
+          }
+          else {
+            throw e;
+          }
+        }
+      }
+      let headers_callback = () => {
+        let response_json = c_func_str(_http_get_info, [http_handle]);
+        response_obj = this.constructor.create_response(stream, JSON.parse(response_json));
+        resolve(response_obj);
+      }
+      let finish_callback = (error) => {
+        if (error != 0) {
+          error_msg(`Request "${url}" failed with error code ${error}: ${get_error_str(error)}`);
+          reject(`Request failed with error code ${error}: ${get_error_str(error)}`);
+        }
+        try {
+          stream_controller.close();
+        } //this will only fail if the stream is already errored or closed, which isn't a problem
+        catch {}
+        this.remove_request(http_handle);
+      }
+  
+      let body_length = body ? body.length : 0;
+      let params_json = JSON.stringify(params);
+      
+      http_handle = this.create_request(url, data_callback, finish_callback, headers_callback);
+      c_func(_http_set_options, [http_handle, params_json, body, body_length]);
+      this.start_request(http_handle);
+    });
+  }
+
+  async fetch(url, params={}) {
+    let body = await this.constructor.create_options(params);
+    return await this.request_async(url, params, body);
+  }
+
+  static create_response(response_data, response_info) {
+    response_info.ok = response_info.status >= 200 && response_info.status < 300;
+    response_info.statusText = status_messages[response_info.status] || "";
+    if (response_info.status === 204 || response_info.status === 205) {
+      response_data = null;
+    }
+
+    //construct base response object
+    let response_obj = new Response(response_data, response_info);
+    for (let key in response_info) {
+      if (key == "headers") continue;
+      Object.defineProperty(response_obj, key, {
+        writable: false,
+        value: response_info[key]
+      });
+    }
+
+    //create headers object
+    Object.defineProperty(response_obj, "headers", {
+      writable: false,
+      value: new Headers()
+    });
+    Object.defineProperty(response_obj, "raw_headers", {
+      writable: false,
+      value: response_info.headers
+    });
+    for (let [header_name, header_value] of response_info.headers) {
+      response_obj.headers.append(header_name, header_value);
+    }
+    
+    return response_obj;
+  }
+
+  static async create_options(params) {
+    let body = null;
+    let request_obj = new Request("/", params);
+    let array_buffer = await request_obj.arrayBuffer();
+    if (array_buffer.byteLength > 0) {
+      body = new Uint8Array(array_buffer);
+    }
+    
+    let headers = params.headers || {};
+    if (params.headers instanceof Headers) {
+      for(let [key, value] of headers) {
+        headers[key] = value;
+      }
+    }
+    params.headers = new HeadersDict(headers);
+
+    if (params.referrer) {
+      params.headers["Referer"] = params.referrer;
+    }
+    if (!params.headers["User-Agent"]) {
+      params.headers["User-Agent"] = navigator.userAgent;
+    }
+    if (body) {
+      params.headers["Content-Type"] = request_obj.headers.get("Content-Type");
+    }
+
+    return body;
+  }
+}

client/javascript/main.js

@@ -26,11 +26,10 @@ const libcurl = (function() {
 /* __extra_libraries__ */
 
 var websocket_url = null;
-var event_loop = null;
-var active_requests = 0;
 var wasm_ready = false;
 var version_dict = null;
 var api = null;
+var main_session = null;
 const libcurl_version = "__library_version__";
 const wisp_version = "__wisp_version__";
 
@@ -43,118 +42,6 @@ function check_loaded(check_websocket) {
   }
 }
 
-function create_handle(url, js_data_callback, js_end_callback, js_headers_callback) {
-  let end_callback_ptr;
-  let data_callback_ptr;
-  let headers_callback_ptr;
-
-  function end_callback(error) {
-    Module.removeFunction(end_callback_ptr);
-    Module.removeFunction(data_callback_ptr);
-    Module.removeFunction(headers_callback_ptr);
-    
-    active_requests --;
-    js_end_callback(error);
-  }
-
-  function data_callback(chunk_ptr, chunk_size) {
-    let data = Module.HEAPU8.subarray(chunk_ptr, chunk_ptr + chunk_size);
-    let chunk = new Uint8Array(data);
-    js_data_callback(chunk);
-  }
-
-  function headers_callback() {
-    js_headers_callback();
-  }
-
-  end_callback_ptr = Module.addFunction(end_callback, "vi");
-  headers_callback_ptr = Module.addFunction(headers_callback, "v");
-  data_callback_ptr = Module.addFunction(data_callback, "vii");
-  let http_handle = c_func(_create_handle, [url, data_callback_ptr, end_callback_ptr, headers_callback_ptr]);
-  
-  return http_handle;
-}
-
-function start_request(http_handle) {
-  _start_request(http_handle);
-  _tick_request();
-  active_requests ++;
-
-  if (!event_loop) {
-    event_loop = setInterval(() => {
-      if (_active_requests() || active_requests) {
-        _tick_request();
-      }
-      else {
-        clearInterval(event_loop);
-        event_loop = null;
-      }
-    }, 0);
-  }
-}
-
-function create_response(response_data, response_info) {
-  response_info.ok = response_info.status >= 200 && response_info.status < 300;
-  response_info.statusText = status_messages[response_info.status] || "";
-  if (response_info.status === 204 || response_info.status === 205) {
-    response_data = null;
-  }
-
-  //construct base response object
-  let response_obj = new Response(response_data, response_info);
-  for (let key in response_info) {
-    if (key == "headers") continue;
-    Object.defineProperty(response_obj, key, {
-      writable: false,
-      value: response_info[key]
-    });
-  }
-
-  //create headers object
-  Object.defineProperty(response_obj, "headers", {
-    writable: false,
-    value: new Headers()
-  });
-  Object.defineProperty(response_obj, "raw_headers", {
-    writable: false,
-    value: response_info.headers
-  });
-  for (let [header_name, header_value] of response_info.headers) {
-    response_obj.headers.append(header_name, header_value);
-  }
-  
-  return response_obj;
-}
-
-async function create_options(params) {
-  let body = null;
-  let request_obj = new Request("/", params);
-  let array_buffer = await request_obj.arrayBuffer();
-  if (array_buffer.byteLength > 0) {
-    body = new Uint8Array(array_buffer);
-  }
-  
-  let headers = params.headers || {};
-  if (params.headers instanceof Headers) {
-    for(let [key, value] of headers) {
-      headers[key] = value;
-    }
-  }
-  params.headers = new HeadersDict(headers);
-
-  if (params.referrer) {
-    params.headers["Referer"] = params.referrer;
-  }
-  if (!params.headers["User-Agent"]) {
-    params.headers["User-Agent"] = navigator.userAgent;
-  }
-  if (body) {
-    params.headers["Content-Type"] = request_obj.headers.get("Content-Type");
-  }
-
-  return body;
-}
-
 //wrap perform_request in a promise
 function perform_request_async(url, params, body) {
   return new Promise((resolve, reject) => {
@@ -218,7 +105,7 @@ function perform_request_async(url, params, body) {
     let body_length = body ? body.length : 0;
     let params_json = JSON.stringify(params);
     
-    http_handle = create_handle(url, data_callback, finish_callback, headers_callback);
+    http_handle = create_request(url, data_callback, finish_callback, headers_callback);
     c_func(_http_set_options, [http_handle, params_json, body, body_length]);
     start_request(http_handle);
   });
@@ -263,6 +150,10 @@ function main() {
     let load_event = new Event("libcurl_load");
     document.dispatchEvent(load_event);
   }
+
+  main_session = new HTTPSession();
+  api.fetch = main_session.fetch.bind(main_session);
+
   api.onload();
 }
 
@@ -274,18 +165,19 @@ function load_wasm(url) {
 
 Module.onRuntimeInitialized = main;
 api = {
-  fetch: libcurl_fetch,
   set_websocket: set_websocket_url,
   load_wasm: load_wasm,
-  WebSocket: FakeWebSocket,
-  CurlWebSocket: CurlWebSocket,
-  TLSSocket: TLSSocket,
   get_cacert: get_cacert,
   get_error_string: get_error_str,
 
   wisp_connections: _wisp_connections,
   WispConnection: WispConnection,
   transport: "wisp",
+
+  WebSocket: WebSocket,
+  CurlWebSocket: CurlWebSocket,
+  TLSSocket: TLSSocket,
+  fetch: () => {throw "not ready"},
   
   get copyright() {return copyright_notice},
   get version() {return get_version()},

client/javascript/session.js

@@ -0,0 +1,98 @@
+class CurlSession {
+  constructor(options={}) {
+    check_loaded(true);
+
+    this.options = options;
+    this.session_ptr = _session_create();
+    this.active_requests = 0;
+    this.event_loop = null;
+    this.requests_list = [];
+  }
+
+  assert_ready() {
+    if (!this.session_ptr) {
+      throw "session has been removed";
+    }
+  }
+
+  set_connections(connections_limit, cache_limit) {
+    this.assert_ready();
+    _session_set_options(this.session_ptr, connections_limit, cache_limit);
+  }
+
+  create_request(url, js_data_callback, js_end_callback, js_headers_callback) {
+    this.assert_ready();
+    let end_callback_ptr;
+    let data_callback_ptr;
+    let headers_callback_ptr;
+  
+    let end_callback = (error) => {
+      Module.removeFunction(end_callback_ptr);
+      Module.removeFunction(data_callback_ptr);
+      Module.removeFunction(headers_callback_ptr);
+      
+      this.active_requests--;
+      js_end_callback(error);
+    }
+  
+    let data_callback = (chunk_ptr, chunk_size) => {
+      let data = Module.HEAPU8.subarray(chunk_ptr, chunk_ptr + chunk_size);
+      let chunk = new Uint8Array(data);
+      js_data_callback(chunk);
+    }
+  
+    let headers_callback = () => {
+      js_headers_callback();
+    }
+  
+    end_callback_ptr = Module.addFunction(end_callback, "vi");
+    headers_callback_ptr = Module.addFunction(headers_callback, "v");
+    data_callback_ptr = Module.addFunction(data_callback, "vii");
+    let request_ptr = c_func(_create_request, [url, data_callback_ptr, end_callback_ptr, headers_callback_ptr]);
+    
+    return request_ptr;
+  }
+
+  remove_request(request_ptr) {
+    this.assert_ready();
+    _session_remove_request(this.session_ptr, request_ptr);
+
+    let request_index = this.requests_list.indexOf(request_ptr);
+    if (request_index !== -1) {
+      this.requests_list.splice(request_index, 1);
+    }
+  }
+
+  start_request(request_ptr) {
+    this.assert_ready();
+    _session_add_request(this.session_ptr, request_ptr);
+    _session_perform(this.session_ptr);
+
+    this.active_requests++;
+    this.requests_list.push(request_ptr);
+  
+    if (this.event_loop) {
+      return;
+    }
+    
+    this.event_loop = setInterval(() => {
+      let libcurl_active = _session_get_active(this.session_ptr);
+      if (libcurl_active || this.active_requests) {
+        _session_perform(this.session_ptr);
+      }
+      else {
+        clearInterval(this.event_loop);
+        this.event_loop = null;
+      }
+    }, 0);
+  }
+
+  close() {
+    this.assert_ready();
+    for (let request_ptr of this.requests_list) {
+      this.remove_request(request_ptr);
+    }
+    _session_cleanup(this.session_ptr);
+    this.session_ptr = null;
+  }
+}

client/javascript/tls_socket.js

@@ -1,8 +1,8 @@
 //currently broken
 
-class TLSSocket {
+class TLSSocket extends CurlSession {
   constructor(hostname, port, options={}) {
-    check_loaded(true);
+    super();
 
     this.hostname = hostname;
     this.port = port;
@@ -15,8 +15,9 @@ class TLSSocket {
     this.onclose = () => {};
 
     this.connected = false;
-    this.event_loop = null;
+    this.recv_loop = null;
 
+    this.set_connections(1, 0);
     this.connect();
   }
 
@@ -29,7 +30,7 @@ class TLSSocket {
     let finish_callback = (error) => {
       if (error === 0) {
         this.connected = true;
-        this.event_loop = setInterval(() => {
+        this.recv_loop = setInterval(() => {
           let data = this.recv();
           if (data != null) this.onmessage(data);
         }, 0);
@@ -40,9 +41,9 @@ class TLSSocket {
       }
     }
 
-    this.http_handle = create_handle(this.url, data_callback, finish_callback, headers_callback);
+    this.http_handle = this.create_request(this.url, data_callback, finish_callback, headers_callback);
     _tls_socket_set_options(this.http_handle, +this.options.verbose);
-    start_request(this.http_handle);
+    this.start_request(this.http_handle);
   }
 
   recv() {
@@ -80,10 +81,14 @@ class TLSSocket {
   }
 
   cleanup(error=false) {
-    if (this.http_handle) _cleanup_handle(this.http_handle);
+    if (this.http_handle) {
+      this.remove_request(this.http_handle);
+      this.http_handle = null;
+      super.close();
+    }
     else return;
     
-    clearInterval(this.event_loop);
+    clearInterval(this.recv_loop);
     this.connected = false;
 
     if (error) {

client/javascript/websocket.js

@@ -1,9 +1,9 @@
-class CurlWebSocket {
-  constructor(url, protocols=[], options={}) {
-    check_loaded(true);
+class CurlWebSocket extends CurlSession {
+  constructor(url, protocols=[], options={}) {    
     if (!url.startsWith("wss://") && !url.startsWith("ws://")) {
       throw new SyntaxError("invalid url");
     }
+    super();
     
     this.url = url;
     this.protocols = protocols;
@@ -15,9 +15,11 @@ class CurlWebSocket {
     this.onclose = () => {};
 
     this.connected = false;
-    this.event_loop = null;
+    this.recv_loop = null;
+    this.http_handle = null;
     this.recv_buffer = [];
 
+    this.set_connections(1, 0);
     this.connect();
   }
 
@@ -27,7 +29,7 @@ class CurlWebSocket {
     let finish_callback = (error) => {
       if (error === 0) {
         this.connected = true;
-        this.event_loop = setInterval(() => {
+        this.recv_loop = setInterval(() => {
           let data = this.recv();
           if (data !== null) this.onmessage(data);
         }, 0);
@@ -47,10 +49,10 @@ class CurlWebSocket {
       request_options._libcurl_verbose = 1;
     }
 
-    this.http_handle = create_handle(this.url, data_callback, finish_callback, headers_callback);
+    this.http_handle = this.create_request(this.url, data_callback, finish_callback, headers_callback);
     c_func(_http_set_options, [this.http_handle, JSON.stringify(request_options), null, 0]);
     _websocket_set_options(this.http_handle);
-    start_request(this.http_handle);
+    this.start_request(this.http_handle);
   }
 
   recv() {
@@ -104,10 +106,14 @@ class CurlWebSocket {
   }
 
   cleanup(error=0) {
-    if (this.http_handle) _cleanup_handle(this.http_handle);
+    if (this.http_handle) {
+      this.remove_handle(this.http_handle);
+      this.http_handle = null;
+      super.close();
+    }
     else return;
 
-    clearInterval(this.event_loop);
+    clearInterval(this.recv_loop);
     this.connected = false;
 
     if (error) {