Re: [Cppcms-users] C++DB + MySQL disconnect

[Jon F. <jon...@jf...>]

Done! Fixed! If anyone else cares.

- Jon


On 03/29/2021 01:22 PM, Jon Foster wrote:
> For anyone else who might care: This weekend I chased this back to the
> MySQL backend. The MySQL client library loses all "prepared" queries when
> the connection drops and they aren't made again when its auto-reconnected.
> The C++DB backend thinks the query is still there and tries to re-use it
> causing the "disconnect" error to act as if its being cached. I'll have to
> fix this.
>
> -Jon
>
>
> On 03/25/2021 10:43 AM, Jon Foster wrote:
>> This isn't specifically a C++CMS query. I'm using C++DB with C++CMS and
>> FLTK to query a MariaDB server. With other languages and tools I can tell
>> the client library to auto-reconnect and it does. From the C++DB docs I
>> should be able to append ";opt_reconnect=1" to the connection string and it
>> should auto-reconnect. But this has not been reliable, where in other tools
>> it is. My test FLTK app, which doesn't use a connection pool, will fail
>> after the idle timeout set in the server (1hr in this case) and *never*
>> reconnect. My C++CMS apps which use connection pooling kind of work but I
>> still get random 500s and logs telling me "MySQL went away". Fortunately it
>> seems to mostly re-connect if I hit another page and then come back to the
>> one that broke.
>>
>> But I *HATE* random fails in my projects. I'm not a "80% of the time it
>> works 100% of the time" kind of guy. So! Is there an easy fix for this? Am
>> I misinterpreting the docs and writing that option wrong? Or do I just need
>> to dig into the source and force that client option? I'm not even sure why
>> its an option. ;-) Anyhow I can't go live with a real C++CMS website and
>> have this happening.
>>
>> Versions:
>>
>> C++DB: 0.3.1
>> MariaDB: 10.0.38 & 10.2.25
>> G++: 4.9.2
>>
>> TIA,
>> Jon
>>
>>

-- 
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"Init Freedom", Yeah!

Jon Foster
JF Possibilities, Inc.
jo...@jf...