implement more reliable check for whether a channel on the server is new

rpc.js

@@ -952,11 +952,38 @@ var upload_status = function (Env, publicKey, filesize, cb) {
     });
 };
 
+var isNewChannel = function (Env, channel, cb) {
+    if (!isValidId(channel)) { return void cb('INVALID_CHAN'); }
+    if (channel.length !== 32) { return void cb('INVALID_CHAN'); }
+
+    var count = 0;
+    var done = false;
+    Env.msgStore.getMessages(channel, function (msg) {
+        if (done) { return; }
+        var parsed;
+        try {
+            parsed = JSON.parse(msg);
+            if (parsed && typeof(parsed) === 'object') { count++; }
+            if (count >= 2) {
+                done = true;
+                cb(void 0, false); // it is not a new file
+            }
+        } catch (e) {
+            WARN('invalid message read from store', e);
+        }
+    }, function () {
+        if (done) { return; }
+        // no more messages...
+        cb(void 0, true);
+    });
+};
+
 var isUnauthenticatedCall = function (call) {
     return [
         'GET_FILE_SIZE',
         'GET_MULTIPLE_FILE_SIZE',
         'IS_CHANNEL_PINNED',
+        'IS_NEW_CHANNEL',
     ].indexOf(call) !== -1;
 };
 
@@ -1051,6 +1078,10 @@ RPC.create = function (config /*:typeof(ConfigType)*/, cb /*:(?Error, ?Function)
                 return void isChannelPinned(Env, msg[1], function (isPinned) {
                     respond(null, [null, isPinned, null]);
                 });
+            case 'IS_NEW_CHANNEL':
+                return void isNewChannel(Env, msg[1], function (e, isNew) {
+                    respond(null, [null, isNew, null]);
+                });
             default:
                 console.error("unsupported!");
                 return respond('UNSUPPORTED_RPC_CALL', msg);

www/common/cryptpad-common.js

@@ -252,6 +252,14 @@ define([
         });
     };
 
+    common.isNewChannel = function (href, cb) {
+        postMessage('IS_NEW_CHANNEL', {href: href}, function (obj) {
+            if (obj.error) { return void cb(obj.error); }
+            if (!obj) { return void cb('INVALID_RESPONSE'); }
+            cb(undefined, obj.isNew);
+        });
+    };
+
     // Store
 
 

www/common/outer/async-store.js

@@ -277,6 +277,21 @@ define([
         });
     };
 
+    Store.isNewChannel = function (data, cb) {
+        if (!store.anon_rpc) { return void cb({error: 'ANON_RPC_NOT_READY'}); }
+        var channelId = Hash.hrefToHexChannelId(data.href);
+        store.anon_rpc.send("IS_NEW_CHANNEL", channelId, function (e, response) {
+            if (e) { return void cb({error: e}); }
+            if (response && response.length && typeof(response[0]) === 'boolean') {
+                return void cb({
+                    isNew: response[0]
+                });
+            } else {
+                cb({error: 'INVALID_RESPONSE'});
+            }
+        });
+    };
+
     Store.getMultipleFileSize = function (data, cb) {
         if (!store.anon_rpc) { return void cb({error: 'ANON_RPC_NOT_READY'}); }
         if (!Array.isArray(data.files)) {

www/common/outer/store-rpc.js

@@ -160,8 +160,13 @@ define([
             case 'DRIVE_USEROBJECT': {
                 Store.userObjectCommand(data, cb); break;
             }
+
+            case 'IS_NEW_CHANNEL': {
+                Store.isNewChannel(data, cb); break;
+            }
             default: {
-                
+                console.error("UNHANDLED_STORE_RPC");
+
                 break;
             }
         }

www/common/sframe-common-outer.js

@@ -140,12 +140,10 @@ define([
         }).nThen(function (waitFor) {
             // Check if the pad exists on server
             if (!window.location.hash) { isNewFile = true; return; }
-            Cryptpad.getFileSize(window.location.href, waitFor(function (err, size) {
-                if (typeof(size) === 'number' && size >= 108) {
-                    isNewFile = false;
-                    return;
-                }
-                isNewFile = true;
+
+            Cryptpad.isNewChannel(window.location.href, waitFor(function (e, isNew) {
+                if (e) { return console.error(e); }
+                isNewFile = Boolean(isNew);
             }));
         }).nThen(function () {
             var readOnly = secret.keys && !secret.keys.editKeyStr;