ch2rs

An auxiliary utility for generating Rust structures from ClickHouse DB schemas for the official clickhouse-rs crate.

Usage

cargo install ch2rs

The crate enables rustls-tls client feature by default, which allows to work with HTTPS URLs. If rustls-tls does not work in your use case, you can install the crate with native-tls instead:

cargo install ch2rs --features native-tls

Help

$ ch2rs --help

ch2rs 0.1.7

USAGE:
    ch2rs [FLAGS] [OPTIONS] <table>

FLAGS:
    -D               Generate `Deserialize` instances
    -h, --help       Prints help information
        --owned      Generate only owned types
    -S               Generate `Serialize` instances
    -V, --version    Prints version information

OPTIONS:
    -B <bytes>...              Add `#[serde(with = "serde_bytes")]` to the provided column
    -d <database>              A database where the table is placed in [default: default]
    -I <ignore>...             Ignore a specified column
    -O <overrides>...          Override the type of the provided column
    -p <password>
        --derive <trait>...    Add `#[derive(<trait>)]` to the generated types
    -T <types>...              Override the type, e.g. 'Decimal(18, 9)=fixnum::FixedPoint<i64, typenum::U9>'
    -U <url>                   ClickHouse server's URL [default: localhost:8123]
    --temporal <mode>          Temporal mapping: raw|time|chrono [default: raw]
    -u <user>

ARGS:
    <table>    The table's name

Temporal modes

• raw (default): uses primitive Rust types:

  • Date → u16, Date32 → i32
  • DateTime → u32, DateTime64(_) → i64
  • Time → i32, Time64(_) → i64

• time: uses the time crate types

  • Date/Date32: time::Date
  • DateTime/DateTime64: time::OffsetDateTime
  • Time/Time64: time::Duration
  • Requires in your project: time dependency and clickhouse feature time
    • clickhouse = { version = "…", features = ["time"] }

• chrono: uses the chrono crate types

  • Date/Date32: chrono::NaiveDate
  • DateTime/DateTime64: chrono::DateTime<chrono::Utc>
  • Time/Time64: chrono::Duration
  • Requires in your project: chrono dependency and clickhouse feature chrono
    • clickhouse = { version = "…", features = ["chrono"] }

Select mode via --temporal {raw|time|chrono}.

Examples

See snapshots.