Fix sync connection serial in the event of a failed upgrade #445
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paddybyers
reviewed
Jan 3, 2018
| @@ -387,14 +387,14 @@ var ConnectionManager = (function() { | |||
| * be a sync with the new connectionSerial (which will be -1). (And it | |||
| * needs to be set in the library, which is done by activateTransport). */ | |||
| var connectionReset = connectionId !== self.connectionId, | |||
| newConnectionSerial = connectionReset ? connectionSerial : self.connectionSerial; | |||
| syncConnectionSerial = connectionReset ? preUpgradeConnectionSerial : self.connectionSerial; | |||
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scheduleTransportActivation() is passed the connectionSerial from the CONNECTED message when the upgrade transport connects. So how is this the preUpgradeConnectionSerial ?
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In the sense that the sync as the atomic moment of the actual 'upgrade', so preUpgradeConnectionSerial is the serial of the upgrade transport before that (likely -1). Can change to preSyncConnectionSerial if you think that's clearer
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Merged as 7a63754 |
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And rename various connectionSerial variables for clarity
(context from slack: "when it was first written, that code was correct, because at the time, we activated the new transport before syncing, so the first newConnectionSerial was passed to activeTransport and served its purpose. Later on in an unrelated change (https://github.com/ably/realtime/issues/522), to address a race condition, we switched the order of those and started syncing first, but I clearly failed to notice that the logic for when the upgrade failed needed to be updated too")