Bug 1719414 - Init NntpClient.jsm to interact with NNTP server. r=mkmelin

Depends on D119594.

Differential Revision: https://phabricator.services.mozilla.com/D119595

--HG--
extra : amend_source : ef03e9baa305539684da74e34296e64ad9f39bf1

mailnews/news/src/NntpClient.jsm

@@ -0,0 +1,208 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const EXPORTED_SYMBOLS = ["NntpClient"];
+
+var { CommonUtils } = ChromeUtils.import("resource://services-common/utils.js");
+
+/**
+ * A structure to represent a response received from the server. A response can
+ * be a single status line of a multi-line data block.
+ * @typedef {Object} NntpResponse
+ * @property {number} status - The status code of the response.
+ * @property {string} statusText - The status line of the response excluding the
+ *   status code.
+ * @property {string} data - The part of a multi-line data block excluding the
+ *   status line.
+ */
+
+/**
+ * A class to interact with NNTP server.
+ */
+class NntpClient {
+  /**
+   * @param {nsINntpIncomingServer} server - The associated server instance.
+   * @param {string} uri - The server uri.
+   */
+  constructor(server, uri) {
+    this.onOpen = () => {};
+    this.onError = () => {};
+
+    this._server = server;
+    let matches = /.+:\/\/(.+)\/(.+)/.exec(uri);
+    this._host = matches[1];
+    this._group = matches[2];
+
+    this._logger = console.createInstance({
+      prefix: "mailnews.nntp",
+      maxLogLevel: "Warn",
+      maxLogLevelPref: "mailnews.nntp.loglevel",
+    });
+  }
+
+  /**
+   * Initiate a connection to the server
+   */
+  connect() {
+    let port = this._server.port;
+    let useSecureTransport = this._server.isSecure;
+    this._logger.debug(
+      `Connecting to ${useSecureTransport ? "snews" : "news"}://${
+        this._host
+      }:${port}`
+    );
+    this._socket = new TCPSocket(this._host, port, {
+      binaryType: "arraybuffer",
+      useSecureTransport,
+    });
+    this._socket.onopen = this._onOpen;
+    this._socket.onerror = this._onError;
+  }
+
+  /**
+   * The open event handler.
+   */
+  _onOpen = () => {
+    this._logger.debug("Connected");
+    this._socket.ondata = this._onData;
+    this._socket.onclose = this._onClose;
+    this.onOpen();
+  };
+
+  /**
+   * The data event handler.
+   * @param {TCPSocketEvent} event - The data event.
+   */
+  _onData = event => {
+    let stringPayload = CommonUtils.arrayBufferToByteString(
+      new Uint8Array(event.data)
+    );
+    this._logger.debug(`S: ${stringPayload}`);
+
+    let res = this._parse(stringPayload);
+
+    this._nextAction?.(res);
+  };
+
+  /**
+   * Parse the server response.
+   * @param {string} str - Response received from the server.
+   * @returns {NntpResponse}
+   */
+  _parse(str) {
+    let matches = /^(\d{3}) (.+)\r\n([^]*)/.exec(str);
+    if (matches) {
+      let [, status, statusText, data] = matches;
+      return { status: Number(status), statusText, data };
+    }
+    return { data: str };
+  }
+
+  /**
+   * Send a string to the socket.
+   * @param {string} str - The string to send.
+   */
+  _sendString(str) {
+    this._logger.debug(`C: ${str}`);
+    this._socket.send(CommonUtils.byteStringToArrayBuffer(str + "\r\n").buffer);
+  }
+
+  /**
+   * Get new articles.
+   * @param {boolean} getOld - Get old articles as well.
+   * @param {nsIUrlListener} urlListener - Callback for the request.
+   * @param {nsIMsgWindow} msgWindow - The associated msg window.
+   */
+  getNewNews(getOld, urlListener, msgWindow) {
+    this._nextAction = this._actionModeReader;
+  }
+
+  /**
+   * Send `MODE READER` request to the server.
+   */
+  _actionModeReader() {
+    this._sendString("MODE READER");
+    this._nextAction = this._actionGroup;
+  }
+
+  /**
+   * Send `GROUP` request to the server.
+   */
+  _actionGroup() {
+    this._sendString(`GROUP ${this._group}`);
+    this._nextAction = this._actionXOver;
+  }
+
+  /**
+   * Send `XOVER` request to the server.
+   */
+  _actionXOver(res) {
+    let [, , high] = res.statusText.split(" ");
+    // TODO figure out the range, which depends on the folder state and user
+    // settings.
+    this._sendString(`XOVER ${high - 10}-${high}`);
+    this._nextAction = this._actionXOverResponse;
+  }
+
+  /**
+   * A transient action to consume the status line of XOVER response.
+   * @param {NntpResponse} res - XOVER response received from the server.
+   */
+  _actionXOverResponse(res) {
+    this._actionReadXOver(res);
+    this._nextAction = this._actionReadXOver;
+  }
+
+  /**
+   * Handle XOVER response.
+   * @param {NntpResponse} res - XOVER response received from the server.
+   */
+  _actionReadXOver({ data }) {
+    // XOVER response can span multiple ondata events, an event's leftover data
+    // is saved in this._xoverData.
+    if (this._xoverData) {
+      data = this._xoverData + data;
+      this._xoverData = null;
+    }
+    while (data) {
+      let index = data.indexOf("\r\n");
+      if (index == -1) {
+        // Not enough data, save it for the next round.
+        this._xoverData = data;
+        break;
+      }
+      if (data == ".\r\n") {
+        // Finished reading XOVER response.
+        this._nextAction = null;
+        break;
+      }
+      let parts = data.slice(0, index).split("\t");
+      if (parts.length >= 8) {
+        let [
+          articleNumber,
+          subject,
+          from,
+          date,
+          messageId,
+          references,
+          bytes,
+          lines,
+          ...extra
+        ] = parts;
+        this._logger.debug({
+          articleNumber,
+          subject,
+          from,
+          date,
+          messageId,
+          references,
+          bytes,
+          lines,
+          extra,
+        });
+      }
+      data = data.slice(index + 2);
+    }
+  }
+}

mailnews/news/src/NntpService.jsm

@@ -4,6 +4,14 @@
 
 const EXPORTED_SYMBOLS = ["NntpService"];
 
+const { XPCOMUtils } = ChromeUtils.import(
+  "resource://gre/modules/XPCOMUtils.jsm"
+);
+
+XPCOMUtils.defineLazyModuleGetters(this, {
+  NntpClient: "resource:///modules/NntpClient.jsm",
+});
+
 /**
  * Set the mailnews.nntp.jsmodule pref to true to use this module.
  *
@@ -12,7 +20,14 @@ const EXPORTED_SYMBOLS = ["NntpService"];
 class NntpService {
   QueryInterface = ChromeUtils.generateQI(["nsINntpService"]);
 
-  getNewNews(server, uri, getOld, urlListener, msgWindow) {}
+  getNewNews(server, uri, getOld, urlListener, msgWindow) {
+    let client = new NntpClient(server, uri);
+    client.connect();
+
+    client.onOpen = () => {
+      client.getNewNews(getOld, urlListener, msgWindow);
+    };
+  }
 }
 
 NntpService.prototype.classID = Components.ID(

mailnews/news/src/moz.build

@@ -20,6 +20,7 @@ SOURCES += [
 
 EXTRA_JS_MODULES += [
     "NewsAutoCompleteSearch.jsm",
+    "NntpClient.jsm",
     "NntpModuleLoader.jsm",
     "NntpService.jsm",
 ]