Add in-house connection pooling

[DarkWanderer]

No description provided.

[AlirezaEiji191379]

hi @DarkWanderer
do you need this feature? if you need it i want to implement it

[DarkWanderer]

Hi. Thanks for your suggestion - I will be interested in contributions

[smbecker]

Isn't this possible today with a single ClickHouseConnection and the existing connection pooling provided by HttpClient?

[DarkWanderer]

This is currently the default mode of operation.

The issue with this, unfortunately, is that .NET HTTP connection pooling is not well-compatible with ClickHouse session implementation. Specifically, ClickHouse sometimes - rarely - freaks out if there is still an open HTTP connection where a session has been used, and same session ID is then used from different HTTP connection. See #152

Current way to solve this issue is to create and own a HttpClientHandler with a single owned HTTP stream for each ClickHouseConnection - thus behaving more similarly to traditional SQL connectors. With that in mind, I wanted to complete the analogy and add "Pooling" parameters to connection string similar to how MySQL or Postgres libraries behave