Plans to provide a C Wrapper?

ClickHouse / clickhouse-cpp

C++ client library for ClickHouse

Apache License 2.0

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Plans to provide a C Wrapper? #356

Closed onguntoglu closed 9 months ago

onguntoglu commented 10 months ago

Are there any plans to provide a C wrapper over the existing C++ driver/client?

If not, what are my options apart from using the C++ library?

Enmk commented 10 months ago

Hi @onguntoglu, I am not aware of any such plans. May I ask you why exactly do you need such a library?

If not, what are my options apart from using the C++ library?

Maybe there is something developed by community, but that depends on your use-case.

onguntoglu commented 10 months ago

Hi @Enmk, I am currently building a real-time application in C which receives 50 MSamples/s (in batches of 1M samples every 20ms) from a testbench and processes the data (filtering, downsampling and some transformations), and I need a system to record all this data and query it for further analysis at a later time

All the other database solutions did not meet the hard real-time requirement, I read/heard good things about Clickhouse and played with the web-interface a little bit and thought I'd try it out. There are a lot of parts to the application which are entirely written in C, so pulling in C++ is kind of painful (for me at least) and admittedly C++ is not my forte.

Enmk commented 10 months ago

Sorry @onguntoglu, but I am not aware of no plans for C-style library. Perhaps you can take an inspiration from how other c-projects are interfacing with clickhouse:

https://github.com/Percona-Lab/clickhousedb_fdw/blob/master/src/clickhousedb_binary.c -- uses this library.
https://github.com/eait-itig/flow-collector/tree/main -- submits data via an HTTP POST requests, serializing values to string
https://github.com/openbsod/nginx2clickhouse/tree/master -- submits data via HTTP POST

onguntoglu commented 9 months ago

Hi, I have found a workaround: I wrote a separate application in C++ which receives the data over ZeroMQ and inserted the data using the C++ library. It is working okay as far as I can observe, so I am no longer looking for a C wrapper. Thank you for the fast response and the links!

moaazassali commented 4 months ago

If you would still prefer using a C wrapper (or for anyone in the future checking this), I made one here https://github.com/moaazassali/clickhouse-cpp-c-bridge

It covers almost everything from clickhouse-cpp with full testing. The few missing features are minor like query progress and server log callbacks, but they will be added shortly.