From b3cc8da315c0017ff78ef36136390e020b30bb26 Mon Sep 17 00:00:00 2001
From: ansuz <ansuz@transitiontech.ca>
Date: Fri, 10 Mar 2017 18:03:52 +0100
Subject: [PATCH] implement basic clientside RPC infrastructure

and provide a basic example for testing it
---
 www/common/rpc.js           | 88 ++++++++++++++++++++++++++++++-------
 www/examples/rpc/index.html | 13 ++++++
 www/examples/rpc/inner.html |  8 ++++
 www/examples/rpc/main.js    | 35 +++++++++++++++
 4 files changed, 129 insertions(+), 15 deletions(-)
 create mode 100644 www/examples/rpc/index.html
 create mode 100644 www/examples/rpc/inner.html
 create mode 100644 www/examples/rpc/main.js

diff --git a/www/common/rpc.js b/www/common/rpc.js
index 3d15843cc..8cb7c6f8a 100644
--- a/www/common/rpc.js
+++ b/www/common/rpc.js
@@ -3,26 +3,73 @@ define([
 
     '/bower_components/tweetnacl/nacl-fast.min.js',
 ], function (Encode) {
+    var MAX_LAG_BEFORE_TIMEOUT = 30000;
 
-    var getHistoryKeeperName = function (network) {
-        var wc = network.webChannels[0];
-        if (!wc) {
-            throw new Error("ERROR: no joined webchannels so we can't get the history keeper name");
-        }
-        if (!wc.history_keeper) { throw new Error("ERROR: no history keeper"); }
-        return wc.history_keeper;
+    var uid = function () {
+        return Number(Math.floor(Math.random() * Number.MAX_SAFE_INTEGER))
+            .toString(32).replace(/\./g, '');
     };
 
-    var sendMsg = function (ctx, cb) {
-        var hkn = getHistoryKeeperName(ctx.network);
+    /*
+types of messages:
+    pin -> hash
+    unpin -> hash
+    getHash -> hash
+    getTotalSize -> bytes
+    getFileSize -> bytes
+
+    */
+
+/*  RPC communicates only with the history keeper
+    messages have the format:
+        [TYPE, txid, msg]
+*/
+    var sendMsg = function (ctx, type, msg, cb) {
+        var network = ctx.network;
+        var hkn = network.historyKeeper;
+        var txid = uid();
+
+        ctx.pending[txid] = cb;
+
+        return network.sendto(hkn, JSON.stringify([txid, type, msg]));
     };
 
+    var parse = function (msg) {
+        try {
+            return JSON.parse(msg);
+        } catch (e) {
+            return null;
+        }
+    };
+
+/*  Returning messages have the format:
+    [txid, {}]
+*/
     var onMsg = function (ctx, msg) {
-        console.log(msg);
+        var parsed = parse(msg);
+
+        if (!parsed) {
+            // TODO handle error
+            console.log(msg);
+            return;
+        }
+
+        var txid = parsed[0];
+        var pending = ctx.pending[txid];
+        var response = parsed.slice(1);
+
+        if (typeof(pending) === 'function') {
+            if (response[0] === 'ERROR') {
+                return void pending(response[1]);
+            }
+            pending(void 0, response);
+        } else {
+            console.log("No callback provided");
+        }
     };
 
     var cookie = function (ctx, cb) {
-        // TODO
+        // TODO txid
     };
 
     var signMsg = function (msg, secKey) {
@@ -31,16 +78,27 @@ define([
 
     var create = function (network, edPrivateKey) {
         if (!/[0-9a-f]{64}/.test(edPrivateKey)) {
-            throw new Error("private signing key is not valid");
+            //throw new Error("private signing key is not valid");
         }
         var ctx = {
-            privateKey: Encode.hexToUint8Array(edPrivateKey),
+            //privateKey: Encode.hexToUint8Array(edPrivateKey),
             seq: new Date().getTime(),
-            network: network
+            network: network,
+            timeouts: {}, // timeouts
+            pending: {}, // callbacks
+        };
+
+        var pin = function (channel, cb) { };
+
+        var send = function (type, msg, cb) {
+            return sendMsg(ctx, type, msg, cb);
         };
-        network.on('message', function (msg) { onMsg(ctx, msg); });
+        network.on('message', function (msg, sender) {
+            onMsg(ctx, msg);
+        });
         return {
             cookie: function (cb) { cookie(ctx, cb); },
+            send: send,
         };
     };
 
diff --git a/www/examples/rpc/index.html b/www/examples/rpc/index.html
new file mode 100644
index 000000000..e17a68143
--- /dev/null
+++ b/www/examples/rpc/index.html
@@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html class="cp slide">
+<head>
+    <title>CryptPad</title>
+    <meta content="text/html; charset=utf-8" http-equiv="content-type"/>
+    <script data-bootload="main.js" data-main="/common/boot.js" src="/bower_components/requirejs/require.js"></script>
+</head>
+<body>
+    <div id="iframe-container">
+        <iframe id="pad-iframe"></iframe><script src="/common/noscriptfix.js"></script>
+    </div>
+</body>
+</html>
diff --git a/www/examples/rpc/inner.html b/www/examples/rpc/inner.html
new file mode 100644
index 000000000..9680685b7
--- /dev/null
+++ b/www/examples/rpc/inner.html
@@ -0,0 +1,8 @@
+<!DOCTYPE html>
+<html>
+<head>
+    <meta content="text/html; charset=utf-8" http-equiv="content-type"/>
+    <meta name="viewport" content="width=device-width, initial-scale=1.0"/>
+</head>
+<body>
+<h1>PEWPEW
diff --git a/www/examples/rpc/main.js b/www/examples/rpc/main.js
new file mode 100644
index 000000000..528290d66
--- /dev/null
+++ b/www/examples/rpc/main.js
@@ -0,0 +1,35 @@
+require.config({ paths: { 'json.sortify': '/bower_components/json.sortify/dist/JSON.sortify' } });
+define([
+    '/common/cryptpad-common.js',
+    '/common/rpc.js',
+    '/bower_components/jquery/dist/jquery.min.js',
+], function (Cryptpad, RPC) {
+    var $ = window.jQuery;
+    var APP = window.APP = {
+        Cryptpad: Cryptpad,
+    };
+
+    $(function () {
+        Cryptpad.ready(function (err, env) {
+            var network = Cryptpad.getNetwork();
+            var rpc = RPC.create(network); // TODO signing key
+
+            var payload = {
+                a: Math.floor(Math.random() * 1000),
+                b: 7,
+            };
+
+            // console.log(payload);
+            rpc.send('ECHO', payload, function (e, msg) {
+                if (e) { return void console.error(e); }
+                console.log(msg);
+            });
+
+            // test a non-existent RPC call
+            rpc.send('PEWPEW', ['pew'], function (e, msg) {
+                if (e) { return void console.error(e); }
+                console.log(msg);
+            });
+        });
+    });
+});