qsv CSV sniffer

qsv-sniffer provides methods to infer CSV file metadata (delimiter choice, quote character, number of fields, field names, field data types, etc.). See the documentation for more details.

Its a detached fork of csv-sniffer with these additional capabilities, detecting:

• utf-8 encoding
• field names
• number of rows
• additional data types - Date and DateTime

ℹ️ NOTE: This fork is optimized to support qsv, and its development will be primarily dictated by qsv's requirements. Please continue to use csv-sniffer if you want a general-purpose CSV sniffer.

Setup

As a Command-line application

cargo install qsv-sniffer

This will install a binary named sniff.

As a Library

Add this to your Cargo.toml:

toml [dependencies] qsv-sniffer = "0.5"

and this to your crate root:

rust use qsv_sniffer;

Feature flags

• cli - to build the sniff binary
• runtime-dispatch-simd - enables detection of SIMD capabilities at runtime, which allows using the SSE2 and AVX2 code paths (only works on Intel and AMD architectures. Ignored on other architectures).
• generic-simd - enables architecture-agnostic SIMD capabilities, but only works with Rust nightly.

The SIMD features are mutually exclusive and increase sampling performance.

Example

This example shows how to write a simple command-line tool for discovering the metadata of a CSV file:

```norun use qsvsniffer;

use std::env;

fn main() { let args: Vec = env::args().collect(); if args.len() != 2 { eprintln!("Usage: {} ", args[0]); ::std::process::exit(1); }

// sniff the path provided by the first argument
match qsv_sniffer::Sniffer::new().sniff_path(&args[1]) {
    Ok(metadata) => {
        println!("{}", metadata);
    },
    Err(err) => {
        eprintln!("ERROR: {}", err);
    }
}

} ```

This example is provided as the primary binary for this crate. In the source directory, this can be run as:

ignore $ cargo run -- tests/data/library-visitors.csv